Mambas invade Hot Rod Hobbies

[GSMnow]

Wow! I don't think I can take all the credit, but I think I have had some influence. Tonight there were at least 4 Mamba Max powered 4WD buggies at the race. Too bad the Dark Impact had too much of an impact early on and lost the left front suspension. That left 2 Losi XXX-4's and a Tamiya Durga in the Mod class main running MM5700 systems. I was on my light 3000 LiPo's in my XXX-4, the Durga had a Reedy 5000 LiPo in it, and the other XXX-4 was using my best old EP4200 pack, which proved to be up to the task power wise. He out qualified me on my own battery. The top 5 qualifiers all had 12 laps. The Durga ran quite well, and when he gets better rubber and good shocks, it will be running strong, he had all the speed, in fact in a great side by side, I pulled him onto the straight, got 5-6 feet on him, but he closed it up half way down, and got 5 feet on me by the sweeper. But the tires and shocks got the best of him and I got the inside line to make the pass into the infield. The T.Q. B44 got away clean at the start and never looked back, he was beating me by a second a lap on average, so I still have some work to do. Not sure what he was running for power, I am guessing a Novak 5.5 or so. He just out handled me in the infield. Power could not over come that. I was gaining a good second a lap on the second place B44 for most of the race, and he finally made a mistake with just 50 seconds to go, I drove under him while the marshall went to get him, and he could not catch me back. So I put the XXX-4 MM5700 in second place. I put a lap on the other two Mamba Max's, the XXX-4 had a ball cup pop off, but got back on track and finished just 1 lap behind, not bad. The Durga can put down power, even with the wrong tires. He just barely missed 11 laps. 3rd or 4th with 11 laps was the first 19 turn buggy. That is some good driving. The layout is getting beat up, and a 2WD buggy is a serious handful through the infield now. Even my XXX-4 was having trouble gettnig kicked around between the S's and the big table top. The step down and the turn before the "W" is no better either. I think that is where the Durga's plastic shocks really hurt too.

Well Patrick... when your Mamba Max 5700 gets bolted into a 4WD, it really can stretch it's legs. We all got the motors up around 175F in the main. My ESC with a 25 mm fan stayed under 140F, but the other two were closer to 160F after the 5 minute race. My 20C 3000 LiPo's are starting to show they just are not quite tough enough. They bever gave any trouble in my 2WD truck, but with the 4WD traction, 60 amps constant is just not enough. Qual 2 took just under 1500 mAh to re-charge, and I did 2 laps before the start, and a lap after the finish. So my average current is certainly under 20 amps, but the peaks must be insane. The battery pack hit 160F again, in just 6 minutes.

I think one of the B44's also had a SideWinder in it, and there very well could have been another Mamba I didn't see. For many months, I was the only Mamba Max racing here. Many said they were just too course to race, you need sensors. Oh well.... Watching my 4WD buggy take a T.Q. and a second place a few weeks back, and letting a few others drive it, seems to be showing that it is plenty smooth. Many feel the trigger is nicer than the orange ones. Today I took a second in my qualifier, but the other heats had a few faster times, so I was stuck 5th on the grid of 11. The smoothness allowed me to drive in traffic up to second. I had quite a few fun side by side situations and was able to pedal it to hold a line. The ESC is better than my reactions and trigger control. And talk about consistent.. 9 of my 12 laps were from 26 to 28 seconds. Then there is the 12 second half lap at the start, and a 30 and 29 when I was looking for a clean pass. I even had four low 28's in a row. Not as good as the 25's and 26's I did a couple weeks ago, but a lot of that was the track condition.

Too bad the Mamba Max motors will never be ROAR legal, they sure make a ton of (nice smooth) power.

[rccardude04]

I really don't understand why ROAR won't legalize them. They're all over the place, and cheap. Isn't the point of ROAR to make it fair and inexpensive for all of us? I don't see any advantage to the CM36 motors over a Vortex or something that's actually legal.
I think it's time for ROAR to do what they're supposed to and listen to their members as well as just simply doing what makes sense... But Castle doesn't pay them the big bucks like Trinity or Orion...

-Eric

[GSMnow]

Just take a look at the members of the ROAR board...
They want to keep it fair, but they also want everyone to have to buy from a company that has a person on the board. If Novak went and designed a coreless motor like the CM36's, I am sure they could have the rules altered so they could run it. But even then, Castle just won't bother with the politics to submit their's or do the other silly stuff like lable the A-B-C, engrave their logo in the endbell, and have it easilly re-buildable, let alone pay the fees and submit test motors. So they will never be legal. Castle sells probbaly 4 times as many motors as Novak, so they really don't care about the racer market, it is just so small vs the basher market that they own.

The Feigao sensored motors are not legal, but at least two companies are buying them, putting their name on it, and they submitted them to ROAR and those are legal, but the same motor straight from Feigoa is not legal. Go figure.

[nicholcgn]

Yea go figure. They did not take the time and effort to get their motor approved. And everyone complaining about things like this would complain when some new motor approved by default started winning. Don't blame ROAR. They have their rules and anyone is able to play within the rules.
Oh yea and anyone is able to help change the rules. But just because you have a product does not mean they should change the rules. If they were to do that then we would just not have any rules.


Trust me if they approved everything because it is popular then you will end up having to buy new stuff all the time. XXX is now better. Oh it is popular we need to approve it. Here is my checkbook.

If you dont like it vote for changes and run for office.

ROAR approved lipos. So they do listen.

I am glad to see people running the Castle stuff at the club level. If that continues you will see things slowly change. Club level racing should have no problems with most Roar rules being stretched to fit their clients. And if there are enough of you then things can change.

[lennythe]

Sorry but I am siding with GSMnow on this one. I admit I am not overly impressed with all of roar's rules. Just like the real government, the people governing are more interested in making rules instead of thinkin about what the rules will do. I am not trying to imply that all their rules are bad but if their rules talk about a sensor and you build sensorless motors, you are throwing good money after bad trying to submit it for approval in my opinion. I do race a MM at the club level and love passing them legal sensored motors!

[GSMnow]

I totally understand the reason for stable rules. You need to keep the playing field level for at least a year at a time or you will certianly drive people away. When Castle designed the CM36 motors, there were no ROAR rules for brushless. They just built a motor to make power and fit in place of a brushed 540. The way the rules ended up were so different than what Castle built, they didn't even care to try and submit it. And I have asked Patrick of Castle and he said out right, they won't change thier motor to fit the rules because it would lose a lot of power and cost more to make, so why do it. Hacker was in the same boat, but for some reason, they decided to jump onto the ROAR legal sensored motor design, that really surprized me.

I can't blame ROAR or Castle for the current situation. Castle can't keep up with the demand now, so they certainly don't have the time to develop a lower performance motor. And if ROAR jumped from the current motor design to coreless in one step, there would be a huge shift in performance. The motors without lamination stacks can cram in much more wire which greatly improves the ability to handle current for a given KV. This is how a Mamba Max with just 5700 KV can make as much power as the sensored 9,000 KV motors. If in the future, another company jumps through the ROAR hoops to make a coreless motor legal, then Maybe (I doubt it) Castle could submit theirs.

The rules do have a slot for sensorless operation, so I will be testing a "legal" motor on my Mamba Max ESC. I have not decided yet, but I am leaning to the 13.5 for super stock in my truck on a maybe a SideWinder. This should be legal, but there is some mention of being sensored for the spec classes?? If so, then the Speed Passion GT becomes the ESC of choice. I think it is the only sensored unit to run with dynamic timing.

I am also thinking of a 6.5 in my 4WD on the Mamba Max. I know it won't be as fun as the MM5700, but it will be legal. How many fans can I stuff into a XXX-4 to keep it from melting?

I am now looking into stronger LiPo's. I am certainly over working my little 3000's in the XXX-4. I hate pulling them out hot and feeling the shrink wrap bulged in the middle. So far they still run the same and have not lost capacity, but it is scary. I would love a pair of legal packs, but they are so much more expensive. The Trinity has the built in cutoff system, but I think it was causing trouble. The guy running one had it shut down before the end of the race. I only used 1500 mAh out of my 3000, and his was a 4800. He ran the main on a Reedy 5000 with no problems.

[rccardude04]

The trinity pack is crap. I've heard it from a few sources. They've used cheap cells like they used a cheap motor. They're using their name to carry them afloat the top right now instead of developing new stuff and leading the way in quality and performance.

I still like my TrakPower 4900 gold-cased batteries. You have to use their proprietary balancer (or something similar) but it works. And it works well.

-Eric

[ElectricThunder]

The Trinity pack is not up to higher power tasks. I've "retired" mine to my TT-01 running an XBR/SS5800 w/sintered rotor setup, and it fairs quite well in there. It's a good match to that setup; especially with the little built in cutoff doohickey. I definitely need some better lipos for my Rustler now.

It just cannot handle my Medusa/Mamba setup in my Rustler though. Enerland cells are supposed to be the ones to beat now (which Trak Power uses). Kong Power also uses some interesting cells as well, and may be interesting to check out (take abuse better like over charging and over discharging compared to your typical lipo cells).

I'm looking at a 2s Neu Energy pack myself (again...Enerland cells...:D).

[lennythe]

At the race I was just at, they went by roar rules and mod could be sensorless, but stock had to be the 17.5 with the sensor wire plugged in making the max controller illegal in that particular class but they did open it up for mod whick I was happy about.

[ElectricThunder]

Sensorless motors aren't necessarily an illegal technology. It's just that no one has made a sensorless ROAR legal design yet to my knowledge (probably because the ROAR design is a pain in the butt to eliminate cogging from a dead start on a sensorless ESC in the first place). It's probably far easier to design a ROAR legal motor that is sensored for easy driveability than a sensorless model (because not even the mamba's new firmware drives sensored motors perfectly from a dead stop; once you get going, it's great though).

[GSMnow]

I re-read the ROAR rules again, to verify. It does not say anything about the ESC. You can run any brand at all, it does not say it must use the sensors, in fact there is no mention of the ESC. It does state the motor must be sensored for stock and superstock. But again, it does not say they must be in use. It is certainly a grey area. I know I can cut a slot in the side of my Mamba Max case and install a JST connector. I could even wire up the grnd and 5 volt pins. This way, the cable will be plugged in.

What I would really like to see is a coreless motor with sensors to see how a Novak ESC can run a motor like the CM36. The actuall design of the motor has nothing to do if it has snsors in it or not. The Neu motors have a lamination stack in them, but no sensors. But they are 4 pole rotors, so not legal. They are also a bit larger to fit the amount of wire needed, and with 4 poles, they get good low KV's even with 2 turns, so they have very low internal resistance.

I know enough electronics to know that sensored will always work smooth at startup and very low rpm operation. But once you are turning fast enough to get good back EMF off the windings, there is no longer any advantage to carrying the sensors and the wiring harness back to the ESC. Then there is the intelligence f the controller. Up until very recently, most sensored controllers were not intelligent. They just used the signal from the sensors to switch the current to the next winding. This is why you time the motors by adjusting the sensor position just like a brush motor. This forced fixed timing has big limitations. The Speed Passion GT is the first one I have seen that will run dynamic timing advance. All sensorless ESC's must have enough intelligence to calculate when to switch the current. This requires a fairly fast microcontroller to even run at all. So the ESC's that can run sensored or sensorless should all be able to do dynamic timing, but most don't. With the fixed timing optimised, the sensored systems should still make the same power as a sensorless with the same motor. It all comes down to switching speed and resistive losses. The sensorless though, can back off the timing at lower speed to be more efficient and make more torque for a given current draw, or draw less current for a given acceleration.

Now there is a different reason to choose between the technologies.
We actually do have a point where we have more power than we can use. Having a motor with a little less low rpm torque may be easier to drive. Everyone was on a quest for max power, but now the ease of control is getting more important. Novak came up with the L series of motors just to make them have less torque and be a bit more forgiving if you grab too much trigger. I think this is something that proper software could do much more efficiently.

Again, sensored vs sensorless is not really the debate. Once turning, they should be the same, given the same intelligence in the ESC. Either one could benefit from rpm based current limiting. This is still not traction control, but if you could say.. I want 30 amps from a stop to 2000 rpm, then ramp to 50 amps to 12000, and to 100 amps to 30,000 and beyond... You get the idea.

Original topic
Keep those Mambas coming. It is alot of fun seeing the "undriveable" coarse running sensorless stuff beating up on the team drivers.

[hypercar]

Wow, very interesting read, GSMnow! I wish I could have been there, I really like that the 4wd class is growing. I haven't been to Hot Rod on a Saturday night, yet, but on Tuesdays there were always at least a couple. I'd really like to see some of those Tamiya cars running the track. :)
I'm working a ton right now, and for the next few weeks, so probably no racing for me anytime soon. I was running an LRP Bullet Reverse ESC and a Banzai 12 turn brushed, but I'm finally pretty fed up with that speed control, so I bought a Novak 6.5 setup. I don't have it in yet. It should be about the same speed, but ALOT smoother. And I'm sure the Novak ESC will be tons better than the LRP auto-setup thing.
Still looking forward to running into you up there!

sean

[lennythe]

I read them and agree it is a grey area by reading the rules and I should print out that page but I could only go by what the "officials" said at the race I was at. It is a 5 date race series here in Michigan. I never ran a series before and I ran mod truck with the 4600kv. All I can say is wow, The track I normally go to just isn't big enough to actually see what the 4600 can do. I am near speakless after driving the thing on a big track. The weight of the truck was over 4 pounds when they teched it so I guess I was getting plenty of traction with the extra weight cause the 4600 had no problems pulling the front end in the straight . I didn't place as well as I would have hoped but I left with a huge smile !

[ElectricThunder]

I re-read the ROAR rules again, to verify. It does not say anything about the ESC. You can run any brand at all, it does not say it must use the sensors, in fact there is no mention of the ESC. It does state the motor must be sensored for stock and superstock. But again, it does not say they must be in use. It is certainly a grey area. I know I can cut a slot in the side of my Mamba Max case and install a JST connector. I could even wire up the grnd and 5 volt pins. This way, the cable will be plugged in.

What I would really like to see is a coreless motor with sensors to see how a Novak ESC can run a motor like the CM36. The actuall design of the motor has nothing to do if it has snsors in it or not. The Neu motors have a lamination stack in them, but no sensors. But they are 4 pole rotors, so not legal. They are also a bit larger to fit the amount of wire needed, and with 4 poles, they get good low KV's even with 2 turns, so they have very low internal resistance.

I know enough electronics to know that sensored will always work smooth at startup and very low rpm operation. But once you are turning fast enough to get good back EMF off the windings, there is no longer any advantage to carrying the sensors and the wiring harness back to the ESC. Then there is the intelligence f the controller. Up until very recently, most sensored controllers were not intelligent. They just used the signal from the sensors to switch the current to the next winding. This is why you time the motors by adjusting the sensor position just like a brush motor. This forced fixed timing has big limitations. The Speed Passion GT is the first one I have seen that will run dynamic timing advance. All sensorless ESC's must have enough intelligence to calculate when to switch the current. This requires a fairly fast microcontroller to even run at all. So the ESC's that can run sensored or sensorless should all be able to do dynamic timing, but most don't. With the fixed timing optimised, the sensored systems should still make the same power as a sensorless with the same motor. It all comes down to switching speed and resistive losses. The sensorless though, can back off the timing at lower speed to be more efficient and make more torque for a given current draw, or draw less current for a given acceleration.

Now there is a different reason to choose between the technologies.
We actually do have a point where we have more power than we can use. Having a motor with a little less low rpm torque may be easier to drive. Everyone was on a quest for max power, but now the ease of control is getting more important. Novak came up with the L series of motors just to make them have less torque and be a bit more forgiving if you grab too much trigger. I think this is something that proper software could do much more efficiently.

Again, sensored vs sensorless is not really the debate. Once turning, they should be the same, given the same intelligence in the ESC. Either one could benefit from rpm based current limiting. This is still not traction control, but if you could say.. I want 30 amps from a stop to 2000 rpm, then ramp to 50 amps to 12000, and to 100 amps to 30,000 and beyond... You get the idea.

Original topic
Keep those Mambas coming. It is alot of fun seeing the "undriveable" coarse running sensorless stuff beating up on the team drivers.


Interesting point GSM. I remember Patrick talking about the Mamba Max, and how it has the dynamic timing built into it, so automatically it selects an optimum timing range and varies it for the motor being used (and then you can tweak this in the castle link if you want even further). I really like the Speed Passion ESC, but the price is ridiculous compared to the same thing being offered by Venom and under HobbyWing (the people who make the ESC).

I would love to test out that GT ESC though and compare it to my Novak ESC. I think Shawn Palmer, who now works for Schumacher, said he noticed a good improvement in motor performance from that dynamic timing. Really cool stuff.:eek:

I'm pretty happy with my Mamba/Medusa setup though (pretty dang smooth too!).

[lennythe]

I know a guy with the new speed passion and the new losi and he prefers the losi which has a lot of the same programability of the max. He didn't really say why he liked the other one better .

[GSMnow]

I forgot to mention, I guess someone has a few old Mamba Max's on the shelves still. One of the guys at the race Sat. had 1.09 firmware in his new system. And he thought it was great. I updated it to 1.17 for him and dialed in a few settings and he was really amazed at the difference. The change dropped his lap time over a second a lap on average, and his fastest lap was more like 2 seconds faster. For some odd reason, he could not get his computer to link. So he did the whole open practice time on default settings, even reverse enabled and no LiPo cutoff. His and the XXX-4's Mamba Max still both had the crappy bullet connectors too, and the ones on the XXX-4 crapped out in the first qualifier. It was stuttering off the corners and the motor got very hot. He direct soldered it during the break and it helped a ton. All stuttering was gone. The motor still got a bit hotter than moine, but it turns out he is geared a bit higher. He is running 19 to 92, I am running 16 to 94. That is a pretty big difference. Torque to the wheels though, ended up pretty close, as both our cars are blazing the slipper clutch at will. I don't know which firmware is in his, but since he has Castle Link working on his computer, it probably told him to update. Withthe solder job and my EP4200 pack on board, it sure took off smooth and had plenty of grunt anywhere on track. Too bad he had that ball cup pop off on lap one. Good thing he had a friend pop it back on too. His lap times were pretty close to mine. It would have been a good race.

On the other thoughts... There are many little things that can make someone prefer one ESC over another. Just the throttle curve can make an otherwse great system "feel" lousy. The Mamba Max let's you dial that in however you want, but just plain linear feels really good to me. The Novak I drove jumped like mad in the first 1/3 of the trigger, but the last third really didn't do anything. With equivolent motors, the Novak GTB should be really close to the same power as a Mamba Max. They are right on spec for internal resistance, and with the timing dialed in, they should make close to the same peak power. The scary power of a Mamba Max system comes from the illegal motor design. I am very happy they let us run them for the club races. But I also will agree, there are many cases where it is just too much power. In my XXX-T stadium truck, it was very hard to drive it to the limit. A Novak 7.5L would be much nicer to control, and probably turn faster laps. Sure, it is 1/2 the max wattage, but when you can't use more than 1/2 the power 90% of the time, whats the point? How much time is 5 feet at 40 mph? It works out to 0.09 seconds. That is what I can pull on the Novak 6.5R powered 4WD on the long straight, the only place I could go full throttle with the Mamba Max 5700. Maximum power does not always win the race. They guy who beat me last Sat. did it by gaining nearly 1.0 second per lap, every lap, in the tight infield. He is a better driver and his car was handling the beat up parts of the track better. The 5 feet I gained on the straight was no match for that.

[lennythe]

Yet again I agree with you. Even after going to the 4600kv , I still had way more power than needed. In an onroad 4wd car I think the castle motors would be insanely fast and could use the power. On my regular track on dusty clay, he with the most traction usually does pretty good and when all the truck does is light them up, hard to improve. That being said, sometimes it is just fun to blow past someone on the straight and to hear others on the drivers stand say "damn !" . A friend of mine ran an older novak 5800ss with a new rotor in it on his MM and I think he took the main that day. A nice 7.5L motor or something, I would like high top end and a little less torque and I don't know which motor out there would be the best for that. So I am open to suggestions as to what others have tried. I have only run the 6900 and 4600 on my MM and feel I am not using it to its full potential with all the motors out there to choose from. Sensored or not, I like the esc enough to run whatever kind of motor on it.

[GSMnow]

In a 2WD stadium truck, I think the hot motor will be something like a 7.5L or a 6.5L if you need a little more top end. The L motors intentionally have more internal resistance to soften the torque kick to make them easier to drive.
The 7.5L is rated at 5400 KV and 250 watts
The 6.5L is rated at 5900 KV and 315 watts

The MM5700 is duh.. 5700KV and the speed was about perfect.
but the kicker is, 500+ watts, TOO MUCH TORQUE

Assuming an average 6 cell NiMh you get 6 volts at 50 amps, or 300 watts.
A good 2S LiPo could top 80 amps at 7 volts, or 560 watts. The performance of the Mamba Max varied greatly with how good your batteries are, the 7.5L will run about the same with either.

I have not personally tried one yet, but it sure seems like the hot ticket. Withthe MM5700 in my truck, I was ALWAYS able to cut my best laps, right before the battery dumped, when it was going into low volt cut and limiting current to under 50 amps, less than 300 watts.

[lennythe]

I will say that the truck was easier to drive with my good 4200's in it, switching to lipo's was just rediculous what the difference was.

[GSMnow]

Yup! When I went to LiPo in the truck, I had to add over a half pound of dead weight to help the traction. It was totally undriveable without the ballast. It sure was faster down the straight on LiPo though. I am pretty sure my lap times ended up better on LiPo, but I was not able to do a good A-B compare. With the LVC set to 6.2 for the LiPo's it would not drive on the NiMh's.

[crazyjr]

I really don't understand why ROAR won't legalize them. They're all over the place, and cheap. Isn't the point of ROAR to make it fair and inexpensive for all of us? I don't see any advantage to the CM36 motors over a Vortex or something that's actually legal.
I think it's time for ROAR to do what they're supposed to and listen to their members as well as just simply doing what makes sense... But Castle doesn't pay them the big bucks like Trinity or Orion...

-Eric

The only things that kill the castle motor for rules is that 1. they are not rebuildable, 2. they are delta wind over wye and 3. the castle logo is not stamped or machined into the endbell. otherwise they could be with submission. However that said, How can the hacker C40 motors be legal? last i knew they were delta, so are some of the trinity's. If castle is smart, When they re-do the cm36 motors to a Neu type as is said in some forums, they will do it 2 pole and wye winds for legality. Then we can make them cry legaly. at least offer legal motors with the lineup

[ElectricThunder]

crazyjr, the rotor size of the mamba motors I think also makes them illegal (I think they're 17x17, which means it exceeds the 14mm diameter rotor rule).

They're redoing the CMS36 motors in Neu style? Saweet. Hopefully they still cost the same after that redesign (I read that rotor RPM will be good for up to 100k!)...:D

[PatrickdelC]

The only things that kill the castle motor for rules is that 1. they are not rebuildable, 2. they are delta wind over wye and 3. the castle logo is not stamped or machined into the endbell. otherwise they could be with submission. However that said, How can the hacker C40 motors be legal? last i knew they were delta, so are some of the trinity's. If castle is smart, When they re-do the cm36 motors to a Neu type as is said in some forums, they will do it 2 pole and wye winds for legality. Then we can make them cry legaly. at least offer legal motors with the lineup

No, there's a LOT more to the rules than just rebuildable, 2 pole, and Wye wind.

They must be slotted, salient pole wound motors, and have the same inductance as the Novak motors AND the exact same rotor size as the Novak motors...

Patrick

[ElectricThunder]

Patrick, I will say this:

Eff ROAR.:)

Do what you do best; put out some kickin' brushless stuff.:D

[GSMnow]

Reading the ROAR rules for the modified brushless, they did open it up a bit, but it is still very grey. Not thatthe CM36 will ever be legal there, but they did open the door a little.

The Hacker motor that is legal now, is not a C40, it is the E40 line, it is all new and built to the ROAR specs. And you will really like this part, they are made in China. The machining quality looks first rate, and they are a nce 2 tone black and purplr anodized. The sensor cable comes right out of the back, not removable like some others. I held the 13.5 in my hand, it has no vent holes. It really looks like the Novak motors, and might actually be the Feigao sensored re-badged, don't know for sure. It is odd to turn the shaft of a brushless motor and feeling the magnet pull to the 6 positions like a brush motor, with the brushes removed. The guy who had it should be running it in 19 turn this Sat. I am curious to see how it compares to the Novaks. He will be using a GTB ESC on it, so it will be sensored operation. A couple days ago he was testing his Novak ROAR stock 17.5 setup. All torque, no rpm. In a T4 truck, he had to gear it 28 to 78 and his straight speed was still down a bit from other stockers but it still had gobs of acceleration, spining the tires at will, and his motor temps never hit 100F. Odd for Santa Clarita though, it was only 70F ambient. When I left he was going to try a 30 and 32 tooth pinoins as well as cranking up the timing a bit on the sensors. The 17.5 is rated at 2200 KV. I ran 18:87 in my truck on a 5700. That puts my spur gear turning at about 8200 and his is only turning about 5500, That explains why he is still slow. Sure, mine is mod class, but he should still be closer than that down the straight. Mine works out to 38 mph, his is only 25. I gues that explains the cool motor temps. He will need about a 34 tooth to hit 30 mph. I wonder how much rpm he can gain with the timing??

[winning edge designs]

This is an interesting thread....

I am in the market for my first Brushless setup(Not counting the early LRP experience I am trying to forget, from a couple years ago).

Although I have been racing Modified for years(About 20+) my son will also race it and has a couple years experience...it looks like the LRP Competition, or Novak is the best all around, the Mamba for a little bit crazier power, since we'll be running Li-po's.

I'm thinking LRP/Novak 9-10.5 or so, or Mamba 5700?

Let me know what you experienced brushless guys would buy right now if you get another set up?


Thanks
...Jim
W.E.D.

[ElectricThunder]

If I were to get another setup, I would definitely get a mamba max again. However, I do have a Novak SS5800 with a sintered rotor running on an XBR/SS ESC hybrid thing.

I love the Novak setup; it's definitely tame enough for racing, but still has plenty of power to not get bored when I bash around. Plus I get some good runtimes out of it on 2s lipo too. The setup runs pretty cool too in a TT-01.

If you're going to stick with solely racing, then the Novaks/LRPs (I don't like LRP; I've had two of their ESCs poop out on me vs. my Novaks) are probably a good bet. They're still fun systems to bash around with if you get the itch to do something like that and can't race at that point in time.

The mamba has the adjustability though, which I LOVE so much.

Ya know... Perhaps you should wait for the Venom brushless setups to come out? They run sensored (via a sensor port) or sensorless motors, have a little program box, and for $230 (a tad more than the cost of mamba max setup), you get the ESC, motor, and the program box thingy.

Best of both worlds IMO.

[GSMnow]

The choice between a sensored or sensorless system is not a simple black and white choice. I will leave the motor out of it for now and just talk about the difference in how a sensored system feels to drive vs a sensorless.

A sensored system always knows what phase the rotor is in, so it always puts current to the correct winding to produce torque in the desired direction. This fact makes it "feel" just like a brushed motor at low speeds. This does make it a very easy transition from brushed to brushless driving.

A Sensorless ESC does not know where the rotor is when it is stopped, or at very low rpm. This does sound like a big disadvantage, but it is not as bad as it sounds. The ESC just powers up one winding and looks at the other wire to see if it detects movement. If it can't tell, it just steps the power to the next winding in the desired direction. In the worst case, the motor shaft could turn backwards up to 1/2 turn. With the gearing in most cars, it is almost un-noticable. This "stepping" of the motor will continue with more and more current until the motor turns fast enough for the rotor turning in the coils to generate a voltage that the ESC can detect to know where the rotor is. In my MM5700 setup, it takes to about 1 mph for this detection to occur. But the stepping is so smooth, you can creep the car around at such a slow speed, that it is really no concern at all.

So once the car is over 1 mph, both ESC types are able to drive the correct winding to ensure torque in the correct direction. Most older sensored systems, like the LRP and Novak ones, run on fixed timing. This again makes it feel just like a brushed motor. The sensor tells the ESC when to switch to the next coil, and it happens at the same toror angle every rotation, no matter what the rpm, if anything, the delay of the electronics may cause the timing to get a little later as rpm climbs. This is compensated for by advancing the timing of the sensors. This can get the top end power back, but at a loss of efficiency at lower rpm where the timing advance is not needed. All sensorless ESC's require a fairly powerful microcontroller unit to detect the rotor back EMF pulses and calculate the proper timing pointfor switching to the next coil. This has a side benefit of allow it to actually calculate timing advance as needed when rpm climbs yet not having too much timing at low rpm. This makes a good sensorless system a bit more efficient, and capable of a little wider torque curve for a given motor. There is a slight bad side effect though. The changing timing can make the motors power climb a different amount for a given trigger pull depending on the rpm and how fast the revs are changing. Think of it as a turbo charger that might not always be spooled the same amount. The better the ESC software, the less this effect. The latest 1.17 firmware update on the Mamba Max has made it so smooth, I don't think it has any real disadvantage over any ESC, whether it is sensored or not. The timing advantage of the sensorless is no longer unique. There are a few new ESC's that have all of the smarts needed to run sensorless, but also have a sensor port. I know that the Speed Passion GT is still using the dynamic timing of the sensorless control, but with the base timing coming from the sensors. This is a true "best of both worlds" capability, if it has been programmed right. Virtually every car enging has been using dynamic ignition timing for many years. The idea is the same.

For me, there was one more advantage to sensorless. You only have the 3 heavy power wires to the motor. In my XXX-T, the motor is sticking out the back, and the tiny sensor wires could be right in the path when being hit from behind by another car. If your ESC depends on the sensors to run at all, a tiny hit on the sensor harnbess could mean the end of your race. The tiny startup issue is far less of a concern, especially since the latest firmware.

SO... if they cost the same, it is a tough choice. The hybrid setup like the Speed Passion GT sounds great, and if it could switch to full sensorless in case of a sensor wire break, It would be the best design, but it also costs far more than the competition. Nearly $300 for just the ESC. The Mamba Max makes as much power as anything intended for a 1/10 car, at a fraction of the price, and it is far more flexible with the ability to run 3S and even 4S it is being used even in 1/8 conversions.

The motors are a whole other story. Sensorless motors are CHEAP. Actually cheaper to make than a brush motor. The Castle CM36 motors were designed with no regaurd for rules. They make gobs of power and give you a wide choice of rpm ranges with just 4 motors. A sensored motor requires a PC board with the hall chips on it and in most cases, a way to adjust their timing relationship to the rotor. And some of them even have a separate set of magnets just for the sensors. So even if you were not looking at rules, the motor must cost more. Now add in the ROAR rules that limit the internal design and they actually limit the power that can be produced for a given rpm range. This makes it so you can make more power with a lower turn motor, but then the rpm range goes up and up. So to get the ideal fit of motor rpm to road speed for a given car and track layout, they need a wider array of motors to fit the needs. Other companies like Feigao also make a huge array of sensorless motors, but that is to cover a wide range of battery vlatges and going in planes and boats where you can't (or don't always) use gears to get the speed range needed. For 2S or #s in a 1/10 car, there is really no need for anything besodes the 4 CM36 motor KV's.

So, if I was buying just one motor/ESC it is impossible to beat a Mamba Max 4600 or 5700 to be able to drop into almost any 1/10 car/truck and have a system as fast as anything else on the track for about 1/2 the price. You really can't get a good brush motor and ESC for the street prices of a Mamba Max, and now the Sidewinder is even cheaper. For $130 you can get a 4600 system and run as fast as a Mamba Max in any "normal" situation. The extra 30 amps the Mamba Max can handle is rarely needed unless you are doing speed runs with silly gearing on batteries with huge current capacity.

If the Venom really does all they say for just $230, then the Mamba Max might have some competition. I won't hold my breath though. The Mamba Max is a proven system with amazing reliability and support. I have been totally abusing my MM5700 for over a year now and it just keeps going.

[scoob]

I have raced with several different setups. My two T4s are setup currently with one sensored and one sensorless. I have a a Mamba max in one with both 4600 and 5700 motors to choose from and the other is setup with a GTB with 6.5 and 8.5 (sintered) motors.

I think it depends on personal feel as to which you prefer. I've been to tracks where one or the other is preffered by the locals. I personally just feel better with a sensored motor for racing. My Mamba truck is a nice backup though and it does fine with the 5700 on large tracks (it rips) and the 4600 is great on the smaller ones. It may be partly in my head but I just can't help but feel like I'm not totally in controll all the time with sensorless setups. I think it will go back in a basher and I'll just turn that truck into a brushed stock for now.

My Novak does great on the large 1/8th size tracks we have around here with the 6.5 motor giving all the power the truck can use. It will literally flip backwards on it's lid. Maybe a hair less power than the 5700 but not much and is more efficient in my opinion judging from runtimes and temps. The 8.5 is awesome indoors with nice tractability and really just like the 6.5 but toned down a good bit. My Novaks are several years old and when I first went sintered I thought they had lost quite a bit of power untill I figured out that they must be geared much taller than before. I went up 3 teeth on the pinion in both motors compared to what they ran before and they really came to life.

From what I read on most forums I'm starting to believe the smoothness is all in my head but, regardless it makes me more confident in my setup so that's all that matters to me whether it's for real or I'm imagining it hehe.

So I believe it's up to the user. Just thought I'd throw out a different opinion from someone who actually prefers a sensored setup to the Mamba for racing. :)

[ElectricThunder]

I think something that is to sensored motors' benefits is A) the many different winds available and B) the design limits power and torque of the motor moreso than a mamba motor. So you're not overpowering the the vehicle on the track. Yeah, sensorless stuff can be competitive, but from my experiences with both types of systems just horsing around, I find that I need to be more skillful with the mamba max setup. The Novak seems easier to deal with, probably because it's less power too.

just my two cents.

[GSMnow]

On our tighter track, I agree, a sensored sytem would probably be easy to handle in a 2WD. My truck with the MM5700 was (as another driver said it) "Like driving a Viper on ice!" When you think about it, the trigger only has so much travel from off to full throttle. If it goes from 0 to 200 watts, it has finer control than when it goes from 0 to 500 watts. But it is not even just that simple. On the Mamba Max, the trigger is basically a voltage control. So when you pull 50% trigger, the motor wants to turn at 1/2 of top speed. If the car is going that speed (say 20 mph) then it pulls very little current, but if the car was only rolling at 10 mph, it will pull a huge amount of current and try to make the wheels go 20 very quickly. This is part of the "out of control" feel that takes some getting used to. In theory, you could see 150 amps at half throttle under the right load conditions. Punch control tries to help, but it is far from perfect. You really do need to train your trigger finger to get the most out of a Mamba Max. I have been racing it a year, and I am getting better, but I think it just may be too much for 2WD. In my 4WD it is a whole different story. The slipper clutch is very progressive, and it slips at just about the same point as a very good set of tires. It never even hits at a wheelie and it rips from a stop to 40+ mph without much drama. In last nights race, I took second out of 7 in mod class. The winner was a sponsored B44 with a hand tweaked bruch motor and factory team EP4600 NiMh cells. We were a dead match on all of the acceleration sections. He used about 3200 mAh for a 5 min heat, I only used 1600 mAh. So the efficiency is double. After the race, both on the packs from the race, we did a standing start drag race. It was an absolute dead heat. We were both at complete traction limit for the entire straight. The cars were never more than 1 foot apart all the way to 35+ from a dead stop. And going into the sweeper, I actually held the bottom and took the lead into the infield. We only planned a drag, so he didn't follow for the lap. He plain out drove me in the race. I still need to work on setup. My car is transitioning from push to loose without much warning. The other driver tried it, and thinks it may be a step in the power curve causing it. I don't think so, as it is not always while increasing throttle. I disconnected the rear sway bar, and it pushed more in general, but would still snap out in a few turns. I may end up going to a softer setup in the rear to help keep the rear tires planted. I can't really go stiffer in the front as it is floating the rear tires in the fast rough areas. His B44 felt a little softer all around, and he was certainly heavier, which I think may also help when the track gets rough.

One little thing about the Mamba Max (and probably any sensorless) is that the timing changing does make the amount of power for a given trigger and rpm is not always exactly the same. Since it has to detect and calculate the timing, it may be a hair off from time to time. Brush motor and sensored systems don't have this potential timing jitter. It is small, but when you are trying to run at the limit of grip, it could make a tiny difference. The performance to cost ratio still makes the Mamba Max a crazy bargain. It give you world class team racer mod power at a price cheaper than a good stock brush system. I think the slight rubber trigger is well worth it. I have spent nothing for motors or ESC in over a year of hard racing. I burned up 3 stock motors in just 3 months. There is no comparison.

[lennythe]

I have raced with several different setups. My two T4s are setup currently with one sensored and one sensorless. I have a a Mamba max in one with both 4600 and 5700 motors to choose from and the other is setup with a GTB with 6.5 and 8.5 (sintered) motors

So I believe it's up to the user. Just thought I'd throw out a different opinion from someone who actually prefers a sensored setup to the Mamba for racing. :)

I also have 2 t4's, one novak and the other with the MM. My novak is a 13.5 and I just bought a 8.5 (not sintered on purpose) that I have not run yet. I am hoping it will act like a 8.5L. But if I were to guess I will run that on the MM. I have worked on my throttle fingure with the max and feel now alot of my problems are just too much top end and not making the corners on good lines because of it. Between the 2 I would rather run the max. Way more options to play with. Brushless basically took the tools out of our hands, no more cutting coms and soldering brushes. Novaks take all that out with the plug and play. At least with the software on the computer I still feel like my tuning a motor. With brushless and lipo's now I need some thing to do. But that's just me.

[GSMnow]

The more people I talk with (and let drive mine) it seems more and more that the biggest "problem" you have when racing with a Mamba Max is that it truely has too much power. When even the weakest motor can dump 500 watts on demand, it is not that big of a surprize. I have already sent my request to Patrick at Castle for a true current limiting setting. I think the reason it is not there is that the Mamba Max does not actually measure the current. There are two ways to measure a large current. The cheap way is the voltage drop across a know resistance, but this means having an intentional known resistance in the power path, not a good option when you can peak to 300 amps. The other way is to use a hall effect sensor around the wire. This is obviously more expensive but does not add any more resistance. The Eagle Tree data logger uses this setup. I did experiment with series R on the 3 motor wires, and I did like the result in my truck, but it had no adjustment, it was good for a loose track, but then too slow when the track was good. I made a lighter limiter (less R) which worked great on a high bit track, but then it still was too touchy when it got dusty. This still didn't truly limit current, it only made it a little softer when you pull too much trigger for the motor speed right now. It gave it a little rubber trigger effect so you didn't have to be as precise. So far the best solution has been putting the MM5700 in a 4WD. now I use ALL of the power.

[SpEEdyBL]

I wonder if 2s A123s would do the trick. 6.6 volts instead of 7.4. Another way to limit the current is just to set the low voltage limit on the esc higher. This is almost the same as what a current limiter would do although you would notice a performance drop near the end of the run, as it would get easier to depress the voltage on a weaker pack.

[lennythe]

About the too much power, my friend ran a novak 5800 with the sintered rotor and all went smooth and he won the main. I am looking forward to my 8.5 in my T4. On the clay track where I mainly race, the castle motors, even the 4600 are just a little to crazy. That being said, they look like a good time in the 4wd's. On a loamy loose dirt track running pins, I thought the 4600 was about perfect. It seems a little funny that for the price we get too much power, at least in certain applications. I have not yet turned the timing down on the 4600, that is my next adjustment, but all in all I do like the motor. If I don't like the 8.5, does anyone know of a 4200kv or so motor? Other than the big brushless names, I really don't know any out of the mainsteam.

[GSMnow]

Check this one out

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLWZ7&P=6

Too bad it has a 5MM shaft though, but look at the price.

[kufman]

Check this one out

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLWZ7&P=6

Too bad it has a 5MM shaft though, but look at the price.

The 5mm thing can be fixed

http://kufman.com/img/rc/Comm_lathe.jpg

[ElectricThunder]

Hahahaha! Ghetto, but effective I suppose huh? What motor is that?

[crazyjr]

The 5mm thing can be fixed

http://kufman.com/img/rc/Comm_lathe.jpg

Very cool thinking, You did use the diamond bit right? Hope the shaft can handle the stress, i think you might have lost some hardness

[crazyjr]

No, there's a LOT more to the rules than just rebuildable, 2 pole, and Wye wind.

They must be slotted, salient pole wound motors, and have the same inductance as the Novak motors AND the exact same rotor size as the Novak motors...

Patrick

Ok, I didn't know there were other variables. How can the C-40 hackers be legal? Aren't they delta and air core as well? (Like the CM-36 motors).


ET, I read in a mag somewhere, I think RCCA, that the rotor was novak sized. I might be wrong but thats what i recall.

[GSMnow]

The "legal" Hacker motors are built to the ROAR rule book and look just like a Novak with the center ring and lamination stackm etc. I held one in my hand, it is an E40 (not C-40) and it has a nice "Made in China" sticker on it. I am betting it is a Feigao OEM. But I have to admit, the build quality looked beautiful. Much nicer than the Feigao sensorless stuff. The new Losi sensored motors are evidently coming from the same China OEM. There are torn down comparison photos on another forum.

[Mister-T]

Speaking about motor building, I have few picture of a torn down Tekin motor (slotless)

http://www.rctech.net/forum/showpost.php?p=4493879&postcount=152

[ElectricThunder]

Ok, I didn't know there were other variables. How can the C-40 hackers be legal? Aren't they delta and air core as well? (Like the CM-36 motors).


ET, I read in a mag somewhere, I think RCCA, that the rotor was novak sized. I might be wrong but thats what i recall.

It's not. The mamba is 17mm in diameter while the Novaks, at their largest, are 14mm (bonded rotor; largest sintered is 13mm from Novak). Their lengths differ as well.

The Novaks are "380 size" rotors, while the mamba is between the 380 size and the "540 size" rotor. I could attempt to take apart my 5700 and double check...the endbells don't really wanna come off though.:D

[GSMnow]

17mm does sound about right. I had my 5700 apart to clean out all the dirt. The rotor is not very long, maybe 20 mm, but it is fat and it has aluminum end caps on the magnet. The lamination stack in the spec legal motors takes up a lot of the room. So to get enough wire in, they did have to shrink the rotor since the outside diameter is 36mm, there is nowhere to go. The windings in the Mamba Max CM36 motors is just a pack of wire filling the whole space from the rotor to the can. The can is very thin aluminum, I'll give it 1mm. The air gap is probably also 1mm (could be less) so that gives...

36 - 2 = 34 mm can inside dia.
34 - 17 = 17 mm /2 = 8.5 mm between rotor and can wall.
8.5 - 1 = 7.5 mm around the whole inside of the can to pack wire. They use many very fine strands so there is very little wasted air space as well. The wire pack fills the whole can and is just glued in, no room for any screew to pass by, let alone the metal laminations.

[GSMnow]

And back to te original topic...

I took second in the first qualifier, but that was not good enough. I broke a diff outdrive in the second qualifier, and I was barely able to drive, I turned 47 and 36 seconds on my last two laps. Not only was there no drive to the left front wheel, the dog bone caught on the hinge pin and kept jerking the car to the left, and I run the diffs tight enough that the torque on the right front also pulled it left quite a bit, but the 11 second faster second lap sure shows I was getting a little feel for it. I got the diff fixed, but found myself 4th on the starting grid. I was sure glad I had a decent first qualifier to fall back on.

I got a good start, moved up to 3rd for a bit, but dropped back to 4th for almost the first half of the race. I even made a small mistake and was down to fifth. Now the fun part. They decided on a 7 minute main. All 7 cars were running strong at 5 minutes. But it only took a half lap more and we had our first drop out. I am not sure what did him in, but he was leading in a B44 and then off. Not even a full lap later the next B44 dropped out. This one was an overheated brush motor that melted off the brush wire from the hood. Sure, his 9 turn beast makes close to the power of my MM5700, but it could not run for the extra 2 minutes at this level. I now found meself up to second place behind the last remaining B44, and he is running a Novak brushless system. With my early trouble and traffic, he did come around to put a lap on me, but at 6 to 7 minutes, I was able to run right with him, and he didn't pass me for the full lap up until a corner worker stepped right in front of me as I was air born off a small jump. The B44 also ended up running into me, but he got away just a tick quicker, and I had to chase him down for the last 3 laps. I stayed right with him, but I could not get around to get my lap back.

So first and second were brushless when we went to 7 minutes. I did some throttle curve tweaks based on the suggestions from one of the top drivers. It did "feel" a little better, but something is still just not quite right. I also think something is binding in my front gear box after the 12 minute diff rebuild. I will have to tear it back down and go over it all again. My fastest lap times were very close to my qualifying times. I got into the low 26's, I just can't hit those 25's that the TQ got. I think I could have with the JConcepts tires on the back. I had Losi X-3000's, and they just didn't seem to have as much side bite, but they actually did pull great in the straight line.

[racerrandy]

The trinity pack is crap. I've heard it from a few sources. They've used cheap cells like they used a cheap motor. They're using their name to carry them afloat the top right now instead of developing new stuff and leading the way in quality and performance.

I still like my TrakPower 4900 gold-cased batteries. You have to use their proprietary balancer (or something similar) but it works. And it works well.

-Eric


Crap!!! I wish I had done some more research before I bought my trinity pack last week. I got it for the cut off, so I can run it on my other speedo's as well.


Randy

[Mister-T]

17mm does sound about right. I had my 5700 apart to clean out all the dirt. The rotor is not very long, maybe 20 mm, but it is fat and it has aluminum end caps on the magnet. The lamination stack in the spec legal motors takes up a lot of the room. So to get enough wire in, they did have to shrink the rotor since the outside diameter is 36mm, there is nowhere to go. The windings in the Mamba Max CM36 motors is just a pack of wire filling the whole space from the rotor to the can. The can is very thin aluminum, I'll give it 1mm. The air gap is probably also 1mm (could be less) so that gives...

36 - 2 = 34 mm can inside dia.
34 - 17 = 17 mm /2 = 8.5 mm between rotor and can wall.
8.5 - 1 = 7.5 mm around the whole inside of the can to pack wire. They use many very fine strands so there is very little wasted air space as well. The wire pack fills the whole can and is just glued in, no room for any screew to pass by, let alone the metal laminations.

Pretty much like this

http://uppix.net/4/5/9/b91afc08d94b65d0b678ce75a1475t.jpg (http://uppix.net/4/5/9/b91afc08d94b65d0b678ce75a1475.html)

http://uppix.net/a/c/6/e6308ad44f37f1dbbccc19344bfb7t.jpg (http://uppix.net/a/c/6/e6308ad44f37f1dbbccc19344bfb7.html)

http://uppix.net/f/9/a/0e1fabc0ff7984a0fa3310cb10d80tt.jpg (http://uppix.net/f/9/a/0e1fabc0ff7984a0fa3310cb10d80.html)

http://uppix.net/b/1/0/cb8384d364a1e95edc1e0b45a5afett.jpg (http://uppix.net/b/1/0/cb8384d364a1e95edc1e0b45a5afe.html)

http://uppix.net/3/8/1/ba85c87241b3030322a4acc0ff9a1tt.jpg (http://uppix.net/3/8/1/ba85c87241b3030322a4acc0ff9a1.html)

[ElectricThunder]

Wow. That's a lot of wire packed into that motor. Lots of finer strands it looks like. The rotor looks pretty sizeable as well. Looks comparable to the 540 feigao rotors I've seen.

Nice little metal shield they put over the windings in the front of the can; cheap insurance that a screw doesn't short something out.

[Mister-T]

It's not really a shield, in fact the front endbell is unscrewable.
Untight 2 grub screw inside the purple can then use the 2 mount screw at lever and unscrew it.
This Tekin motor is the easiest motor to dismount i have ever had. Very clean, finish egal if not superior to Speedpassion motors.

I want to buy another one, I wonder if a CC CM36 is easily resellable...

[SpEEdyBL]

Hey I'm still thinking of getting one of those motors for some high speed bashing with 3s and 4s packs in my xxx-4. What kv and battery are you running, and what sort of speeds are you getting?

[Mister-T]

I'm running the 4800 kv one on my RC10T4 , speed is decent but there is a large gearing choice some people are running them up to 32 teeth, i'm running 3600 and 4200 intellect battery with 6 or 7 cells. On 7 cells I hit the grip limit on my local track.
According Tekin president they have been able to reach a stupid 150 000 rpm on bench test, but the official recommend to not exceed 100 000 K rpm. I guess a Tekin 362 (6200 kv) with a 3S battery will be really fast ...
http://img46.imageshack.us/img46/694/cimg1170qn8.th.jpg (http://img46.imageshack.us/my.php?image=cimg1170qn8.jpg)

[SpEEdyBL]

Thanks. I think I will probably go with the 3700 then so i can safely run 4s as well. Even if the the 4800 one could handle 4s, it would be just be a little too much to rpm for me to deal with. Even a 4500 kv 380 motor just on 3s is a handfull in my experience.

[GSMnow]

Saturday night's race was a fairly small turnout. Not sure why but for my first real race back in 3 months I only had 2 other 4WD's so they lumped us with the only two 19 turn (I think they were both brushless 10.5's) which were a 2WD buggy and a stadium truck. Needless to say, the 3 4WD's took 1-2-3 in both qualifiers, and we actually put 2 laps on them, which was part of my problem. The truck didn't like being passed.

The leader was a B44 running Track Power LiPOos and a Murph Dog Racing prepped 7.5 turn brushless motor. I think they are using the Speed Passion stuff, but I am not sure, it only had the Murph Dog logos on it. I have met the guys from Murph Dog and they know what they are doing, and it shows. My Mamba Max 5700 setup on LiPo clearly had more raw power, but over 90% of the track, he had as much power as anyone could use, so I only had a slight advantage for 5% of the track. My car ran flawless all night and nothing broke at all, I was just plain out driven in the tighter sections. I actually qualified 3rd, but only 2 seconds off of second, who was only 15 seconds off of first, so it was a good run all around. The 2nd qualifier was another B44, so I was the sole Losi in the 4WD fight. Surprizingly the other B44 was running a brushed mod. I have no idea what wind, but he sure had a lot of rpm available. Again, I could out pull him i the few places the track could take the power, which made for 4 really fun laps where we were on each other at every turn. In the second qualifier, I really started to see a pattern. I would pull out 6 to 10 feet on the long straight, then hold my own around the fast sweeper, but then the 180 left to 180 right section would give it all back up again. At the same ground speed he was able to run a smaller radius curve as my car just pushed a tiny bit wide either making me take a longer distance, or I would just have to slow down a tick more to take the tighter line.

So starting from the 3rd grid space, I knew I had some work ahead of me, but when the start of the main came, there was only one car ahead of me on the grid. The brush motor needed service, and he had trouble getting back in, so we started a 4 car main with me now in second. I did all I could to stay with #1. I could close on the fast sections, but as the race went on, he could just cut those tighter lines and make up for my better performance on the straight. I took a very comfortable second place, just a hair over a lap behind, I let him by clean and again tried to stay with him, but it was not to be.

Afteer looking over the car, and even adding some front cambe, we did some post race testing. I had the #1 drive run a few laps, he was shocked at the acceleration and even after a 7 minute main, he way over shot the triple and flat landed it after the 3rd hill. He knew I had a power advantage, but didn't realize how big it was. After 3 laps to dial into the different car, he had an idea. We took turns going through fast turns and watching the car as it loaded the suspension, and OMG!!! The load into the front tires with the caster was actually pushing the front wheels towards straight. It was losing nearly 1/2 the steering travel. It was my new Kimborough servo saver. The spring just could not hold the steering angle to the wheels. This is starting to explain why it didn't seem to respond to the camber and toe adjustments. When I got more grip, it actually just straightened the steering more, resulting in about the same curve radius and total lap time.

I spent a few hours after the race and put a new factory Losi servo saver on and also adjusted the linkage to reduce the torque on the servo. I also put my repaired Futaba metal gear high power servo back in. It seems beter when I push on the wheels, but I won't know until I get to drive it on course again.

Even with the steering issue, my times were not bad. Most of my laps were 22's to the odd 24 when I crashed, but my fastest lap was a solid 21.7 seconds. The leader ran mostly 22'2 as well, he was just more consistent.

My new Mamba Max ESC is running my beat up MM5700 like new. It has gobs more power anywhere on the track. The other comment I got was that it needs a bit more brakes. He is used to being able to dive in deep and just hit the brake at the last second to make the turns. I have my brakes diald down to just 30% so I will try 40 to 50% and see if it does the trick.