mamba max 7700kv is getting too mean help!!!!

[rustyrevo]

my mm7700kv is too powerful that my tires can't get a good grip. im about to get a b4 but how can i get traction? please help me

[chilledoutuk]

you see that trigger or stick that makes it go forward on the transmitter try being more gentle with it.

alternatively you could run on less cells or just switch on punch control, buy a tamer motor, use the voltage cut-off to limit power etc etc

[rustyrevo]

you see that trigger or stick that makes it go forward on the transmitter try being more gentle with it.

alternatively you could run on less cells or just switch on punch control, buy a tamer motor, use the voltage cut-off to limit power etc etcbut won't that make the runtime lower? and i can't buy anything for 1 yr if i get a b4. and if i use voltage cut-off i won't use the full pack. i just need more traction

[Associated-08]

Softer tires, traction compound, softer rear shocks.

Mike + Aaron

[ElectricThunder]

If you're using NiMH, you should set the voltage cutoff to 5.4v anyways (especially if you're running IB cells).

Just set the timing to lowest, adjust the throttle curve so all the power doesn't come on at once, and go easier on the throttle. That's about all you can do before going to lower voltage or getting a new motor.

[Associated-08]

4th idea... Steal a brick from ur neighbor and strap the sum ***** on the back. You'll hook up then wontcha.. if that doesn't work then buy a new truck.

Thanks, Mike + Aaron

[ElectricThunder]

4th idea... Steal a brick from ur neighbor and strap the sum ***** on the back. You'll hook up then wontcha.. if that doesn't work then buy a new truck.

Thanks, Mike + Aaron

BWAHAHAHAHAHA! Brilliant!:D

Shifting weight to the back should help some too. What kinda tires are you running RustyRevo?

[Associated-08]

Thanks :)

[chilledoutuk]

what does not make sense is that your saying that your about to get a B4 and then saying you have problems with traction.

What makes you think you will have problems and what car are you having problems with traction on at the moment?

Recently i decided to modify my dirt hawgs as i thought there was too many lugs it turned out to work quite well and now i can wheelie on grass which is a achievement without spikes.

someone else used t4 wheels on his b4 to get more grip but then you may as well just get a T4 in the first place.

If you dont think a B4 will have enough grip pickup a 4wd buggy my cat 3000 works nicely with the 7700 on 2s2p a123 cells.

I personally would get the new associated b44.

[GSMnow]

What surface are you driving on? How big is the area? (longest straight, etc.) Do you have to take jumps?

The 7700 is a seriously fast motor system. I run a 5700 in a XXX-T and even that is geared way low (15 to 86) to keep in reasonable on the race track. Tires are very important and must be chosen for the surface, and there is a trade off between tire life and grip. I ra the Hot Rod Hobbies Shootout event and it was basically a set of tires for every 10 minutes of track time. On the flip side, we were able to pull a wheelie for most of the main straight and the cornering grip was insane.

Punch control is a anice tool for learning to drive it, but it does reduce your control when jumping, I have had to dial it back to just 10 or 20% to be able to lift the nose up if it starts to nose down off of a jump.

Biggest help, gear it SLOW. With the 7700, try the smallest pinion and biggest spur that will fit at all. By reducing the top speed, t makes it so you can use more trigger travel for a given speed. This is not a brush motor and it acts a bit different. Even geared fast, it makes more torque than you can use, so gearing slower does not make it have more wheel spin since it has it already. Instead, what it does is make it so you have finer control over the speed you ask for. Think of it like this. If full open rpm works out to 40 mph, then 1/2 throttle will try to spin the tires at 20 mph, no matter what. If you were at 15 mph and pull the trigger to 1/2, it will suck current and force the tires to go to 20 mph NOW!! and the tires will break loose. If you roll the trigger slower, you can go all the way to full throttle and hit 40 mph as long as you pull slow enough that the truck can match the speed increase of the tires. Now if it is geared for max throttle to go 60 mph, then even 1/2 throttle will yank the tires to 30 mph with force, so now you need a much more careful trigger finger to control the acceleration. Punch control does not limit torque. All it does is slow down your trigger pull to a maximum slope. You can dial it to where a full punch will accelerate without spinning the tires, but then you can never get the tires to spin up any faster. Fine for learing to drive with a really fast car, but it takes away alot of control, especially when jumping.

The other thing I do, but it can cause trouble, is running the slipper clutch just a tick loose. I like to put a body clip in the pinion/spur gear so it can't roll backwards, turn the tires back on the ground and see if the front tires lift. I set it so it can't quite lift both front tires. This reduces wheelies on track but if you are slipping the slipper too much, it will get VERY HOT and you can melt things. This is not a replacement for a smooth finger, just a race day aid incase you get too excited. Make sure your diff is really tight. It should never slip, or it will die a quick sad death.

[GSMnow]

Oh, I forgot to add. I have run my 5700 on 5 cells and it works very well. It tames it down a little yet still runs over 8 minutes in race conditions. With the same gearing I was using with 6 cells it was just as fast in the whole infield and just a tick slower on the fast straight, but it lost about 40% on run time(8 min. vs 13 min.) I didn't expect that, but after I thought about it, it did make some sense. With the lower voltage, I was using much more trigger for much more of the lap, so it is pulling quite a bit more current.

[rustyrevo]

well rite now im running a rustler which has horrible performance so im switching to a b4 which i saw on the track that performed very well with a low turn brushed and had lots of traction

[t3oc45]

well rite now im running a rustler which has horrible performance so im switching to a b4 which i saw on the track that performed very well with a low turn brushed and had lots of traction

You just can't compare a low turn brushed to a brushless. It just doesn't work that way. Of course a b4 set up to the track with less power will have more traction! From what I've seen and my own experience, you can get gobs of traction with the right suspension setup and tires with a rustler. You could just take the time to work out the bugs rather than switch to a new car completely:(

That's just my $.02

[ElectricThunder]

You just can't compare a low turn brushed to a brushless. It just doesn't work that way. Of course a b4 set up to the track with less power will have more traction! From what I've seen and my own experience, you can get gobs of traction with the right suspension setup and tires with a rustler. You could just take the time to work out the bugs rather than switch to a new car completely:(

That's just my $.02

I agree.

[chilledoutuk]

well rite now im running a rustler which has horrible performance so im switching to a b4 which i saw on the track that performed very well with a low turn brushed and had lots of traction

what do you mean horrible performance? are you refering to the handling of your rustler which to me is strange as with 6 cells the weight should be plenty to get some traction and the balance should be ok.

Assuming you have half decent tires. perhaps you could try the hpi geolander tires i find them to work well on most surfaces or i hear good things about the masher 2000's and the moa tyres.

[ElectricThunder]

what do you mean horrible performance? are you refering to the handling of your rustler which to me is strange as with 6 cells the weight should be plenty to get some traction and the balance should be ok.

Assuming you have half decent tires. perhaps you could try the hpi geolander tires i find them to work well on most surfaces or i hear good things about the masher 2000's and the moa tyres.

The Rustler is a terrible handler compared to a T4 or XXXT for example. It's not horrific, but it's no top level competitor unless you do extensive and HEAVY modifications (a la JANG over at URC).

[Associated-08]

Still having problems? Try a cinder block, u can buy them a couple bucks.. Ive tried it before it works.. sandbags work also. :)

Mike

[rustyrevo]

what do you mean horrible performance? are you refering to the handling of your rustler which to me is strange as with 6 cells the weight should be plenty to get some traction and the balance should be ok.

Assuming you have half decent tires. perhaps you could try the hpi geolander tires i find them to work well on most surfaces or i hear good things about the masher 2000's and the moa tyres.
i already ordered my b4 and by horrible performance i meant is that im starting to race and i want a buggy too.

[rustyrevo]

The Rustler is a terrible handler compared to a T4 or XXXT for example. It's not horrific, but it's no top level competitor unless you do extensive and HEAVY modifications (a la JANG over at URC).now you expressed my feelings about my rustler THANK YOU!

[ElectricThunder]

now you expressed my feelings about my rustler THANK YOU!

I have both a T3 (which is down for the count; has been for a year or two now) and a Rustler, so I know from first hand experience what a night and day difference it is going from my T3 to the Rustler. The plus side; the Rustler is a tank, and if it's set up right (not really all that hard, and it will hook up just fine on or off road), it performs just fine for bashing. I'd never race it though.

[scoob]

Biggest help, gear it SLOW. With the 7700, try the smallest pinion and biggest spur that will fit at all. By reducing the top speed, t makes it so you can use more trigger travel for a given speed. This is not a brush motor and it acts a bit different. Even geared fast, it makes more torque than you can use, so gearing slower does not make it have more wheel spin since it has it already. Instead, what it does is make it so you have finer control over the speed you ask for. Think of it like this. If full open rpm works out to 40 mph, then 1/2 throttle will try to spin the tires at 20 mph, no matter what. If you were at 15 mph and pull the trigger to 1/2, it will suck current and force the tires to go to 20 mph NOW!! and the tires will break loose. If you roll the trigger slower, you can go all the way to full throttle and hit 40 mph as long as you pull slow enough that the truck can match the speed increase of the tires. Now if it is geared for max throttle to go 60 mph, then even 1/2 throttle will yank the tires to 30 mph with force, so now you need a much more careful trigger finger to control the acceleration.


This is something I don't see mentioned often but I agree 100%. I have noticed this same thing on all my brushless setups. It's different from brushed motors in this way. Gearing down doesn't really make the system more punchy than it already was unless you were geared extremely tall to begin with, it makes BL more driveable for exactly the reason GSMnow stated.