Online Build: MRC/Academy SB Sport V2 Sport

[PeterV]

As I build test cars, I'll shoot 'em up as "Online Builds" so you can see the cars go together. For this round, I'm building Academy's new SB Sport V2. I liked the first SB Sport, but the new car promises greater durability and improved performance. Here's the box art, and my bench ready for action:

http://209.2.68.15:8011/pics/Academy_box.jpg

[center]http://209.2.68.15:8011/pics/academy_manual.jpg

Academy's manuals were ok before with their black and white line art, but the new manuals are much improved with glossy paper and fully-rendered color images.

http://209.2.68.15:8011/pics/academy_slipper.jpg

The slipper clutch went together quickly. It's a dual-pad unit, with the pads keyed to the spur gear. The spur spins on an oilite bushing, but the Pro kit will have a bearing, no doubt.

http://209.2.68.15:8011/pics/Academy_slipper_wrench.jpg

To adjust the slipper, a plastic spanner grabs the deeply notched adjustment collar.

http://209.2.68.15:8011/pics/Academy_gearboxes.jpg

The ball differentials use plastic outdrives and are installed in identical gearboxes. Plastic crown gears spin the diffs, and metal-shielded ball bearings keep everything spinning smoothly.

http://209.2.68.15:8011/pics/front_plate.jpg

The front suspension arms mount to a separate plastic plate that provides a little bit of kick-up. The hingepins are captured, so there are no e-clips to fuss with. The arms' bores were a little tight on the pins, so I opened them up with a 3mm straight ream.

http://209.2.68.15:8011/pics/motor_plate.jpg

The aluminum motor plate can be mounted on the left or right side of the car. Note the plastic block that slides over the bearing to capture it.

http://209.2.68.15:8011/pics/batt_tray.jpg

Plastic trays eliminate the need for filing battery slots. Note that the chassis has 12 slots, so you can set the car up with six cells in a row, or as a saddle pack placed fore or aft, or in a staggered configuration.

http://209.2.68.15:8011/pics/servo_saver.jpg

The Sport uses a classsic dual-bellcrank setup with an adjustable servo saver. I cranked the preload down pretty tight, since the adjustment collar will likely be hard to spin once the rack is installed. As usual for a sport car, the bellcranks are bushed...but at least they're nice Oilite bushings instead of plastic.

http://209.2.68.15:8011/pics/chassis_batts.jpg

Top deck and shock towers in place--this thing is going together quickly. It's time for the slow parts now: universals, shocks, and linkages.

http://209.2.68.15:8011/pics/universal.jpg

The universals are basically CVD clones as far as the joint construction goes, but the two-piece stub axles are unique. The taper is force-fit into the outer hex portion of the axle when the wheel mounting bolt is tightened. Kyosho used a similar setup back in the day with a tapered steel stub axle and aluminum "drive washer" (hex hub), which was prone to slipping unless you really socked the axles down. These parts should fare better, thanks to an aluminum-to-aluminum joint and much greater surface area.

http://209.2.68.15:8011/pics/academy_hubs.jpg

The hubs look suitably beefy, and carry larger, more durable bearings than the original SB Sport.

http://209.2.68.15:8011/pics/academy_hub_rear.jpg

Instead of clamping the wheels to the drive hexes with nuts, each wheel is secured by an anodized-aluminum countersunk washer and hex screw (not shown). Vertical ball studs and two mounting positions per carrier make it easy to alter roll center.

http://209.2.68.15:8011/pics/academy_roller.jpg

Ready for electronics.

[joostin421]

nice, i like :D

justin

[lextek]

Not a bad looking kit. Looks like a lot of bang for the buck.

[jchung]

Very nice build! :)

Anybody know where this kit is available online? :confused:

[A4DTM]

i just bought one of these tonight on impulse.. going to modify the top deck and cutout the chassis below the motor to fit my Feigao 540C 9L in it.. i'm wondering how the drivetrain will hold up? the diff halves really concern me.. will the pro have better diffs?

also,
Top deck and shock towers in place--this thing is going together quickly. It's time for the slow parts now: universals, shocks, and linkages.
by this stage i had stripped both ends of my allen key (screws were fine, key was just weak), and don't have any of my tools with me =\

[Cain]

For your modifications, you should pickup some B4 diff springs and try to use those instead of the stock units. You may also want to trim the lock nut so you can do a tighter fit. For the rear axles, put an oring into each so this pushes the bone into the outdrive more and you can limit the droop less so you get much better drop range.

I would also run a modified steering link setup so you can have full throw. I just used a turnbuckle and ball end setup.

I ran this setup (without the B4 diff spring) with a 9x1 and it worked well. the spring modification should give more range for diff action.

[pyro18t]

I like the way this car looks, if I didn't get my xxx-4 G+ this car would have been my next choice in Pro version of course.

Jay

[TRXrevoRacerOS18]

very nice

[philp37]

Hey MRC Now for an encore, give us a truggy version of the SB.

[mustangman05]

nice job so hows it running?

[ilikewing]

nice job, you do great work and our very organized ;)


p.s. nice desk and spare parts..

[Apexs]

any chance of a list of parts used other then the kit ones?
make and part numbers would be great so that im able to find them, thanks

[JeffEmbracedDC]

Nice build. I just ordered two of these kits from MRC on Monday. It seems they're on sale for only 110 bucks! I picked up two figuring that I'd spend that much on spare parts in not too long anyway.

So thanks for the article! It will help a bit with my build for sure.

Any chance you guys know where to get parts in the US?

Also, is there a good line of hop ups (aluminum pieces, titanium turnbuckles, carbon fiber chassis/top plate, etc, etc)?

Thanks, guys.

-Jeff

[crazy4wdracer]

it definitely looks like a nice kit!

[JeffEmbracedDC]

Just finished building mine :) Awesome build!

Issues:
1. The shock bodies aren't designed with a deep enough thread, so the caps don't thread on tight and would easy pull right off in a crash. I plan to use some associated shocks from my old B3.
1. Update! So, just as I suspected, after no more than the VERY FIRST jump, two of the shock bodies completely ripped out of the caps causing a dogbone and dogbone pressure spring to completely dissapear and oil to spill everywhere. This was about a 18" ramp landing on all 4 wheels on fairly soft sand. So the shocks are a pretty huge issue if you plan on doing anything with your car aside from keeping it on a shelf forever.

2. The ball cups were very tight and caused massive binding in the steering system. I had to replace all of the ball cups with Associated cups. I would have used RPM, but I only had blue in my tool box. Also, the RPM heavy duty rod ends are too large to fit on the ball studs on the rear carrier as they would rub on the rear wheels. So, I decided to go with some extra associated ball cups I had laying around. The Associated cups caused a little bit of back and forth "play" in the steering assembly, but at least it's not binding like crazy.

3. On its first run, it was apparent that the diffs became very loose even though I had tightened them down "correctly". You may need threadlocker on the diff screw, and also as previously mentioned, a heavier duty spring (from an associated stealth diff) may be a good replacement.

4. One of the screws holding on a front wheel became loose which of course is a big problem. In this design, the screw must be completely tight, otherwise the CVD will no longer drive the tire and will just spin freely. It's kind of weird, in my opinion. Anyway, use some medium duty (blue) threadlocker on the font wheel screws.

Other Comments:
1. The servo saver seems pretty smooth, although it's a little loose. I'm running a metal geared servo so I cranked it tighter a bit after the first run.

2. The sport kit comes with tie-rods instead of turnbuckles, so I replaced them with some factory team titanium turnbuckles from my old B3. Perfect fit.

3. Suspension parts (arms, carriers, steering blocks, shock towers, etc) seem VERY beefy in comparison to most other 1/10th buggies. I can't tell you how good the plastics are, but as far as molding and configuration of the parts - they look very very durable.

4. Tires seem to be a pretty good pin configuration and a nice compound for general racing/beginner use. Impressive. Much softer than the Tamiya Dark Impact tires.

5. Very impressive body design in my opinion. Definitely "race" style. From a car in this price range I would have expected a much more "toy" type of buggy body.

That's about all for now. This kit seems to be really solid. Especially for the price.

Photo gallery available: http://embraced-dc.com/temp/RCStuff/MRC%20SB%20V2/index.html

[EvaderRacer76]

Does anyone know of any good shocks that are a direct replacement for the stock shocks on the sb v2?

[JeffEmbracedDC]

Does anyone know of any good shocks that are a direct replacement for the stock shocks on the sb v2?

My Associated B3 shocks were a perfect direct fit. Exact same length. Even identical sized shock shafts. I tried some Losi shocks from an XX4 that were a little too long and caused the read CVDs to come out of the outdrives.

-J