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What do you mean by boosting a motor?

I've got it dialed in now so it's driving and handling very well. The slipper slips for the first few feet then grips up and accelerates hard with no diff slipping. I am wondering if I used too much grease, and now that it has kinda flung out it's finally working properly.

It sounds to me that things are getting broken in now.

Boosting is an option of (some) speed controls. Check your manual/paperwork to learn all the options/ things you can adjust for performance.

Does that refer to the timing?

I have it at stock (10 degrees). I turned down the punch almost all the way, so if I blip the throttle it reduces the acceleration of the motor and is less likely to strip everything out. The only downside is it's hard to give it that little squirt off jumps sometimes.

Thanks all for the help

Make sure you readjust the diff after half a battery or so after a rebuild, they tend to loosen up a little bit as they break in.


Boost and turbo are settings you can adjust on most mid- upper end sensored brushless combos only. It is impossible on sensorless combos. Basically it's adds electronic timing on top of your set motor timing.

Boost basically adds power up to full throttle and turbo continues ramping timing in after full throttle.

The beauty of it is you can have the smoothness and drivability of a higher turn motor but still have the top speed of a lower turn motor, or just go stupid mental

I made an interesting discovery tonight.

Took out the trans, took apart the diff. The diff balls had embedded themselves almost entirely under the plastic, and ovaled out the holes in the diff gear. The plastic had kinda deformed and the two diff rings were partially sliding on the nylon diff gear. I think it might be time for an aluminum gear...

I'm happy to see the idler is still in great shape though!

cobrakai wrote: ↑Tue May 01, 2018 2:27 am I made an interesting discovery tonight.

Took out the trans, took apart the diff. The diff balls had embedded themselves almost entirely under the plastic, and ovaled out the holes in the diff gear. The plastic had kinda deformed and the two diff rings were partially sliding on the nylon diff gear. I think it might be time for an aluminum gear...

I'm happy to see the idler is still in great shape though!

with the slippage everything overheated and led to what you are seeing ie a melted diff, that's pretty classic. I can also see your slipper is too tight on the above pic (the spring is fully compressed it seems) which certainly doesn't help.

I would recommend AGAINST the aluminium gear, which is a tmaxx-savage-youtube-hero-ish solution to your core diff issue. Just like "upgrading" to a 10A fuse when the 5A keeps blowing up. Build your stealth right and it will work properly even with a hot mill. If you get whatever bling-bling band-aid "fix" a la alloy diff gear in your diff, you will introduce other mechanical problems (diff balls rotate well when stuck in a plastic hole, not so well when stuck in a metal hole), and chances are your diff will still slip after that.

Pull the whole darn thing apart, clean it, make sure all parts are there and in good shape (check your t-nut, check your diff spring), replace the ones that are shot (balls are shot now, prolly rings too, then the gear is obviously bust, well actually you need a rebuild kit AE 3926, a new stealt main gear, and you should be golden with like $15) rebuild it properly with the right fluids (stealth lube main balls, black grease thrust), and it will work - t(h)rust us

With a properly set up diff you should be able to strip the idler gear before melting the balls into the diff gear (unless you do endless doughnuts)

So, maybe I'm misunderstanding something fundamental. It looks like you guys are recommending both slipper clutch and differential adjustments. It sounds like a proper setup has the slipper clutch slipping first, then the tires, then the differential (hopefully never). Is this right?

So if I lock down the slipper clutch solid, and the tires have good traction, something has to give right? Either the diff slips, or the gears strip out. So the slipper is a necessity to prevent damage to the other parts? I always kinda thought it was optional for super loose tracks.

yes, the clutch should absolutely be the 'fuse'. the B4 clutch allows for a wider setting range due to surface area.

the diff setting pretty much is done at the initial setup. then you may have to go back once after running a pack in to tweak it slightly, and then it stays at that setting until it needs a rebuild or the weird off chance the locknut loses some grip.

it sounds like you have found your problem. let the clutch slip for a few feet and your diff will last a long time.

Can you point me in the direction of the clutch parts I will need? Doesn't have to be new necessarily... trying not to break the bank too much more on this guy!

My friend actually has a torque converter clutch on his stadium truck. It's made by Losi. Really neat little unit, fits right on the output shaft and has a fluid filled chamber to transfer power.

if you already have the stock clutch and the top shaft gear is OK, just use that until you glaze the pad.. it should work fine. now that you realize the slipper needs to slip, it should be OK to use, as it was not slipping much before.

updating the clutch to b4 requires these parts:
https://www.ebay.com/itm/Associated-7485-V2-Slipper-Hub-Set-SC10-RC10B44-RC10T4-RC10B4-SC10GT-X-60/172237122507?epid=1901834170&hash=item281a21ebcb:g:2vwAAOSwMNxXWx3c
https://www.ebay.com/itm/Associated-9603-Slipper-Pads-2-RC10-B4-1/352323002945?epid=691258643&hash=item5208166241:g:dyYAAOSw1ZJaxk9A

https://www.ebay.com/itm/Associated-7486-V2-Slipper-Spring-amp-Washer-SC10-RC10B44-RC10T4-RC10B4/381011061058?epid=691292147&hash=item58b6076942:g:KbkAAOSwEK9UKrJn:sc:USPSFirstClass!18914!US!-1

https://www.ebay.com/itm/Associated-RC10-B4-Top-Shaft-ASC9601/232749161419?epid=710155334&hash=item3630ee5bcb:g:eGwAAOSwaMpZozzf

https://www.ebay.com/itm/Associated-9651-48Pitch-Spur-Gear-81T-SC10-RC10B44-T4-B5M-RC10B4/301815432415?epid=1101643374&hash=item46459a04df:g:vNIAAOSwQItUIfEH:sc:USPSFirstClass!18914!US!-1

cobrakai wrote: ↑Tue May 01, 2018 1:13 pm Can you point me in the direction of the clutch parts I will need? Doesn't have to be new necessarily... trying not to break the bank too much more on this guy!

My friend actually has a torque converter clutch on his stadium truck. It's made by Losi. Really neat little unit, fits right on the output shaft and has a fluid filled chamber to transfer power.

Slipper Parts: (all are Associated part numbers)

7485 Slipper Hubs or optional 7495 Vented Slipper Hubs
9603 Slipper Pads
7486 Spring & Washer
6629 5-40 Nut

Damnit I literally JUST bought a new GT top shaft because mine got bent.

One more observation.

When i rebuilt it last time I sanded the diff rings with 600 grit on both sides. Now I noticed the back side (against the outdrive) was shiny and polished, and there was a groove in the diff ring. Looks like it was slipping on that surface. Anyone heard of that?

You can also do a multi plate set up with the VTS slipper conversion, you'll still need the parts jwscab posted earlier.

https://www.towerhobbies.com/cgi-bin/wti0001p?&I=LXCBFG&P=ML

Using a little stealth diff lube between the ring and outdrives helps prevent the rings from slipping on the outdrives.