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3975dave
19-05-2007, 07:49 AM
Can you stop the diffs melting in an Academy SBV2 buggy???

DCM
19-05-2007, 07:54 AM
if they are metling, you are running them too loose, you need to run them a little tighter, and maybe need to replace your diff screw.

3975dave
19-05-2007, 11:34 AM
Are they upgradeable on the V2 or can you fit some from another car?

Davey G
28-06-2007, 12:15 PM
Hello,

Steel outdrives will be available in just a few weeks. Make sure you use high quality diff lube like Team Associated stealth lube, or Team Losi diff grease. ALso make sure your diffs are tight and that the slipper slips for at least 1 foot on whatever racing surface you are driving on. GOOD LUCK!

DCM
28-06-2007, 12:38 PM
are these being made outside of Academy, or Academy items?

mr emily
11-02-2008, 08:18 PM
Has anyone managed to get the diffs on the sbv2 tight enough. There always a lot of slip.Previously melted lots of them I've mentioned this before to Dave Grabowski with no other suggestions than better diff grease. Someone suggested spring from a B4 , diameter to big. Horizon or whoever the importer is, sent me a new diff that they built and it was no better. Have now purchased the steel outdrives which has helped but I still cannot get them tight enough, nothing like say kyosho or the ones in B44. Any suggestion? Or anyone tried any alternatives.
:confused:
And yes before anyone says it better driving might help. But, someone has to.

Southwell
11-02-2008, 08:24 PM
I never had any problems? Do they loosen or do they stay loose even on a new build? I always slightly damaged the thread on the screw and used some thread lock on it. I have never melted an academy diff.

rcrcman
11-02-2008, 08:45 PM
The slipper is there on any car to protect from diff/drivetrain damage.... you need to loosen the slipper if your having cronic diff problems...I've had no issues with mine at all

mr emily
11-02-2008, 10:19 PM
When i set them up, tight enough so I can't turn the crown wheel with fingers, with the two outdrives held, they slip when in the car and just don't feel right when in the car especially the rear. If you hold the two front wheels and turn the rears, they turn very and I mean very easily. If I keep tightening till the ears on the nut touch the outdrive. It dosn't slip but feels very rough. i have used a variety of silicone ie schumacher assoc and losi. They don't loosen when in use.

I tried it with a loose-ish slipper and the car is just not right.

Southwell
12-02-2008, 07:39 AM
If it's going rough it sounds like the diff balls/trust balls/plates are damaged.
When the original SB came out i ran with without a slipper for the first time and didn't damage anything.

mr emily
12-02-2008, 09:37 PM
I thinks they are damaged now, just because i am running the diffs so tight to avoid slip!!!!

rcrcman
19-02-2008, 07:34 PM
If the diff nut is bottoming before the diff is set, you vae the screw in the wrong side..... also can you feel the spring compressing as you tighten the screw?

study the instructions closely how the screw goes through the correct outdrive piece, they are different

mr emily
19-02-2008, 08:51 PM
Hello

I have the eared nut on the left side of the car, ie in the long diff half. If I recall that is the way the distruibutor built a diff for me. They put a washer under the diff spring, approx 0.5mm thick. Iv'e tried this and it helps.

Looking at the diff, I don' think you can fit the nut in the wrong diff half!.

Keith

rcrcman
22-02-2008, 05:03 AM
you have it right.........

what grease you use? I just got back from a race a couple weeks ago where we ran slicks on an olmost asphalt hooked up surface and my diffs are fine, they held up fine. I dont touch them for weeks..... I would disasseble them and double/triple check everything is per tha manual and use AE black grease on the thrust and AE clear on the balls. sometimes I scuff the rings with a fine sandpaper - 600 grit that will le the balls grip better.... also steel balls grip better than the ceramics, ceramics will wear the rings out quicker. maybe your rings are so badly worn there's no adjustment left

rcrcman
19-03-2008, 03:37 AM
The only other thing I can think of is your putting the shims on the outside of the bearings instead of between the bearing and the outdrive. Installing them like that will blow the gearboxes constantly.... the shim will cut into the gearbox immediately and you'll lose mesh control

j.m.
27-01-2010, 11:37 PM
TC3 diffs fit the SB V1 with a little bit of pursuation. (same as what the bj4 used)

I have found that replacing the screw, thrust race, and tnut with AE tc3 items has allowed me to tighten the diffs considerably. So much infact that grooves were worn into the steel plates by the balls. I've had academy screws break loooong before they reached this pressure.

I think that the weakness of the screw and soft steel plates don't allow the diff to be tightened fully.

All of this only applies to the SB V1, unless anybody knows if the cars are similarenough to have interchangeable parts.

Jon