Jpdanger

How often do you rebuild your ball diff?

After one day at the track, my ball diff already feels gritty.

Tony Newland

iTrader: (53)

Mine last couple months with a 6.5 on high bite before the first hint of gritty feeling....

Your diff is slipping causing the gritty feeling.... sand the rings and rebuild it with fresh grease and set it tighter...

The Racers Edge diff tool is invaluable in setting the diff to never slip but provide the best action

Jpdanger

I tighten it all the way, back out 1/8 turn, and then screw in the lock screw.

Does the lock screw have to be in place before I test the diff?

Tony Newland

iTrader: (53)

lock it all down before twisting it preferrably

NWracer77

iTrader: (1)

First race out with the KF2 last night, my first race back in 6 years. Did okay, my driving skills are a bit rusty but the car was DIALED. I qualified in the B bumped to the A. Changed to the carbon chassis, the car is much more nimble now. Here's the setup I ran last night

Jpdanger

I rebuilt the diff this morning. After one day the rings have grooves in them from the balls. Could the diff be too tight?

Badger5

The dif washers do groove up anyway as they aren't hardened but it does sound like it was a bit tight.
Out of interest what diff balls are you using, I find the ceramic ones too hard and more difficult to get the correct diff setting, the tungsten ones are better and result in a more tolerant diff.
I normally find that 1/4 turn back from fully locked is a good setting to start with, with ceramics or tungsten diff balls. If you had to have the diff tighter so as to not slip then I suspect you had the bellevue washers in the thrust in the wrong order so no or little spring tension.
I normally find the diff lasts several meetings before needing a rebuild, and that's on astro with a 8.5T Thunder Power motor behind it.

Tony Newland

iTrader: (53)

Sure, they should have grooves... thats why after it broken in you'll need to readjust it.

If its rough or gritty like your describing, its been slipping.

Jpdanger

I use the tungsten diff balls. My ring pliers just arrived, so I'll do a complete tear down and reassembly to include the thrust bearing.

Why use this type of diff assembly as opposed to the common type found in AE and Losi products?

Tony Newland

iTrader: (53)

Schumacher invented the ball diff 25+ years ago. I rebuild my diff 3-4 times less than my colleagues. I don't question why haha it just works. And once it's adjusted and locked. It will last a long time end never loosed up

spu83

iTrader: (2)

I think my SV2 diff had over 300 minutes since last rebuild.

Riverbluff

Just FYI. Protek makes an aluminum clamp servo horn that will work. I know the Core -RC ones have been on back order but the protek is a nice alternative. Just mounted one in my KF2 and it fits perfectly

Jpdanger

+1

Losi boy

iTrader: (5)

Just a quick question, what brand wheels will fit front and rear apart from schumacher racing? Proline or de racing?

JsK

iTrader: (10)

The DE Racing rears do not fit. The center is to thick so unless there is more axle showing on the KF2 you can't get wheelnuts started with Schumacher hexes. I have used the DE rears with B5 hexes but of course you lose about 2mm of track width in the rear. The plastic B5 hexes are dirt cheap so I keep a pair as a tuning aid. Other than that I have had good luck with any 12mm wheel in B5/RB6 offset.