Diff Tightness

[DaveG28]

Hi all,

I tend to run my diffs "tight" (eg takes effort to spin wheels in diff action) compared to other people, and was wondering what handling effect this is likely having?

Also, what effect would it likely have to have the front tighter than the rear, would it cause understeer?

I just mean in general by the way, I know it's impossible to give the exact impact with no measurement of how tight the diff is!

[bigred5765]

with the diffs tight in most case, it will cause power on under steer, in the xx4 we almost always ran the front diff slighlty tighter than the rear,

[James]

Tight rear diff causes the rear to skid round as the tyres scrape rather than being free enough to rotate so oversteer but quite handbrakey.

front diff - depends if its diff only, or one way roller, but yeh what carl said tighter gives more understeer.

Generally you should always have smooth balls...

[GRIFF55]

Generally you should always have smooth balls...[/quote]

oooh i say James!!!
Dave this is something i have been fiddling with lately and it does make one hell of a difference to the way the car handles. i like the way mine goes with the front quite a bit more locked than the rear.
Just have a play and see what suits you would be my suggestion.

[DaveG28]

Cheers guys,

I tend to run very tight diffs as otherwise they just slip, especially on the Tamiya, I'm sure I'm doing something wrong just not sure what!!

Presumably it's good to have both diffs similar at least, even if one end slightly tighter for handling, but not good to have them too different?

[RogerM]

Dave, you should be able to build ball diffs to the point they spin as freely as a greased gear diff and not slip. I normally leave them a little loose at first, run the diff in by holding a wheel (car off the ground) for a few seconds then setting it by feel (so when holding 1 wheel and the spur it is not easy, but not impossible, to turn the other wheel). After a couple of runs like that I usually have to adjust them but then they should run for ages as smooth as you like.

Hope that helps.