KF Drive Belt Tension

[Jay Smith]

I was just wondering if anyone can help me. My KF seems to be going through drive belts every month or so. I'm not sure how tight to run the belt tension adjustment on the motor mount. I've tried both low and high tension and still have the same problem.
I thought running it tighter would stop it slipping, but if it creates resistance in the drivetrain or stretches the belt, the teeth won't line up with the teeth on the pulley and diff.

The only thing I can think of is to run my slipper clutch much looser to prevent the belt from slipping? Any other ideas?

Thanks,

Jay.

[Craig1983]

I was have the same problem with mine. Was going through belts every few weeks. I was running out of ideas what was causing it. After stripping my kf down to fit a new belt one time I checked every thing I could check. It turned out I had a fault with my chassis. The holes at the back that hold the gear box in place where not the same distance apart. There was a mm difference so it was causing the gear box to not sit straight and faucing the belt to pushed over to one side and rub on the top deck.

Hope this helps you out. It's worth looking at just to check.

[juergen_jl]

Is it possible that your belt "may touch/rubs" at the top deck?

What did I:
- please place all (both) shims on the left side of the rear diff, so that it generates a bit more space between belt and top deck.
- Additionally "break" the corner at the left arm of the top deck, but only the upper left side.

Hope that helps.

My KF now survived 2 races and the belt looks used, but in good condition.

[Jay Smith]

Thanks for your replies, I've checked the alignment and all looks ok. There's plenty of clearance between the belt and top deck. I think my problem is that belt slips before the slipper clutch under hard acceleration from standstill.....
I'm still not sure how tight to run the belt tension, but hopefully loosening my slipper clutch a bit will solve the problem.

[wingers]

Jay,

I’ve obviously not done enough running to comment on wear rates but the belt won’t be designed to slip at all. If that’s slipping before your slipper then it will damage the belt quickly.
I’ve done the same as recommended above and fitted all of the shims (4 in my case) on the left of the diff for extra clearance, but I would definitely make sure that the slipper is the first point to give.

It’s worth checking that you haven’t rounded off the teeth on the diff and/or front pulley if you’ve already had a belt go before too.
As for tension, I can only recommend checking it with some of the others at the club. It seems to be about 75% KFs at the moment so there should be plenty to compare with!!

Wingers