XRAY - Model racing cars

During my past two races at a very high traction track (recently treated), I have had wheel nuts come off in the main.

First time was a month or two ago, running solid in front and 80k diff in rear. The outside front wheel (and hub!) flew off on the sweeper.

During the last race, the rear inside wheel and 4 different nuts came off 4 times--always the same inside rear wheel (a clockwise track). I was using 300k front and 80k rear diffs. I inspected the outdrive threads, they are fine. The bearings are fine (were new too). Tires were GRP velocity hubs, 40 shore both times. I tightened them very tightly, but did not add thread lock.

I am curious what people think the problem is? Any similar experiences or solutions?

I have changed all parts and will use thread lock in the future, but am open to suggestions. Given the high traction, the speed and my axel setups, there was lots of stress on the wheel and transmissions--but this racing!

Thanks in advance,

Sam

Hi Sam,

What brand of foams are you using?
I found certain brands dont fit the hex properly and the acceleration/braking/acceleration, etc pattern causes the wheel nut to loosen itself off.

Worth considering.

Cheers
Andrew

What type of wheel nuts are you using? We use the stainless steel type with serrations on the surface that mates with the wheel. We've not had a wheel come off in 3 years. Most nilock and aluminium wheel nuts can create a problem.

Thanks for the replies.

I am using GRP 40 shore, Velocity rims.

Wheel nut is the stock Xray that comes with the NT1WC.

I will experiement with both suggestions. Thanks.

Sam

are you using alloy or plastic wheel hexes on the axles?

Hi
We had a similar problem last season when the same wheel was coming off (four times). I replaced the plastic hexagons with aluminum ones and forgot that it ever happened. It is quite possible that the various wheels we were testing caused micro damage to the plastic hexagons and would loosen the wheel nut under pressure. I'm assuming this won't happen with the aluminum hexagons.
RCPower

As a follow up, I used thread lock and last 2 races in 45 minute mains I had no problem with wheels coming off.

Sam

Normally when you loose a wheel nut there is a problem with the front drive shaft which causes excessive vibration. Rebuild or replace them.