Chain Slap (WR400F)

I have just purchased a 2000 model WR and i noticed that the chain slaps on the top of the swing arm when maintaining a constant speed. I Have removed and cleaned the chain and set the tension the 40mm (Australian manual Specs). Any ideas on how to get rid of the problem? I'm 65kg, will that affect it?

It is quite normal for a little bit of slap, but being an older model - do you know how old the chain on the bike is? I would measure the stretch of the chain as per manual. If it is still good, some silicone under the chain slider can help a bit. Riding a gear lower (rev more) will help too.

I have checked for chain stretch and it's okey. What do you mean put silicone under the chain slider? I mainly notice the slapping on the road.

Hi rogo I took out the top bolt on my chain slider last week (wr 450 04 model 5.000 km) You will be supprised at the wear on the swingarm. I put a little bit of silicone under the chain slider .Got rid of a lot of slapping noise .Do a search I found it in these forums. Cheers.

Digging up an old thread, but I found it doing a search.

My '98 400 has alot of chain slap! Brand new sprocket (f/r) and a new Chain. Adjusted to 2 inches of slack measured above the last bolt on the swingarm chain guide. If I'm a gear low and cruising it slaps pretty bad. After about a month I've checked the sprockets and they aren't worn down funny (ie, hooked, broken, etc.).

:thumbsup: I guess I should stop being paranoid.


silicon under the slider works well to simply reduce the noise from slapping. you can just lever the slider up and put a nice thick bead of silicon under it.

I have simply put a peice of an old thong (flip flop, not g string) under it and glued it in place. works well

I think what matty said about being in the right gear sounds right. If your in a high gear and the rpm's are way low; when you cut back on the throttle alittle to maintain speed under these conditions, will cause slack in the chain, then tighten up again causing your chain to slap around.

Make sure your motor is turning enough rpms at the speed your going to keep your chain tight on the load side. :thumbsup:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now