chain slap???? at low RPM

i have about 2inches oh slack in my chain and i hear a rattle or slap if i let the rpm get to low and then hit the throttle. i read something that said when they fixed there chain slider it fixed the slap or rattle. i have a 01 wr426f and was thinking i need a new chain for it because i cant adjust the chain much to make it tighter. the manual says something like 2in. of slack is want you want and im wondering if thats too much? also what size chain should i buy if i get a new one? what brand is cheap and good quality for a chain? thanks

First off-make sure that the rear Hub's bearing's and seals are good , if there worn your $200 investment in a chain and sprocket set will be short lived. The stock chain is a D.I.D. v520 o-ring 114 links, vortex or ironmans are good sprockets. Stock gearing on a 06wr450f is 14/50, your 426?, you order the chain 120 links and grind a link out to the required links needed for your gearing change! What kinda shape are the adjuster bolts and nuts, change them out with ss metric's grade 8. Make sure you don't strip the heads on the sprocket bolts.

The slap comes from the plastic guide that goes around the front of the swingarm. I put a thin piece of weather strip on the swingarm and the slap has gone away.

I would like to see a picture of that.

The slap comes from the plastic guide that goes around the front of the swingarm. I put a thin piece of weather strip on the swingarm and the slap has gone away.

+1 me to

I've a WR450F 08. It makes an awawful clatter under hard acceleration. I thought it was coming from the clutch as stops when the clutch is pulled. It's got less than a 1000 miles on it. After reading this thread I'm thinking it could be the chain.

cheers

I would like to see a picture of that.

you put the weather stripping under the chain slider's, top and bottom of the swingarm.

I put a bead of caulking under mine or se a bead of sealer ..

The weather stripping is just the kind you buy at home depot. I sliced it in half to reduce the incremental height.

As also mention, caulking or bead sealer will work. The intent is to stop the plastic from going up/down and slapping the swingarm. Go out and pull up the front half of the guide and see how much "play" there is. Dual sport street riding really magnifies the issue. That's what got me to make the fix.

r u talking about the whole bottom of the swing arm you but weather stripping on? i have this foam insulation that is sticky on one side that might work well. its the stuff you use to wrap around pipes to keep them insulated.

r u talking about the whole bottom of the swing arm you but weather stripping on? i have this foam insulation that is sticky on one side that might work well. its the stuff you use to wrap around pipes to keep them insulated.

The stuff I used was just typical weather stripping. I sliced it in half to keep the height down. I put this just on the top portion of the swingarm.

IMG_6066.jpg

Yep:thumbsup: You just want enough thickness to dead'n the noise. Have you tried it out?

no i havent got around to fixing it yet. im in the process of replacing the timing chain and yz timing my bike. i took the seat, tank, and endine brackets of so now im ready to take the valve cover off. i think the yz timing will be better on my wr426f for me. i liked my old yz426f but i sold it when the timing skipped due to a streched out timing chain and the valves broke and destroyed the head. i swapped the wr suspension with my old yz426 suspension so im trying to make it like my old bike. my wr426f wont pull 3rd gear wheelies like my yz426f did. i think the yz timing mod will help give it the same power as the yz426 had. thanks for your help. ill try to fix it sometime this week.

Wow! Any of you guys try adjusting the chain to the CORRECT tension? Check your owner's manual, 2 inches is too much. 1.5 - 1.7 inches

mine says 1.6-2 inches

Wow! Any of you guys try adjusting the chain to the CORRECT tension? Check your owner's manual, 2 inches is too much. 1.5 - 1.7 inches

No, I try and adjust it to the INCORRECT tension:bonk:

Manual = 1.9" - 2.3" which also equals 3 fingers.

The chain slack is different for the steel framed and Al framed bikes. I own one of each - different specs!

There are many threads on this:

Take the swing arm off for service of the bearings while its off inspect the swing arm under the front chain slider. You may notice a lot of wear in the aluminum swing arm caused by the slider and chain.

either use the weather strip or silicone glue. I have had great luck just gluing the slider onto the swingarm with silicone. this will prevent the wear of the aluminum. it works great and is cheap. Just make sure you get the sider in the correct position before gluing.

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