08 WR450 Chain Slap


15 replies to this topic
  • rcmx67

Posted September 27, 2010 - 10:47 PM

#1

Unless I'm really on the gas my WR does a lot of chain slapping. I checked and as per the manual I have 2 inches of play.

This is irritating. Can I reduce it?

  • GuyGraham

Posted September 28, 2010 - 04:02 AM

#2

I too have an 08, and have also noticed the chain slap issue

I run my chain at 45mm slack (spec is 48-58) which I find helps alot in reducing the noise

  • mweitz

Posted September 28, 2010 - 05:06 AM

#3

I too have an 08, and have also noticed the chain slap issue

I run my chain at 45mm slack (spec is 48-58) which I find helps alot in reducing the noise


My manual (02 426) states that running the chain tighter than spec puts undue stress on the engine.

  • 123BigcoopDawg576

Posted September 28, 2010 - 06:28 AM

#4

My manual (02 426) states that running the chain tighter than spec puts undue stress on the engine.


And a good way to sheer a hub.

If you want to fix the "chain slap" then make sure the rear wheel is lined up correctly (some stock chain blocks are not correct)

Mine were off a good 1/4in :p With the correct alignment (either new blocks or measuring for proper alignment) and running the chain at the correct specs, one will not hear chain slap any more :smirk:

  • mweitz

Posted September 28, 2010 - 06:32 AM

#5

And a good way to sheer a hub.

If you want to fix the "chain slap" then make sure the rear wheel is lined up correctly (some stock chain blocks are not correct)

Mine were off a good 1/4in :p With the correct alignment (either new blocks or measuring for proper alignment) and running the chain at the correct specs, one will not hear chain slap any more :smirk:


I don't know how the axle blocks are for you guys with newer bikes, but the stock axle blocks on the 426 suck. There is no way to torque them without the opposite side "twisting" which puts it out of alignment.

Tusk makes a cheap one that holds it pretty well (but only in red).

If they made it for my bike, I would get the Hammerhead Axle blocks. I just got some cheapish ones off of Ebay for about 30 bucks for my "new" 426 and they look good, and seem to work well.

  • mweitz

Posted September 28, 2010 - 07:59 AM

#6

I just looked at the parts fiche for the 08 and the axle blocks look like mine. I couldn't figure out a way to torque the rear axle without the opposite side "spinning" slightly, which tightens the chain from what you set it at and puts the rear wheel out of alignment.

You can see on these (ebay for about 30 bucks) the axle block will hold the opposite side of the axle much better than the stock one. It still twists a little, but not anything like the stock ones.

Posted Image

  • 123BigcoopDawg576

Posted September 28, 2010 - 09:21 AM

#7

Here is what I picked up from Outlaw Racing Products for $35 bucks. They have different colors which is nice :smirk:

http://www.outlawrac...m/ouraaxbl.html

  • WR450FGreg

Posted September 28, 2010 - 02:30 PM

#8

.
On roadracers we always ignore the swingarm marks and measure the distance (accurately) from centre of axle to centre of swingarm pivot on each side.

This might be a good way to check if the marks on your bike are accurate for a start.

Greg

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • rcmx67

Posted September 28, 2010 - 07:51 PM

#9

Thanks for the feedback guys. I have after market axle blocks. I will recheck the tightness and alignment.

Does anyone know where the chain slaps anyways? Is it on the top or bottom?

  • WR450FGreg

Posted September 28, 2010 - 08:43 PM

#10

.
Under acceleration i would be in tension on top, so the slap would occur underneath the swingarm.

Under a trailing throttle the opposite would be the case.

Greg

  • ajh42e

Posted September 28, 2010 - 11:37 PM

#11

I had that same problem on a few of my bikes and i loosen the plastic swingarm gaurd and cut a small thin strip of foam rubber and bolt it back down. I do this on both top & bottom and it cuts the noise down alot. It was a bike problem when we were racing Motard with small real sprockets. Just my 2cents.

  • rcmx67

Posted October 08, 2010 - 11:25 PM

#12

Thanks. I tightened the chain to 50mm slack and that helped a lot. I might try some of the other suggestions here soon.

  • Dirtnerd

Posted October 10, 2010 - 09:15 PM

#13

I had an 07 wr and i loosened the guard then siliconed it to the to the swing arm (tightened it back up) and it made it quieter. It seemed to me the noise I heard was the guard slapping the swing arm not the chain hitting the guard.

  • klxandy

Posted October 12, 2010 - 07:10 PM

#14

I had that same problem on a few of my bikes and i loosen the plastic swingarm gaurd and cut a small thin strip of foam rubber and bolt it back down. I do this on both top & bottom and it cuts the noise down alot. It was a bike problem when we were racing Motard with small real sprockets. Just my 2cents.

There is some factory foam on the top and bottom of the chain guard. You will noticed the swingarm is getting worn under the chain guards as the chains slaps it against the top of the swingarm. Buy some 3/4" wide thin foam rubber with sticky on one side (I use pro-form) and stick it in the chain guard plastic with the non-sticky side facing the swingarm. This will competely eliminate your chain slap until the foam wears out again. I have a roll and change it out every few rides. It is a poor design but Yamaha knows about it as they install the foam on the chain guard from the factory. There is even a cut out on the guard where the foam stops.

  • rcmx67

Posted October 20, 2010 - 08:03 AM

#15

My chain guard is wearing a nice groove in the top of the swing arm. It's starting to get a bit deep. Is this normal? Chain tension is good but there is a lot of slap going on down under.

Foam is next.

  • Bushdog

Posted October 25, 2010 - 10:10 PM

#16

I HAD THIS PROBLEM THIS IS HOW TO FIX IT! keep tension as per manual! get a piece of rubber about 5-8mm thick and stick it under the chain guard (on top of the swingarm) silicone it all down do it doesnt move (this will stop the chain guard rubbing through the swing arm - it does). this raises the chain guard by 5-8mm and completely takes away chain slap - F$%KING BANG!




 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.