Chain Slap?????

I own a 2009 wr 450 and i noticed alot of chain slap coming from the drivechain. Does anyone else have this? I have a brand new Renthal sprockets and a Gold series o-ring Renthal chain adjusted fairly well, Do i need to tighten more? thank you

I've noticed on my '06 that most of the chain slap comes from the swingarm buffer pad rubbing on the swingarm. Some people glue there's down to lessen the noise. Hope this helps. Maniac

On my 07 450,I glued the buffer pad and slid a pvc pipe over the sub frame next to chain.Works perfect.

Your chain is probably too loose. This seems to be a common problem.

The procedure to adjust the chain is the same for all WR450F's. The slack dimension tolerance may be different between model years however. Check your owner's manual for the correct slack tolerance.

I'm sure that you are familiar with the procedure to adjust chain tension. However, just to ensure that one critical point is not overlooked, I will remind you that the slack tolerance dimension is NOT the difference between the measurement shown in the illustration contained in the Owners' Manual while the chain is at rest and the measurement of the chain while the chain is under tension. In the old days, when everyone rode Husqvarnas and CZ's, that was the way chain tension was measured. If you calculate the chain tension using this method, your chain will be too loose.

The correct way to measure the tension on your WR is to record the distance from the top of the bolt in the chaffing pad which is located on the top of the swing arm up to the BOTTOM of the chain. This dimension should be (for the 2008 WR) 48 - 58 mm or 1.9 - 2.3 in. Look closely at the illustration in the Owners' Manual to see my point.

I adjust my chain this way and I do not have chain slap and I do not have marks on the inside of the subframe or main frame near the countershaft sprocket.

I find it easier to adjust chain tension by removing the lower shock mounting bolt, and stuffing my toolbox under the rear tire. This places the swingarm level, which puts the chain at it's tightest position in the suspension travel. Then tighten accordingly. It's super easy, and works perfectly. Maniac

Chian slap = you ride 2 slow.

Chian slap = you ride 2 slow.

Lol,your prob. right,thanks boys i'll try some things

I had a loud chain slap noise from my '06. It was so bad I thought it might have even been a cam chain. Fortunately for me it wasn't and I recently replaced the swingarm chain guide as well as the roller and now it's much quieter.

Definitely a loose chain. The only problem is that I sometimes have that problem while out on a long DS ride.

I also installed a TM Designworks chain guide and slider (top of the swingarm) and they are a little louder than stock.

trailhead:ride:

A mod for the earlier modes was to remove the screws/washers holding the buffer pad to the swing arm. Place them upside down in about a 9/16 socket and tap them until the washer is cupped, then reinstall the screws/washers. The cupping helps hold the buffer/guard tightly in place. Worked great on my 02 and 03.

No washers on the newer ones, so you have to glue the buffer pad down with some silicone. Maniac

I just bought a used 05 wr450 and took it on a maiden voyage today. The sprockets and the chain look like they are in realatively good shape. The chain is set right. I am getting a lot of noise from the chain. Happens most when I am decelerating down hill and off of the gas and I hit the back brakes ( both with the clutch pulled and released). also a little bit in the beggining of acceleration. lot of slapping going on, I've only heard this kind of noise on bikes that had way to loose chains or worn out sprockets. DUMBFOUNDED

I just bought a used 05 wr450 and took it on a maiden voyage today. The sprockets and the chain look like they are in realatively good shape. The chain is set right. I am getting a lot of noise from the chain. Happens most when I am decelerating down hill and off of the gas and I hit the back brakes ( both with the clutch pulled and released). also a little bit in the beggining of acceleration. lot of slapping going on, I've only heard this kind of noise on bikes that had way to loose chains or worn out sprockets. DUMBFOUNDED

Even though your chain might appear to be tensioned correctly, if it has uneven wear - tight in some spots, loose in others - you are going to get chain slap. Definitely do the "silicone under the buffer pad" mod as that helps muffle the slapping sound, but IMHO, a new set of chain/sprockets is a good way to start your "new" ownership experience with the bike. It will also be a data point for future troubleshooting of strange noises.

Chian slap = you ride 2 slow.
This is kinda what I was thinking. If you're on the gas, there is tension in the top of the chain and slack on the bottom. Vice versa if you're coasting, braking, decellerating. The WR has lots of engine braking and it's easy to put yourself into that situation. Not me, of course :smirk:

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