axle blocks 2009 yzf

hi guys this may sound like a stupid question but are the axle blocks supposed to be diffrent sizes on the 2009 yzf 450 as mine are. the one on the brake side is much bigger than the sprocket side.also there are more notches on the brake side there is 11 and ond the sprocket there is 9 is this normal as it does seem to be a little odd

The sprocket side has the lip to hold the axle. The axle blocks are really just a reference, you should measure to see how close they are. Make sure you always count the slashes from the back of the block forward.

Yes the axle blocks are different on the 09. The chain side is similar to the 08 but the brake side is a lot thicker and the marks are on top of the block instead of the side. When adjusting the chain always start counting the marks from the rear, the chain side has less marks due to the front raised portion that holds the axle. Oh ya, get ready to buy a new axle nut wrench, it is now 32mm I believe.

ok, i just got a new 09. rode it once, threw away the stock chain and now im putting new sprockets and a better chain on. i got everything installed but there is a tight spot in the the chain when i spin the wheel. that means its not on straight right??

i dont understand because i have counted the marks on the axle blocks from the back going forward and they line up. and i have also measured the chain adjuster bolts and they are pretty much backed out the the same length (within a mm).

what am i doing wrong? i have been on hondas for a while and never had a problem like this. are there aftermarket axle blocks or something that i could get to make this easier to do?

ok, i just got a new 09. rode it once, threw away the stock chain and now im putting new sprockets and a better chain on. i got everything installed but there is a tight spot in the the chain when i spin the wheel. that means its not on straight right??
Incorrect tension or alignment will not cause this problem.

It is one of 3 things whenever you have a tight spot like this:

  1. The front sprocket is out of round
  2. The rear sprocket is out of round
  3. The chain is binding or is not of a single, consistent pitch

To isolate the specific problem, set the bike on a stand, or if it only happens on the ground, leave it there. Rotate the wheel or roll the bike and watch for the tight spot. Mark the position of the front sprocket, rear sprocket, and chain with anything suitable, and rotate it until the tight spot returns. By looking at your marks, you should be able to tell which one the spot is synchronized with.

If the mark on the rear sprocket is in the same position each time it gets tight, your problem is a defective, or improperly mounted rear sprocket. Likewise with the front. If it's the chain, I would be quite surprised, since you said it was new.

Either way, on any unfamiliar bike, you should always check the accuracy of the axle blocks by doing a more advanced alignment check, and be sure on the '09 that you give it as much slack as the manual calls for. If you think it looks loose, it's probably right:

http://www.thumpertalk.com/forum/showthread.php?p=4584448#post4584448

Incorrect tension or alignment will not cause this problem.

It is one of 3 things whenever you have a tight spot like this:

  1. The front sprocket is out of round
  2. The rear sprocket is out of round
  3. The chain is binding or is not of a single, consistent pitch

To isolate the specific problem, set the bike on a stand, or if it only happens on the ground, leave it there. Rotate the wheel or roll the bike and watch for the tight spot. Mark the position of the front sprocket, rear sprocket, and chain with anything suitable, and rotate it until the tight spot returns. By looking at your marks, you should be able to tell which one the spot is synchronized with.

If the mark on the rear sprocket is in the same position each time it gets tight, your problem is a defective, or improperly mounted rear sprocket. Likewise with the front. If it's the chain, I would be quite surprised, since you said it was new.

Either way, on any unfamiliar bike, you should always check the accuracy of the axle blocks by doing a more advanced alignment check, and be sure on the '09 that you give it as much slack as the manual calls for. If you think it looks loose, it's probably right:

http://www.thumpertalk.com/forum/showthread.php?p=4584448#post4584448

thanks gray, i was hoping you would respond. anyways, i took your advice and marked the front and rear sprocket as well as the chain. it seems the problem lies with the new rear sprocket. the tight spot is consistant with the marks on every rotation.

does that mean the sprocket is ovaled out or that its not mounted flat on the hub? i made sure to do the cris-cross pattern when putting it on

I ran into the same problem on my 08, and I used the measuring techniques found on this forum. But, I recently tried a set of FTD axle blocks. These are just like the zip-ty axle blocks in the sense that they are one piece with the axle adjuster bolts. I have found that their marks perfectly align the rear wheel and do not require measuring in order to get the wheel strait.

With the chain off, you can determine if the sprocket is running flat or round. If it's not flat, it could be something you did. But it would be, it seems to me, difficult to make a mistake that caused the sprocket to be mounted off center, but if you find the sprocket eccentric, then check the ID of the sprocket and/or the OD of the mounting flange on the hub to make sure it isn't out of round. It shouldn't be, unless you ran the chain really tight on your old setup, and bent it landing a jump.

If the hub flange looks good, it's probably a defective sprocket.

its hard to tell if the sprocket is round or not by looking at it.

the OD of the mouting flange is 130mm all the way around so thats not the problem. it must be the sprocket, but i want to have proof before i go return it. do u have a precise way of measuring it? i'm having a hard time finding a spot to take a measuremnt from with the teeth being there.

i also checked the ID of the sprocket and found that it was out of round by .4mm. is that enough to cause my problem?

The mounting flange is round, but is it concentric? Bolt the wheel in and spin it against a fixed reference. Likewise, with the sprocket in place, spin the hub and sight to a fixed point on the swing arm vs. the low point of the valley between teeth.

You should be able to measure with a caliper the distance from the sprocket ID to the low point of several teeth, also.

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