Jump to content

[S] Different chain tension based on the rotation of the rear wheel

Recommended Posts

Hello TT! Today, in an attempt to remedy the chain slap on my DRZ I tightened the chain up a bit. I can't say if that is what caused this because I never did a check of the chain slack with it rotated in different positions before I tightened it.

  It's very likely that the chain has been damaged; I think that it somehow hit one of the bolts that hold the front sprocket chain guard in (breaking the bolt) and then the chain was continuously slapping against the now loosened and out of place chain guard. To prevent further damage, I removed the chain guard until I can get the other half of the bolt out of the threads in the crankcase.

   I have already ordered a new chain but I'm not sure if the inconsistent slack on caused by chain damage or if the rear axle is misaligned. Could the axle being misaligned cause that?

Share this post


Link to post
Share on other sites

its very doubtful contact with a bolt or slap damaged the chain .. what is much more likely to cause chain damage is running it too tight, and then when the suspension is compressed hard while riding it stretches the piss out of a spot or two, loosens your front sprocket and other various unsavory things  ..  chain slap or 'shake' happens at certain speeds more than others when it gets in a rhythm, on at least my DRZ, and ive come to the conclusion its because the sprockets do not align well .. chain tension has nothing to do with it, keeping it well lubed helps ..

  • Like 1

Share this post


Link to post
Share on other sites

My wager would be that your rear sprocket is bent. Axle alignment could cause binding or friction but it would be very obvious because the tire would be up against one side of the swingarm. Also, it would be consistent around the full rotation of the chain/sprockets.

In order for the chain to loosen/tighten during rotation is either a bent sprocket or a stiff spot in the chain.

Replace the chain, both sprockets and case saver IMHO.

  • Like 2

Share this post


Link to post
Share on other sites

Don't know how I didn't catch this before; just went to check out the front sprocket: the nut is loose (I can rotate it back and forth), and the sprocket is loose (moves side to side), also that washer looks pretty bad, is it supposed to be bent like that?

20170704_160905.jpg

Share this post


Link to post
Share on other sites
50 minutes ago, Rebeljah said:

also that washer looks pretty bad, is it supposed to be bent like that?

 

Yes. Its a lock washer. You bend one side flat against the nut so it cant loosen.

Share this post


Link to post
Share on other sites

As a chain wears, you will get some links more worn than others, not nessesarly from any alignment or tension problem. So you will experience tighter and looser spots when rotating the wheel.

  • Like 1

Share this post


Link to post
Share on other sites

Cleaning and lubing the chain may loosen up any tight spots. Find the tightest spot and set your chain clearance there. If the adjustment is good at the tightest spot and still too loose at the loosest, it's probably time to start thinking about a new chain and sprocket set. 

  • Like 1

Share this post


Link to post
Share on other sites
48 minutes ago, brucen said:

Cleaning and lubing the chain may loosen up any tight spots. Find the tightest spot and set your chain clearance there. If the adjustment is good at the tightest spot and still too loose at the loosest, it's probably time to start thinking about a new chain and sprocket set. 

Yep already ordered a new chain, just trying to get it safe to ride until it arrives, I tightened the loose sprocket nut and then loosened the chain.

Share this post


Link to post
Share on other sites
8 hours ago, Rebeljah said:

Yep already ordered a new chain, just trying to get it safe to ride until it arrives, I tightened the loose sprocket nut and then loosened the chain.

Chains and sprockets should be replaced as sets.

  • Like 3

Share this post


Link to post
Share on other sites
13 hours ago, ohiodrz400sm said:

Thank you! Sort of high-level stuff for me to be reading but I think I understand. My sprocket nut was loose so I tightened it which fixed the sprocket wiggling. But should I loosen it back up to prevent warping on the parts underneath? If I'm reading it right it says that the damge is caused by the loose sprocket on the counter shaft? Should I worry about the torque on the nut? Probably time to invest in a torque wrench haha.

Edited by Rebeljah

Share this post


Link to post
Share on other sites
17 hours ago, OhioYJ said:

Chains and sprockets should be replaced as sets.

Yeah going to order a new sprocket set also.

Share this post


Link to post
Share on other sites
Probably time to invest in a torque wrench haha.

Where are you located? The harbor freight 1/2" drive torque wrench is very highly rated against the high end snap-on and Matco units. Its only $20 and I check mine regularly for accuracy with great results. For the hobbiest, I can't recommend it enough.
  • Like 1

Share this post


Link to post
Share on other sites
2 hours ago, Backwoods-Bomber said:


Where are you located? The harbor freight 1/2" drive torque wrench is very highly rated against the high end snap-on and Matco units. Its only $20 and I check mine regularly for accuracy with great results. For the hobbiest, I can't recommend it enough.

I have the HF 1/4" , 3/8" , and 1/2" drive units :)

Edited by 74jimbo
  • Like 1

Share this post


Link to post
Share on other sites
18 hours ago, Backwoods-Bomber said:


Where are you located? The harbor freight 1/2" drive torque wrench is very highly rated against the high end snap-on and Matco units. Its only $20 and I check mine regularly for accuracy with great results. For the hobbiest, I can't recommend it enough.

Not bad! Is it a break-away, or dial type?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

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

Reply with:


×