Chain adjustment margin of error

If you had your chain perfectly adjusted, how much margin of error would there be in either direction with the axle adjustment?

In other words, if you could move the rear axle x amount in either direction without chain slap or chatter, what is x?

Margin of error? I don't follow. What are you trying to figure out?

The axle position can vary for many reasons. Chains stretch. People change gearing.

Watch the video in first post of this thread. <-- click me


On a bike with 10 inches of suspension travel you will have chain slap at some point.


What's worse (IMHO) is a chain that's too tight.


There's a bunch of threads here on chain adjustment.

Where the axle lies is based on getting chain adjustment right, but there's other considerations.

When cutting my brand new chain to length, to go on brand new sprockets, I wanted axle in center of adjustment slot.
Is that what you're asking? Where in the slot you want your axle when everything is brand new?

Sounds like he's asking how closely the axle should lign-up with the adjustment marks on each side, and how far off from each other they can be before bad things happen.

Myself, I put reasonable effort into getting them set at the same position, but I stop at getting the micrometer out.
I believe it's important to take another look at the positions after you tighten the axle nut to make sure nothing has moved too much, and to snug-up the adjuster bolts and lock nuts after the axle nut is tight.

Keep in mind that the torque of tightening the axle nut will slightly twist the adjuster blocks (the things the axle goes through and have adjustment marks on them) as they sit in the swingarm since there is a bit of slop and they can rotate slightly.

The plan:
https://wr250rforum.forumotion.com/t6770-wrx-r-quick-conversion-plans

In a nut shell, I want to change out X and R wheels without major adjustments to the chain. The plan I came up with will result in the sprockets moving .14" from each other between the two applications (SM or DS). If one set-up is .07" too loose (measured from the axle adjustments), and the other set-up is .07" too tight, would I need to adjust the chain much if at all?

If I were bothering to remove a wheel and put another one in place, I'd simply adjust the chain slack if needed.
I certainly wouldn't run the chain slack too tight.

To tight is not good. Puts pressure on the front shaft, chain etc.

If you make it so the axle blocks could be flipped it would work. Either shim them or file them so the difference is right dependent on what set of wheels you are running. This is my plan when I get a set of SM rims. Chances are I will still need to fine tune though.

Otherwise you should just take the time to adjust it, only 5min.