rear wheel alignment question

[NZDeano]

On my bike - wire wheeled 03 - the markers/notches on the eccentric adjuster do not line up evenly on each side. If I stick a hex key in each side at the same time they are in slightly different positions.
A couple of questions:
Is this normal/OK? (I am picking they should be exactly the same)
Also should each side be able to be moved individually. Mine dont and they both move together. This makes me think it will be altering the wheel alignment as I imagine that by moving them individually is how you actually alter the alignment.
After a 1,200km ride I pulled in to a service station and an elderly gentleman approached me and said he had been following me for awhile and noticed that my rear wheel was out of align. He said it would be affecting the bike when leaning right (it had)
He was right. Then I also noticed that the axle was on the lower setting. This had actually happened because about two months ago I was showing a mate how it actually worked and then we got distracted doing other stuff and I forgot to put it back. So consequently because the back was lower and because the front forks hadnt been dropped up through the clamps she was riding high in the front which was also affecting the steering. So I swung it back up to the correct position and on the final leg of the journey it handled like it should. The weird thing is that once back in the correct position it seemed to re-align the wheel. Now I am trying to figure out how raising or lowering the rear wheel could do this. Could it be something to do with the difference between each side (mentioned above) adjuster and somehow by lowering it accentuated this further?
Any advice appreciated.

[iansoady]

I wouldn't trust the markings myself.

I made sure the wheels were aligned by using the time honoured long straightedge method (with the spindle slackened of course) then, when I was satisfied it was spot on and the chain was properly adjusted, made a centre pop mark on each side to coincide with the marking on the eccentric (I have the eccentrics "upside down"). As the chain rarely if ever needs adjustment I'm happy with this.

BTW a lot of people seem to make the error of slackening off the spindle when they adjust the chain. This is not only unnecessary, it leads to exactly the problem you describe.

[SilverTiger]

Hi Ian.  Just wondering exactly what you mean by your statement regarding slackening of the spindle being unnecessary.  Do you mean loosening the spindle nut is unnecessary?  I don't see how the chain could be adjusted if the spindle nut wasn't loosened.
Cheers

Ian

[Chris Canning]

Why would you want to undo the spindle nut!!! it has nothing to do with it,just undo the 2 pinchbolts that hold the ajusters put an allen key which ever side floats your boat and ajust.

[iansoady]

^^^^^

What he said.

The eccentrics turn together with the spindle.

[SilverTiger]

Ah, gotcha.  I'd forgotten that we were talking about an earlier model with eccentric adjusters.  Mine's an '06 with the later method of adjustment.  Sorry for the confusion 

[PeteH]

Why would you want to undo the spindle nut!!! it has nothing to do with it,just undo the 2 pinchbolts that hold the ajusters put an allen key which ever side floats your boat and ajust.

Mine needs the spindle slackened a tad, have checked everthing else and all seems in order..even the caliper tie bar moves freely... but the adjusters wont move without a slack spindle.

[Chris Canning]

The way it is designed there's no need to undo the spindle,so clearly there's something wrong somewhere.

[JTT]

The way it is designed there's no need to undo the spindle,so clearly there's something wrong somewhere.

Chris is right, something is wrong if you can't rotate the adjusters without slackening the spindle.  That is what is so great about the cam adjusters, once set, the alignment will never change, no matter how often I adjust the chain, and the marks are really irrelevant for this reason.

[NZDeano]

Thanks for all replies. Please pardon my ignorance here, but when you say 'spindle' are you meaning 'axle'
Here's what my manual says for drive chain adjustment:
1. Slacken the chain adjuster clamp bolt.
2. Insert allen wrenches into both hexagonal holes in the eccentric adjusters. Turn the adjusters EQUALLY forwards or rearwards until the chain is correctly adjusted
3.Tighten the chain adjuster clamp bolts to 35Nm.

As mentioned I did all of above without slackening or touching the spindle at all. After clamp bolts were loosened the entire eccentric is free to turn which obviously revolves around the spindle and tightens/slackens chain as well as raising or lowering axle relative to swing arm.
Going by the above workshop manual procedure it says 'turn adjusters equally' which is where my problem is and my question arises. There is no seperate movement between either side. They do not adjust independantly from each other, so you could essentially just use one wrench on either side. And as mentioned the marks on each side are out of align.

I wouldn't trust the markings myself.

I made sure the wheels were aligned by using the time honoured long straightedge method (with the spindle slackened of course) then, when I was satisfied it was spot on and the chain was properly adjusted, made a centre pop mark on each side to coincide with the marking on the eccentric (I have the eccentrics "upside down"). As the chain rarely if ever needs adjustment I'm happy with this.

BTW a lot of people seem to make the error of slackening off the spindle when they adjust the chain. This is not only unnecessary, it leads to exactly the problem you describe.

So Ian, if I cant turn either side independently how do I line up the rear wheel using the straight edge method. On previous bikes you could just adjust one side to bring it in to line.
If I slacken off the spindle, will the allow each side to turn seperately and allow me to align the rear wheel?
Again please pardon my ignorance.

[PeteH]

If I slacken off the spindle, will the allow each side to turn seperately and allow me to align the rear wheel?

Yes... just dont slacken off too much or the lot goes wibbly wobbly....

[iansoady]

After clamp bolts were loosened the entire eccentric is free to turn which obviously revolves around the spindle and tightens/slackens chain as well as raising or lowering axle relative to swing arm.

Not quite - the spindle (axle to some people) stays fixed to the eccentrics. The eccentrics rotate in the swinging arm (which may be what you meant) taking the spindle with them.

Going by the above workshop manual procedure it says 'turn adjusters equally' which is where my problem is and my question arises. There is no seperate movement between either side. They do not adjust independantly from each other, so you could essentially just use one wrench on either side.

Yes, but unless the eccentrics are very free to turn, you're putting quite a high torsional load on the eccentric / spindle / spacer interfaces and you just might get some slippage.

So Ian, if I cant turn either side independently how do I line up the rear wheel using the straight edge method. On previous bikes you could just adjust one side to bring it in to line.
If I slacken off the spindle, will the allow each side to turn seperately and allow me to align the rear wheel?

Yes indeed.

Again please pardon my ignorance.

Better to admit it. We've all been there. I'm currently tussling with porting a little application from VBA to Java (first time I've used it). Have Java's designers never heard of structured programming? And who on earth went for that incredibly strong data typing which is a real pain!