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[zonggong]

I followed the service manual for adjusting the chain tension ... do the RHS first, hence the cam move from notch 12 to 13, then the LHS, also from 12 to 13. After reading the other thread and checking as best I could with a string it did not seem correct and made further adjustments to the LHS hoping to 'true' the wheels up (cams from 13 to 9 on the LHS). It seems I need a better way to measure confidently so will get some longer straight edges and follow your suggestions and report back.

I find it hard to believe that there would be more than about 1 notch difference, hence my request for advice. Thanks all for your suggestions.

[jefrs]

A big tell is can you take both hands clean off the bars at 45mph and keep them off?



If you have a stay-open throttle widget you should be able to ride the bike no-hands for a considerable distance.

[nigelphoto]

Jeff, if you are an experienced white van driver then not only can you ride at 45mph for considerable distance without your hands on the bars, you should also be able to txt, eat a sandwich and read the Sun at the same time - these are all transferable skills you know.

[jefrs]

nigelphoto, I seem to remember the, "eat lunch and read the newspaper" as a Murray Walker comment on the back straight of some F1 circuit.



But yeah, if your bike falls over to the side and you have to grab the bars back, you have an alignment issue.

[ric]

"NOTE : The above procedure is to be adopted to achieve correct wheel alignment and to compensate for pin dimension tolerance on the swing arm. The procedure referred to is the adjusting of the cams to align the wheels. Could the 'notch' difference be the result of pin dimension tolerance?"


The latest and larger silver finish snail cams have been changed to remove this anomaly. The older yellow passivated snail cams had the hole centres in the same place so the difference in diameter between the long axle and short one did indeed require taking into account resulting in unequal notch numbers when the wheel were in alignment. From memory there is a 4 notch difference.
However on the larger/later cams the smaller hole for the long axle has been moved closer to the leading edge so theoretically the numbers should be the same.
axle stands work very well to get a pair of straight edges higher up the wheel for greater accuracy - make sure the rim welds are out of the way (both @ 12 o'cloc0k before starting the alignment check.

[zonggong]

I put the bike up on axle stands as recommended and placed a straight edge on each side of the rear wheel about 180 mm up from the tyre circumference and lightly clamped them in place. The straight edges extended well past the front tyre (2400mm long) and fitted just under the front disc. The wheel rim welds were at 12 O'clock. I adjusted the LHS cam up and down to see then effect and finally set it where the straight edges on both sides left min clearance with the front tyre (the back tyre is 91mm width and the from 84mm). I then checked this on both sides using the string method and was satisfied it seemed correct. I did this with the axle nuts nipped up to avoid any changes when I tightened everything up and went for a ride. It seemed to go well and possibly better than previously, however, using the hands off test, did seem to drift a little to the right. I then adjusted the LHS cam by 1 notch higher, to try and counter the right drift, and took it for another run. The drift to the right was about the same. That is where I am up to with the RHS cam set at 13 and the LHS cam set at 9. Nothing looks out of shape with the front forks - the wheel looks to be in alignment with the downtube. The snail cams match Ric's description of the more recent ones ... looks like they are zinc plated.
I'd appreciate any other suggestions or comments on my method.

[jefrs]

ric - I believe the discrepancy to be tolerance on both swinging arm and frame build, and on the steering head and front forks too. If you lay one (C5) snail cam on the other they are identical, they're not handed. I feel the urge to re-do mine as although it goes well no-hands there is a very slight left/right on power and braking. There again it is an RE not a fine-tuned racing machine (fwiw those can be a real nightmare). It won't happen soon, we are currently enjoying a burst water supply pipe.

[jefrs]

zonggong - the drift left or drift right thing can be counter-intuitive. We automatically counteract lean by shifting our weight. Try setting the LHS one notch the 'wrong' way to check if you're moving the cam the 'right' way. Be careful, with it out of alignment the bike can kite over 20° on you. Obviously one side is set on the chain and the other to align.



With the spindle loose we adjust the brake plate (both nuts) with the weight of the wheel off the bike and on the floor, so the brake plate will drop to the bottom of the fork slot, when we tighten the spindle the weight of the wheel comes back onto the bike so that side tends to be at the top of the fork slot i.e. the bottom of the tyre may be a little further to the left than it should be all else being equal. I like to tighten both brake plate nuts and the spindle whilst putting my weight onto the pillion so they're both pushed to the top of the slot as I tighten them. Then eyeball the wheel for vertical. It doesn't take much vertical movement to throw the alignment out.



And then we have to work with what we have. I don't have a pit stand, I do have a big spirit level which I put on both sides and eyeball the gap. The cams can only go by one notch at a time and that is visually recognisable at the front. And then ride it.

[ric]

So you have the snail cams which if everything on the bike was assembled absolutely perfectly (including the stubs they locate against) they would both sit on the same notch to provide correct wheel alignment...
Stupid question but were you riding on the right hand side of a cambered road during your test ride?

It took me a long time to sort my alignment issues out, just needs perseverance until you know its right, not just think it's right.
When you do get it spot on, the steering becomes noticeably lighter and needs a lot less input.



Make sure the front end is actually 100% before trying to sort out the rear! If perhaps you found you couldn't get an identical reading of all four measurement points on the front tyre using hard straight edges, it means your wheel is either offset between the forks or if it is central then it the rear wheel isn't and the spokes might be in need of some tweaking to move the rim across.

Unlikely but possible, you could have a bent steering stem which will throw the wheel off to one side and cause handling/alignment problems. After removal of the stem nut can you look down the centre of the stem and see the middle of the front tread pattern?



Are the handlebars and wheel spindle parallel? - Brake firmly using only the front brake whilst travelling in a straight line. If the handlebars twist slightly to one side as the forks compress - but the bike continues heading in the same direction then they are not parallel.



Despite moving the rim weld out of the way when using straight edges, did you unknowingly place them against a part of the tyre which was not correctly seated on the rim or where the rim was slightly buckled thus throwing the straight edges off to one side so the wheels only seemed aligned?

[Nettshubby]

Just a thought, but have you got both cams on the same way round? ie, so that the straight edge is facing the same way on both sides?