I just about drive myself crazy each time I tighten my chain. I get the marks lined up perfectly on both sides of the swingarm and then it is ruined by tightening the axle nut. It seems like the tightening of the axle nut levers the axle a bit and throws the mark on the sprocket side off by about 1 mm. I've tried compensating by tightening one side more than the other. I've also tried measuring the adjuster screws' length and making that equal on both sides. There's got to be a better way than fiddling around and doing this ten times to get the marks to look the same on both sides.

Rook

Rook-How's it going? What I do-set the wheel(I use a rear stand)where you want it to be(chainwise,equal at marks on both sides).Don't completely loosen the hub nut.Just enough to move it WITH THE ADJUSTER BOLTS.Adjust the bolt to the mark you need-hold the bolt,and tighten the LOCK NUT SECURELY.Same as the other side.Then tighten the hub nut.It can't possibly move with the adjusting bolt secured.Gotta make sure the axle is firmly against that adjusting bolt.Probably what's happening is you're adjusting the bolt there,but when you go to tighten the lock nut,the bolt is also turning,which will cause the adjustment to change.(you ARE tightening the locknut on the adjuster bolt,yes?)(turning it CLOCKWISE till it is tight?).That's most likely what's going on...............OR......You MAY be looking at your hashmarks/axle mark AT A DIFFERENT ANGLE THINKING IT'S EVEN ON BOTH SIDES?(I've done that).You gotta look straight in at it,not forward or back of the mark lineup.(even looking "off a little" will cause you to NOT have it lined up)Hope that helps

* Last updated by: blue07 on 5/3/2009 @ 12:37 AM *

Rook-How's it going?

Good! I've been facebooking a lot the last couple weeks which has kept me away from the 14ninjaforums. I really need to till the soil in that wasteland my marriage turned my social life into. Not sure there's anything developing but it's fun checking around.

Probably what's happening is you're adjusting the right bolt there,but when you go to tighten the lock nut,the bolt is also turning,which will cause the adjustment to change.

No, I'm using two wrenches - one to hold the adjuster, the other to tighten the locknut. I wondered if having the bike on the side stand didn't have something to do with the shift of alignment. I'll try to tighten the axle nut good and snug up on the rear stand. I imagine forward torqueing should be relatively safe with the rear stand I use. Thanks.

Rook

* Last updated by: Rook on 5/3/2009 @ 12:43 AM *

I don't think adjusting it on the sidestand would hurt anything-EXCEPT.....Making sure the axle's butted up against the adjuster nut might be iffy.I put mine like I said on the rear stand,then after I've loosened the adjuster/lock nut,I give the tire a good bop with my palm to seat it in there before tightening.(you can chock the front wheel with something under there).However-without changing gearing or NEW chain,the adjustments should only be ONE WAY-that's CLOCKWISE on ALL bolts.So loosening the locknut shouldn't be an issue(only retightening it),only the hub nut,that has to be loosened of course(enough to move the wheel) and adjusting the adjuster bolt.You shouldn't ever have to go the other way with your adjustment(looser).

* Last updated by: blue07 on 5/3/2009 @ 1:01 AM *

only the hub nut,that has to be loosened of course(enough to move the wheel)

That was another thing I was thinking could be the problem. I have been loosening the axle nut enough to let it spin freely. That is probabley allowing the axle to "relax" way too much in the swingarm slot. After breaking the axle nut free, about how many turns do you loosen it?

Rook

Do you check the wheel alignment (with string) or rely on the swingarm marks?

Thanks Hub. Those are really good pointers. I got it just about perfect so I'm not going to f withit any more until next time.

Rook

I use one of them Motion Pro jobbies that clamp on the rear gear. It has a 7 in pointer rod that lets you know if the chain is strait so I never worry about the alignment marks. As it turns out they are close enuf to use and not worry about.

Do you check the wheel alignment (with string) or rely on the swingarm marks?

Would somone mind explaining the string method of checking wheel alignment?

I have never seen anybody string a bike for a chain adjustment. It has always been because the bike handled like crap and the string was enuf to confirm bent forks or steering head.

^^Thanks, Hub. Chain adjustment is about the most routine and most important thing we do in the maintenance area but still, I imagine there are a lot of questions about this procedure. We have some really valuable info on this topic. This has cleared up a lot of my chain maintenance quandries. I bemieve your info and that of the others posting here wil help demystify the whole deal for everyone who reads this.

I would agree that the string method would seem to introduce more error than it eliminates. String stretches for one thing. Perhaps a piece of cable would be more accurate. Who knows when the front wheel is dead straight forward? As imperfect as my chain adjustments may have been in the past, I see no unusual ware on my back sprocket. Will be interesting to look at the front sprocket some day soon. If it's worn, I'd love to try a new gearing set up anyway. Sprockets are pretty cheap.

Rook

* Last updated by: Rook on 5/6/2009 @ 8:18 AM *

I wrap teh string around the rear wheel and lie in front of the front wheel. This way I can keep the front wheel straight, put the bike in gear so the rear wheel does not rotate.

So, the rear tyre is wider than the front. While laying in front of the bike and holding each end of the string wide of the bike so that the string only touches the rear of the rear wheel. Now, while watching the rear wheel, move each end of the string closer to the front wheel. Stop when the string touches the front edge of the rear tyre. At this point, the string is aligned with the direction of the rear wheel and projects a line forward. There are no kinks/bends in the string, because it is just barely touching the front edge of the rear tyre.

It is now important to keep the front wheel straight. Maybe a scantily clad member of the opposite gender could be useful here. :) If the rear wheel is properly aligned, the gap between the string and the side of the front tyre will be the same on both sides. The length of the string will exaggerate any misalignment of the rear wheel.

Misalignment affects the handling of the bike, it feels like having low tyre pressures. the bike 'bump-steers', meaning small bumps mid corner tend to momentarily alter the angle of lean; hit a bump and the bike wants to stand up for a split second. I get the same feeling with the 190/50 rear tyre. change to a 190/55 or a 180/55 and the bump-steer goes away.

I recommend this when adjusting the chain as this is the only time the alignment can change. Although once done one, adjusting the chain from that point on should involve the same number of turns on each side of the adjusting bolts (left+right) thereby applying the same adjustment to each end of the axle and maintaining the wheel alignment. This means the string method only needs to be done occasionally, rather than every time the chain is adjusted.

Sorry for the delay in responding, work and family pressures are high at the moment.

I don't believe string lining the rear wheel is a chain issue, the possible misalignment is too small to have an impact on the chain. I believe it is only a handling issue.

Nice pickup Hub, and in your opening question too! "Impressive, Obi-wan!" I must confess that I've had the same thoughts about bump-steer, being up on one side and down on the other, but I've not been able to detect that difference.

I've discovered over time that there are three things that upset the handling resulting in bump steer.
[list=1]
low tyre pressures
wrong tyre profile
misaligned wheels
[/list]

The last can be caused by either the rear wheel being misaligned as a result of chain adjustment, or the front wheel is misaligned due to bent or poorly installed forks. Either way the result is the same, when pointing in the same direction, the two wheels are not on the same front-to-rear axis. When misaligned, the direction of the rear is fixed, so the direction of the front is adjusted (by turning the bars) and the bike goes where the rider wants. If the rear is of-axis then it is sending the bike slightly to the right or left and the front is adjusted accordingly. These are minor measures and mostly imperceptible in a straight line, but I notice them when leaning and they are exaggerated by uneven surfaces mid turn.

Others have mentioned that the ZX handles like a barge when pressures get below 40psi. I agree. The same feeling is induced by a rear profile that is too wide or too flat; it is also induced my misalignment.

I can't describe in words what I mind's eye sees; there needs to be a balance between the vertical forces at play. Weight is pushing down through the centre of of the bike at the same angle as the bike. The ground pushes back through the centre of the contact patch of the two tyres. If the rear contact patch is not aligned with the front then both front and rear will be off centre, where centre is the line described by the centre of gravity and the direction of the bike.

I believe that the imbalance in vertical forces resulting from the misalignment is the reason for the barge like feeling.

When the rear contact patch is too wide (low pressure or wrong profile) the vertical forces on the front are correct and the bike wants to turn-in in response to the riders input, the rear forces are not aligned and the rear resists the lean. The front wants to lean and therefore turn while the rear wants the bike to stand up resulting in that familiar barge feeling.

I find that when I get those 3 elements right, the handling transforms; the wheels are aligned with the vector of the bike (CoG+direction), the vertical forces are balanced and the bike feels like it 'falls' into the corner and needs no further rider input to stay at the chosen lean angle and further, requires the rider to stand it back up again. That's when I think the bike feels balanced.

Hub, I hope I addressed your critique. I enjoy your challenges, keeps me on my toes knowing you are going to review my comments with a ruler and whack me over the knuckles when I dribble some BS. But I don't think I understood you comments about 'lift angle'

Your move...

I wrap teh string around the rear wheel and lie in front of the front wheel. This way I can keep the front wheel straight, put the bike in gear so the rear wheel does not rotate.

So, the rear tyre is wider than the front. While laying in front of the bike and holding each end of the string wide of the bike so that the string only touches the rear of the rear wheel. Now, while watching the rear wheel, move each end of the string closer to the front wheel. Stop when the string touches the front edge of the rear tyre. At this point, the string is aligned with the direction of the rear wheel and projects a line forward. There are no kinks/bends in the string, because it is just barely touching the front edge of the rear tyre.

It is now important to keep the front wheel straight. Maybe a scantily clad member of the opposite gender could be useful here. :) If the rear wheel is properly aligned, the gap between the string and the side of the front tyre will be the same on both sides. The length of the string will exaggerate any misalignment of the rear wheel.

Misalignment affects the handling of the bike, it feels like having low tyre pressures. the bike 'bump-steers', meaning small bumps mid corner tend to momentarily alter the angle of lean; hit a bump and the bike wants to stand up for a split second. I get the same feeling with the 190/50 rear tyre. change to a 190/55 or a 180/55 and the bump-steer goes away.

I recommend this when adjusting the chain as this is the only time the alignment can change. Although once done one, adjusting the chain from that point on should involve the same number of turns on each side of the adjusting bolts (left+right) thereby applying the same adjustment to each end of the axle and maintaining the wheel alignment. This means the string method only needs to be done occasionally, rather than every time the chain is adjusted.

+1 on this, and everything else russty said above..

By the way, How are you doing russty?? How's the riding down under? everything still upside down

These cheap lasers with the little tri-pods, you know like wally world sales. Work real good for a modern string, set a laser on each side of the rear wheel(it helps to have the bike up on a rear paddock stand) shine down beside the front and rear of the rear tire, and the front-wheel should be directly between these two-lines..

get the lasers that make the lines not the little dot..the ones like you use in carpentry.

PS>> it is very important to have the rear wheel strait and true, an untrue rear wheel will effect handling, especially at high speeds and when leaned over,<<<<

Hi Hub!

My take on this is that the bike follows the path of least resistance, so if the rear is a little off axis, i see 2 possibilities.
1. the bike 'drags' the rear wheel so that it scrubs a bit. We are only talking about less than one degree out of alignment.
2. the front wheel turns a little so that the front and rear are pointing in exactly the same direction. In this case both wheels are on different but parallel axes and yes the bike is 'crabbing' slightly, but only slightly. This is not noticeable in a straight line as the two axes might only be offset by 1/4"

My money is on #2 as I think this is the path of least resistance. no tyre dragging, only a slight change in direction through the handle bars.

This assumption (#2) explains the odd handling sensation with bumps mid corner or riding along the seam of the bitumen sealer, or grooves from resurfacing etc when the bike wants to go its own way.

Over the years and many motorcycles I have found that many of the alignment marks on swingarms are WAY off. What has always worked for me is the straight edge or string method to find perfect alignment with the chain loose, then equal tuns on each side from then on - ignore the marks, just keep the turns dead even on each side, making sure that the axle stays fully against the adjusters. On some bikes I have owned this meathod has completly changed the handeling for the better, but to Kawasaki's credit, my ZX-14 was pretty close - not perfect, but a lot closer than some brands.