Sprocket alignment

I am in the middle of swapping out the stock swingarm on my 1994 Kz1000P, with a ZX636 swingarm. I am now at the point of aligning the chain to the front and rear sprockets. I've done some surfing on this forum for tips on chain alignment. I found a post that suggested running a string from sprocket to sprocket for alignment. I went out to my garage and, thought out the string process.

I then realized that I have this simple Black & Decker laser that I bought to hang vertical blinds. I think I paid less than $20.00 for the laser.
Long story short, I placed the magnetic laser on the rear sprocket and aligned the two sprockets, spot-on. It worked so well that I found myself going through the process a few times to confirm alignment. i' m sold on the laser guided alignment. Hope this comes in handy for anyone else tackling an alignment of the chain.

So is the back wheel centered ? Does it line up with the front wheel ??

Although it may at first seem counter-intuitive, many new motorcycles, especially those with fat rear tires, are designed with the rear tire center-line being offset from the front tire center-line.
When upright and rolling straight ahead, the center-line of the rear tire does not exactly match the center-line of the front tire.
The tire center-lines are parallel, but don't overlap.
Correct tire alignment requires both tire center-lines being parallel when the bike is rolling upright and straight forward. The wheels are in parallel planes. But not necessarily in the same parallel plane.

Correct sprocket alignment requires both sprockets being in the same parallel plane (regardless of the bike's position).
Being in the same parallel plane assures that the chain has a straight pull between the sprockets, irrespective of the bike's orientation.

Forcing the rear wheel into the same parallel plane as the front wheel in order to achieve matching tire center-lines may create mis-aligned sprockets.








See following links for more info:

www.motorcyclemetal.com/downloads/Harley...%20Made%20Simple.pdf

xlforum.net/vbportal/forums/archive/index.php/t-1600964.html


Good Fortune!

What Patton says about parallel planes, but not necessarily the same plane, grates on my sensibilities, but seems to be true. The ZRX1200 and several models from BMW and HD come from the factory with rear wheel offset as big as 25 mm.

www.zrxoa.org/forums/showthread.php?2755...ghlight=Wheel+offset

However, at least one rider in that thread claims to be able to feel the effect of the offset when cornering hard.

The wheels are aligned, and the tire center-lines are parallel. Rear wheel centered with factory spacers. That was the first thing I did. I then went from that point and aligned the sprockets. Don't know why I was so thrilled to see that my laser idea worked so well but, I must admit......it was exciting to go from an idea to completion.

Thank you ALL for the great feedback and invaluable information. I keep telling my wife that this forum is my "facebook".

It is nice to know that the little tool can be used for mor manly projects, too. :woohoo:

So youre saying that the back wheel is off center? Its parallel to the front wheel. How much is it off by?

Tks for a great idea.
It will come in handy when I start with my project after the season is to it's end when I will try to fit a Zephyr 750 swingarn and a ZXR 400 wheel to my Gpz750 -82

I don't like it. I would do a off set sprocket like the GOOD builds do here.
Steve

swest wrote: I don't like it. I would do a off set sprocket like the GOOD builds do here.
Steve

Me too. Im shocked to hear that BMW do it (and not at all surprised that Harley do it.) Having any manufacturer do it,youve got to think that theyve spent a lot of time and money on the geometry of the bike as a whole and setting it up safely and properly. Thats very different to
sticking an odd wheel in the back of your bike and shoving it over to the side to get the chain line to run right.

P.S. While Im at it,whats your plan for the front end are you changing that as well? What rear tyre are you trying to fit? I seem to remember from an earlier post you mentioned a 180,or was that someone else?

When fitting a shouldered (i.e., offset) counter-shaft sprocket -- to position the sprocket outward for alignment with the rear sprocket -- sufficient clearance for the drive chain may be a consideration.

Also, there's a limit to the amount of offset that can be safely used without a nose added to the sprocket to support its port side.
The nose fits into a bearing support plate that replaces the stock sprocket cover.

kzrider.com/forum/2-engine/219130-offset...l=component&type=raw

www.dgchassis.net/outer%20bearing%20supp...bearing-support.aspx

To help avoid the issues of chain clearance and prospective need for a support plate, some folks may prefer to reposition the rear wheel in order to align the rear sprocket with the stock counter-shaft sprocket.

Good Fortune!

Thank you all for your positive and neutral feedback. So, I've been measuring and also guiding the rear wheel (no tire)....to the front wheel/tire with my laser tool, as well as lots of double checking. I've used the center of the rear wheel to get an idea of where I am with wheel alignments, front to rear. I am still waiting for the rear tire to be shipped to me, tire size 180. I've also run a centered tape line on my service lift, front to back to facilitate alignment......making sure bike is centered on lift as well.

So, I think I will wait until I have mounted the rear tire before wasting any more time playing around with alignment. Once I have the tire mounted, I will then dial in the alignment.

I agree with you guys. I do NOT like the idea of the offset wheels. Hard to believe that the manufacturers would go through so much research and development AND tons of money invested in R/D to produce a motorcycle with offset wheels. I wonder if the professional racers feel the effects of the offset? Scary thought!!!

I will plan for a front end upgrade sometime down the road, not sure which front end I would consider. Not to bring anyone down but, My wife and I just found out that she has terminal cancer. I will more than likely take a break from wrenching on the bike, while we get through this. I truly THANK all of you for your guidance and support.

Daniel