Wearyeyed
Junior Member
Today I cleaned and lubed my chain, and I remembered a little detail I had noticed last month...
I used a modified "string method" of aligning the thrust-line (rear wheel to front wheel), basically taking one of those construction laser levels that can shoot either a horizontal of vertical line, and is self-leveling internally.
Using a bucket to set the device about 3' from the rear of the bike, and situating it such that the beam *just* kisses the rear and leading edges of the rear tire projecting towards the front, I get a nice laser line on the floor and the wall in front of the bike.
Taking a measurement (I used a vernier caliper, to *really* split atoms along side my laser) from the edge of the front tire at approximately the point corresponding to the center of the contact patch to the laser-line (it shows-up nicely when cast upon the caliper), I adjusted the rear wheel until both sides were equal.
In thousandths...
ANYWAY, prior to the alignment, and after, I noticed the chain rides on the sprocket such that the sprocket is biased toward the inboard part of the chain.
I've checked this on the stand, after long rides, after short rides, cold, hot, standing on my head, etc., and it clearly does NOT want to ride on the center of the rollers.
There IS a tiny gap remaining; it's not jammed-up against the inboard links, but it is clearly off-center.
So, here's the question...is this a "problem" and if so, what can be done about it?
Adjusting the rear wheel to coax the chain to the center is not a perfect solution; over the width of the sprocket I am simply splitting the distance, leaving the sprocket not parallel to the front sprocket, and the thrust-line will be inevitably off.
So, the way I see it, it's shims or shut-the-heck-up and just ride it...
What say you?
I used a modified "string method" of aligning the thrust-line (rear wheel to front wheel), basically taking one of those construction laser levels that can shoot either a horizontal of vertical line, and is self-leveling internally.
Using a bucket to set the device about 3' from the rear of the bike, and situating it such that the beam *just* kisses the rear and leading edges of the rear tire projecting towards the front, I get a nice laser line on the floor and the wall in front of the bike.
Taking a measurement (I used a vernier caliper, to *really* split atoms along side my laser) from the edge of the front tire at approximately the point corresponding to the center of the contact patch to the laser-line (it shows-up nicely when cast upon the caliper), I adjusted the rear wheel until both sides were equal.
In thousandths...
ANYWAY, prior to the alignment, and after, I noticed the chain rides on the sprocket such that the sprocket is biased toward the inboard part of the chain.
I've checked this on the stand, after long rides, after short rides, cold, hot, standing on my head, etc., and it clearly does NOT want to ride on the center of the rollers.
There IS a tiny gap remaining; it's not jammed-up against the inboard links, but it is clearly off-center.
So, here's the question...is this a "problem" and if so, what can be done about it?
Adjusting the rear wheel to coax the chain to the center is not a perfect solution; over the width of the sprocket I am simply splitting the distance, leaving the sprocket not parallel to the front sprocket, and the thrust-line will be inevitably off.
So, the way I see it, it's shims or shut-the-heck-up and just ride it...
What say you?