Bicycle Mechanics - changing chain wheels

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View Full Version : changing chain wheels


kendall
10-25-06, 04:59 PM
built a bike a couple years ago, used triple chain wheels, I'm almost exclusively on the big wheel, never use the small wheel, and have only used the middle wheel maybe three times last year, switched over to a two wheel setup with shorter cranks (170 from 175) on it about midway through the summer, primarily because the 175's felt too 'wide', I was always moving my feet in to get more comfortable and rubbing the cranks.
Been thinking of pulling the small wheel, and hopefully getting the large wheel positioned so it's perfect for the second or possibly third smallest cog, (most riding is there, only time I go below the third wheel is going up the hill on 68'th st from the river in alaske mi, very long and steep, then I wish I could swap the cogs and wheels)

anyone know of anyway to change the position of the wheel, or should I look for a different crank assembly? this one right now is almost a straight line to the smallest cog, and going below the 4th starts messing with the chain line, my goal is to be able to use the larger cogs when/if I need them, but keep it pretty much optimized for my normal riding gears.
yeah I know, kind of stupid like that, I ride it as a single speed most of the time, but I'm not a spinner.

Ken


Matt Gaunt
10-25-06, 05:09 PM
Depending on which BB style you have, you could be limited here. If the BB is a sealed unit 'old style' affair then you can buy different length spindles in the same diameter fit. If you have outboard 'new style' bearings on your BB then this is the standard width and cannot be changed. I hope this is what you meant and I haven't completely missed the point! It's been known to happen!

operator
10-25-06, 06:22 PM
If the chainline is wrong you fix that by getting a new BB with the correct spindle length. Otherwise what is going on with that bike...


kendall
10-26-06, 02:57 PM
Was afraid of that, most of the cranks I tried curved outward from the spindle, and by the time they reached the pedals were too wide for me, the only straight cranks I have are on a lambert.

right now I have the narrowest spindle I could find locally, may have to fire up the mill and lathe and get creative, see if I can mod the lambert cranks or spindle to make them fit my daily. (besides, the Lambert has a sweet looking chainwheel)

Ken.