9.17. Rephase crankshaft

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The following is information on the results of a crank rephase I did on 10/8/05 as a practice run. I've never done this before so anything I may add to this is based on a single rephase experience only. Please consult others on the list for more info before you try this yourself. This crank was rephased to 277 deg using all the original components.

Here are the before and after runout data on centers for my crank. Image:Ctrs.jpg

Crank had 21K miles on it. Bike was abandoned outdoors for at least 5 years in winters with 4 feet of snow or more. Right cylinder had filled with water at least once and was filled with rust from the rings corroding. Bottom end was full of oil and no rust or problems observed.

Here are some runout worksheets for recording runout data as you work on your crank. Each runout area has 4 large boxes for recording the actual runout and a small box next to it to record the highspot on the crank in degrees or number of teeth. A suggestion here is to use the starter ring gear as an indicator of position on the rotor. There are 63 teeth which equates to about 5.7 degrees of rotation. Mark the teeth in 10 tooth increments with a laundry marker or crayon so you can more easily read where the highspot it. Knowing where the highspot is will help you understand what has to be moved to correct the runout. There are 4 places to record runouts at each point so you can more easily see if you are moving in the correct direction. If you need more than one sheet, I suggest you number them so you know where you are if you leave the project for a day or so. Fill in the date for the same reason.

Image:Crank Dim.jpg

Image:Crank RO Ctrs.jpg

Image:Crank RO brgs.jpg

Image:RP worksheet brgs.jpg

Image:RP worksheet ctrs.jpg


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