In vague generalities, how much does distance affect pinion preload? [Archive] - Chevelle Tech

: In vague generalities, how much does distance affect pinion preload?


gibbons
Dec 20th, 09, 1:44 PM
i know, I know, all gears and housings are different. So are bicycle wheels, and I have trued enough of them to know that about 1/8 of a turn on the spoke nipple pulls a rim 1/32" or so laterally. So I am assuming that some of you guys have a gut feel for this.

I don't have the required long wrenches and special yoke holder, so I am going to use shimmed solid spacer with my 150fp torque wrench and mega pipe wrench. If I did my first pass and got, say 8inchpounds of pinion preload torque, how much shimming would be required to get it to a nice 16?

big gear head
Dec 20th, 09, 2:03 PM
A .001 shim change with a solid spacer will make a big difference in bearing preload. If you shim it and get about 18 inch pounds of preload and you want to get to 20 then a .001 shim change will probably put you over your limit. If you change the torque on the pinion nut it will make small changes in the bearing preload. If you get 18 inch pounds of preload and increase the torque on the nut from 150 to 175 foot pounds then you might get the extra 2 inch pounds of preload that you are looking for. I recommend trying for 200 foot pounds of torque on the nut. If you need to make very small adjustments to the bearing preload and you can't get what you need by changing the shims then you can do it with torque changes on the nut. Be sure to use your old pinion nut when setting it up and save the new nut for the fianl assembly.

gibbons
Dec 20th, 09, 2:07 PM
Wow!!! Sounds like this is going to be entertaining. Thanks!

I know that solids/shims seem like the sissy way, but I am kinda constrained to it if I am going to set it up myself.