From: Lehanover@aol.com
Message-ID: <1e0.f0e9e61.2c7ea0ac@aol.com>
Date: Wed, 27 Aug 2003 20:02:52 EDT
Subject: Re: [FlyRotary] roller bearings
To: flyrotary@lancaironline.net
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In a message dated 8/27/2003 7:24:28 PM Eastern Daylight Time, 
n3773@comcast.net writes:

> Tom Green of Vans tells me that the main gear roller bearings like to be
>  tight, that I could even run 4-6 in/lbs of torque on the nut.  He says they
>  are different from ball bearings.  I have never heard such a thing and
>  wondered what is the general consensus on this. My outside bearing races
>  have worn after 1000 hrs.  I always tightened then and then backed the nut
>  off one face before cottering.
>  Kevin Lane  Portland, OR
>  e-mail-> n3773@comcast.net
>  web-> http://home.comcast.net/~n3773
>  (browse w/ internet explorer)
>  
>  That is correct. Tapered roller bearings can be damaged if run a bit 
loose. They have preload figures for each size. The race car bearings are quite 
large, and I tighten them to 3 foot pounds. I have never had a bearing failure. 
These bearings have a system that allows for any preload and a positive lock 
using two lock nuts. 
You would always want the bearings loaded, so the wheel would track as rigged.

After servicing a bearing, I reinstall it and torque the adjusting nut to 20 
foot pounds.
For smaller bearings, use less torque. This assures that the new races are 
seated firmly in their wells. Then I turn the hub over a few times. Then loosen 
the adjusting nut until the bearing set shows obvious play. Then tighten the 
adjusting to whatever torque for your specification.

 If the nut is not in a position to install a cotter, think about a shim 
washer between the adjusting nut and the "wear washer" between the nut and the 
bearing race. Install a washer that will allow the correct torque and a cotter 
installation. Only the hard "wear washer" against the inner race. The inner 
races "walk" around the shaft all of the time. A thin shim washer will wear away. 
The wear washer is usually pinned or keyed to the shaft, so it cannot turn. 
Otherwise it would be trying to loosen the adjusting nut all of the time. 
Another trick, is to buy a collection of nuts. The threads will seldom have 
identical starts, so one, or another will come out just right over the cotter hole.

Lynn E. Hanover