Re: Bearing Help

[Buccaneer]

I have been studying up on the needed needle bearings for the Firestone.
Trying to replace the old Torrington bearings,
B-108X
BH-812X
The GB-108 and GBH-812 Koyo bearings I was steered to, are .002 to .003 too
small in the OD, and too loose on the shafts as well.
Never did find out for sure what the "X" suffix meant 65 years ago, but
evidently not "precision ground" as the G prefix series Koyo bearings.
Did find a handy Torrington Prefix and Suffix chart at……

http://www.ahrinternational.com/TORRING … ture.shtml

Interesting enough, they don’t have a "X" suffix in the list.
Some of the data says…..
G = Precision Ground
B = Regular Series, Inch Dimension
BH = Large Roller Series, Inch Dimension

From what I’m understanding, "Precision Ground" means your bearings
are going to have a larger ID, and smaller OD.

Interesting also, Amazon gives the same dimensions for Regular
and Precision ground bearings 🙁

I can see wanting the needles precision ground for hi rev shafts, but
couldn’t they make them so they’re standard size after they’re ground?
And why would the shell have to end up under size?

Tried looking on the KOYO site for actual bearing dimensions, found a
large PDF file, but my browser didn’t like it, and rolled over and died.

Think I’m going to order the standard bearings and hope for the best,
and try to sell the G series that are too loose.
Live and Learn.
Buccaneer

Prepare to be boarded!