Cartridge bearing replacement options for 7901
 

Hi,

I have a Surly New Hub with a blown cartridge bearing (snap, crakle *and* pop). The Surly docs spec a 7901 cartridge (12mm x 24mm x 6mm) as replacement bearings for all the Surly New Hubs.

The 6901 or Phil Wood PW901 are available with the same dimensions. Are they adequate replacements for short term or long term use?

I would like to ride tomorrow and I'm certain I can find a 6901 locally. Today I hit up a few shops looking for the 7901 but came home empty handed.

Tonight I looked at the Enduro spec sheet for their 7901 offering and I could not glean any information as to what makes the 7901 different than the 6901 other than a note next to the description of the 7xxx series stating

I found this thread, http://www.bikeforums.net/showthread.php?t=95774 regarding a swap of a 7901 for a PW901 (I assume this is the phil woods 6901 analog) but nothing else regarding the 6901/7901 differences on bikeforums.net or google showed up.

Of course I could ask Surly, Enduro or Phil Wood but it's the weekend...

Thoughts or experience with this?

Thanks much.

More information...

I found more information regarding the Enduro Max 6901 and 7901 bearings at www.bikeparts.com.

One difference is that the installation of the 7901 appears to be directional with an inner (black seal) and outer side (blue seal). The Surly docs say the black side of the 7901 goes out.

Playing the part of junior mechanical engineer I am going to guess the 7901 directional install may have something to do with different radial vs. axial load handling on each side of the bearing.

It appears the 6901 would work in the short term. I guess the risk is lower than expected service life.

If only I would have found that page... in 2008. :)

Properly adjusted and maintained they should last longer than radial bearings. I am not impressed with Phil's stuff.