1992 Shimano 105 7 speed free hub swap to 8/9/10 speed free hub and other questions
What specific 8/9/10 speed free hubs are compatible with my 1992 7 speed 105 hub?
After doing some google/bikeforum searches this is what I think I have so far:
- there are compatible free hubs that can be swapped out pretty easily
- the 8/9/10 free hub is wider to the original 7 speed free hub.
- there will be a need to "re-dish" the wheel after the swap to the new hub
- there will be a need to respace the frame from 126mm to 130mm (or even 135mm) accommodate the new wider hub/freehub
I've got an exciting new bike coming in: a 1992 Bridgestone XO-1 it actually has 26" wheels. Its the model with the side pull brakes and 7 speed 105 drive train (as opposed to the more popular 1993 orange framed version which had cantilever brakes and 8 speed drive train).
I did see that you can fit 650c wheels onto this frame even with the normal caliper brakes. http://www.xo-1.org/2010/12/for-sale...xo-1-55cm.html
So I'm more inclined to just re-space the frame to 130mm, keep the original wheels (and modify them with new 8/9/10 speed free hubs) so I have the option to put large tires on them. Then buy another set of 650c road wheels for use in a fast road bike set up.
Any 8/9/10-speed Shimano freehub body will replace the 7-speed on your 105 hub. You may need to obtain the cones and seals that match the new body as your 105 parts may not mate up and form a proper seal.
As you discovered, the 8-speed body is wider but you can probably keep your current 7-speed axle (137 mm long, 126 mm OLD) and won't have to replace it with a true 8+-speed axle (141 mm, 130 mm OLD). The normal axle protrusion past the locknuts is 5.5 mm per side but respacing your axle will still leave 3.5 mm per side and that's enough. You will probably have to redish the rim slightly
Check your frame's actual dropout spacing before cold setting anything as it might be 128 mm and will accept either 126 or 130 mm hubs easily. By 1992, 128 mm spacing was common as the same frame was often sold with both 7 and 8-speed components. My 1992 Trek 1420 was spaced 128 and it wasn't unusual.