Bicycle Mechanics - Shimano 7801-sl hub race

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




View Full Version : Shimano 7801-sl hub race


brians647
01-06-08, 10:24 AM
I just read a relatively new thread that seemed to address my issue here:

http://www.bikeforums.net/showthread.php?t=376469

but i wanted to make sure that the hub issues were the same.

I've got a 7800 rear hub that has scoring on both the outer cone and inner hub races. Is the inner hub race replaceable? Or do I need an entirely new hub? Just curious as the above thread adresses a mountain hub and mine is obviously for the road.

Thanks in advance!


HillRider
01-06-08, 11:00 AM
AFAIK, Shimani hubs do not have replacable inner races. The cone can be replaced but the inner race is fixed in place.

BTW. are you sure the races are really scored and you are not seeing just the ball track? There will be a brighter ring where the balls circulate on both the cone and the inner race and this is normal and perfectly fine. A damaged hub has pits or obvious scratches and damage to the cone and/or inner race.

brians647
01-06-08, 11:07 AM
AFAIK, Shimani hubs do not have replacable inner races. The cone can be replaced but the inner race is fixed in place.

BTW. are you sure the races are really scored and you are not seeing just the ball track? There will be a brighter ring where the balls circulate on both the cone and the inner race and this is normal and perfectly fine. A damaged hub has pits or obvious scratches and damage to the cone and/or inner race.

Yeah, I'm pretty sure. I looked into the problem when the hub began to feel like crap (rough). sure enough, the races are darker in the middle where the balls wore them in (scoring, I believe).


HillRider
01-06-08, 11:09 AM
Yeah, I'm pretty sure. I looked into the problem when the hub began to feel like crap (rough). sure enough, the races are darker in the middle where the balls wore them in (scoring, I believe).

Darker won't matter unless the surface is rough and/or pitted.

Nessism
01-06-08, 11:17 AM
Sounds like the cone was too tight. Unless there is deep pitting or a deep groove, I suggest installing new balls and putting the wheel back into service. When adjusting the cones you want them a little loose off the frame because the clearance will go away when the quick release is clamped down. The groove is not a good thing per say but the wheel will roll just fine anyway in my experience.

Good luck.

brians647
01-06-08, 02:32 PM
Thanks all.

Yeah, by darker I was referring to it being a rough groove. You can clearly feel it when you run your finger nail across it. You can clearly feel the roughness in the frame when the wheel is rolling too. I suspect that the cones were too tight as well. Next time I'll check before riding new Shimano's.

Waterrockets actually warned me about that once, and I only checked the front. Of course, Murphys law dictated the rear to be screwed up.

HillRider
01-06-08, 02:37 PM
Next time I'll check before riding new Shimano's.
Check them all of any make. I built up a new bike with Campy Chorus a couple of years ago and both of the Campy hubs were too tight when I got them.