Bottom Bracket Question
 

Hi all,

New member, but been lurking for some time. Great site. :thumb:

I need to replace my original cup and cone BB with a newer unit. I decided to go with a shimano UN55 cartridge unit. My LBS who I've been dealing with for about 40yrs went out of business about 6 months ago and so I've not only lost that but also the valuable advice I could get from the mechanics there. There's another bike shop in the area, relatively new, and the only one for about a 200 mile radius.

My bike requires a 68 X 122 BB, the only one's they stock are 73 X 122. The mechanic there said all I need to do to use the larger BB is install it with a spacer, says they do it all the time. I was worried about the chain line but I bought the unit and installed it and don't seem to have any issues after some minor adjustment of the FD. I'm concerned about there being less of the cartridge actually in the shell. I've gone about 15 miles on a test drive and everything seems fine. Dead of winter here now, -10C today so it may be another month before I can do any serious riding.

My question is , was I given good advice and will I have any issues with this installation down the road?

thanks guys
charlie

there is a 122 UN 55 in both 73 and 68 wide ask the shop to order the part you need.


that was a current inventory level, and they can get one for you no problem..
did you ask them?

i wouldn't worry about the spacer causing structural problems. i've used spacers on BBs from time to time and didn't even think about it causing problems, and it didn't. as long as you are having no chainline problems and it's already installed and working. i say, ... f'gitaboutit. :)

Speaking of spacers. I just installed my new Force group following the directions which tells you to use both spacers, however I am starting to think, Maybe I shouldn't have. How do you know if you are supposed to use the spacers. I am using Sram GXP Force bottom bracket. My frame is standard 68x110

Several types of bottom brackets are made for 73 mm bb shells and include spacers to allow their use on 68 mm shells. This is done to simplify inventory and causes no problems since they are intended to be used that way.

Ok good. So It shouldn't be a problem then. Everything seems ok. Just never remembers dealing with spacers on the BB before.

Hey guys, thanks for the replies. I have obtained the proper size BB online. I won't be returning the larger one because the LBS threw in a few other things I needed for free, like the installation tool. I didn't hear anyone saying it couldn't work so I'm gonna continue to run it and see what happens. If I have problems I'll just replace it.

charlie

Post pictures of your bike, new bottom bracket and the tool they 'Gave' you which is awesome. Those tools aren't Cheap.

Actually the asking price for the tool was $9.95 new, he gave me a used one. Also threw in a set of crank bolts.

charlie

next time in, donate some cash for their pizza kitty or bring a couple of six packs of soda (call to
determine their preferences). they treated you well and deserve an acknowledgement.

That goes without saying

charlie