Which Bottom Bracket

[huggy]

I know I need a new bottom bracket but which size?

I sure it is a 68mm but the next bit is where I get stumped.

See photo

From end of taper to end of taper is about 135mm?

I am doing this because my crank fell off from what I read it may be damaged and not be fixed on as well again ever but will I damage the new BB if I use the old crank?

Thanks for your help

 

[spandex]

I would say you are all most right I would go for 137mm. But if your crank fell off why are you taking out the BB and not sorting out the crank? you will find it very hard to damage the BB as it is so much harder then the crank.

 

[huggy]

Because it is pitted in the ball baring race and had a wobble in it. It is 15 years old (but not thousands of miles).

Where do I get a 137mm BB from?

 

[Chrisz]

I'd just get a cartridge BB and have done with it. You may be lucky and find the right cops/ball bearings to fit but why bother?

Measure the BB shell (internal diameter & width) and get a tapered cartridge BB to suite (remember though that Shimano & Campagnolo have differing tapers)

 

[spandex]

I get 137 from that your ruler is around 2mm off on the left hand side. If you are not shore just take it into your LBS and say can I have a sealed BB in that size please.

 

[huggy]

Measure the BB shell (internal diameter & width) and get a tapered cartridge BB to suite (remember though that Shimano & Campagnolo have differing tapers)

This is what I was planning to do but then got stumped by this second measurement on this list will any of these fit?

http://www.wiggle.co.uk/p/cycle/7/Shimano_UN54_Tapered_Bottom_Bracket/5360027179/

Set aside Shimano vs Campagnolo for the moment , but it is a British eagle built of 531 tubes if that helps.

 

[spandex]

Well all those sizes are wrong for what you need so all I can say is ask your LBS.

 

[PpPete]

Cartridge BB with 137 mm spindle ?
Don't know where you are going to find one of those.
Is is pitted on the spindle or just on the cups? You might me able to/ have to reuse the spindle, and just replace cups & bearings.

 

[huggy]

Well that was my thinking on it as well, am I getting mixed up on the measurements? hence I did the photo (and 135 or 137 is not really the point). Its not like its a hand built bike or anything its has a Shimano 300 LX chain set. I know the virtues of and LBS but I have no idea when I will be able to do the 20 mile round trip to one that might or might not be helpful, in my experience if you don't know what you want in a LBS you just get palmed off with any old rubbish they have hanging around. Like these crank arms that have fallen off because having looked into it seems they don't fit properly.

 

[Chrisz]

huggy, sounds like you've had similar experiences to those I had with my LBS many, many years ago. Once I realised that the buggers were selling me any old tat I found myself a not so LBS about 40 miles away. A bit of a yomp but well worth it for the service they provided.

It's certainly worth having a look around to see if you can find a more suitable shop if you don't feel you can trust your current LBS. They are (to me) a little bit like garages - once I find one I like and trust then I stick with it.

Perhaps if you can tell us where you are based someone could reccomend a decent LBS to you?

 

[Browser]

IMHO, in an LBS worth it's salt you'd be able to take the bike in, together with the collection of removed bits, ask for a cassette B.B. and they'd be able to find one to fit, hopefully offering you two or three choices into the bargain. I recognise the P.I.T.A. that it is when this means a trek but in the end it's worth it

 

[OLDSHUNTER]

pack n stack

dont worry about using on bike if pitted just put bearings in loose ones are better and pack with grease should be good for another few hundred miles or so .11 loose bearings on each side if i remember right