Bottom Bracket Removal - Pics added

you're not stuck with this BB at all - any BB with the same threading (english or italian) and spindle length (JIS if it's for shimano cranks) will work with your existing cranks.

I would get them to remove and fit a sealed unit you then only need to buy yourself 1 tool for future use.

But keep the old one someone on here may have a use for it. Me especially if its a 68mm shell.

Just to clarify -

1. I should change the old BB to a sealed unit
2. The new sealed unit will accept Shimano or SR cranks
3. I could but the tool for the new sealed unit if i want to
4. I should keep the old BB bits - just in case (or sell for vast amounts of cash! - lol)

Is the above correct? Any additions etc please advise

And thank you all for your help so far, i really appreciate it

yep, if you're not worried about keeping the bike 100% period correct, then you're best off getting a sealed BB. You say you have 600AX cranks - are you sure they're that model (FC-6300) and not 600EX (FC-6200/6206/6207/6400)? The AX version has extra large holes for the pedal spindles, and require dedicated pedals, which if you don't have already might be very hard to find.

Look on the back of the crank arms and they should have the model number stamped somewhere, for example "FC-6300" (for 600AX). once you've found the model number, it's easy to know what BB length you require.

you said you're BB is marked 1.37x24, so in that case it's english threaded. From velobase, 600AX cranks require a 116mm spindle if used with an english BB. So any english threaded BB with a 116mm spindle should work fine. if you can't find 116mm, then you'll be fine 1 or even 2mm difference either way, but if you go shorter then make sure you check the clearance to the chainstay! if you get a shimano BB then no problem at all, but the majority of BB units are for shimano (JIS) taper as opposed to campagnolo (ISO).

you only need a single tool (and large spanner!) for most shimano style sealed BBs.

and yes - keep the old bits just in case! personally I never throw anything out unless it's absolutely b*****ed, you just never know when you (or someone else) might need them!

Foz,

Thanks for that, i am getting pedals with the cranks and actually, i had been warned about that, but you can get some bolts/inserts to fit new pedals with the 600ax cranks.

I am trying to keep the bike original but i feel, for useability, this is a fair upgrade. I will keep the old bits - i am a hoarder!

Thanks to all for the BB lessons - i owe you all a beer or two!

no problem! chainreaction have shimano UN55 BBs on sale right now - 116mm isn't an option, but they have 115 and 118. I'd go with 115, just be sure to check the clearance but you should have no problem at all.

Of course, if you're going to get a shop to do all the work then it would be best to buy the BB from them, but you could get them to remove the old one, then buy the new one and correct tool online and fit it yourself.

make mine a black sheep

I had a look at that, not expensive soooooo... why not one of the other 146 BB's?

What are the differences?

Your beer is getting warm! Hot black sheep is not to my taste!

Thanks

If you are not sure then just get your LBS to fit the correct new BB for the cranks that you are going to use.......They have all the tools and it will likely work out cheaper

BITD it was my job to do this sort of thing (cup and cone only) and if I made a mistake and fitted the cranks and the inner chain ring fouled the chain stay then I had to dismantle it all again and the shop took the loss in time and materials..

Didn't make many mistakes

Shaun

Thanks Shaun,

You fancy popping over to NI to fit mine? What are the differneces between the BB's in CRC - should i go with the one mentioned previously?

Beer ready for you!!

Thanks

The UN55 I mentioned was just the first one that appeared on the list... there are much better (and much worse) BBs available, depending on your budget and the use it will be getting.