Sponge Posted February 16, 2013 Report Share Posted February 16, 2013 (edited) Hey, I'm currently riding a Leeson (thanks again Matt!) and need to replace the BB to use some new cranks. After removing the old cranks it seems the BB is a modified cartridge with an ubertight press-fit and a large circlip covering both ends. -How does one go about properly removing this kind of BB? -Is it normal for the axle to be more exposed on the driveside and the non-driveside to be half-covered by the shell? (driveside of axle sticks out 6mm more than NDS, unsure if this is a standard for Leesons?) -The frame's shell is 88mm wide but the cartridge hidden inside is considerably narrower- if I want to fit a new BB inside will I need to get a 68 or 73mm? Any help or insight from other Leeson owners or anyone who's familiar with these frames would be much appreciated! Thanks! Sponge edit: photo for clarity: Edited February 16, 2013 by Ares Quote Link to comment Share on other sites More sharing options...
CurtisRider Posted February 16, 2013 Report Share Posted February 16, 2013 You will have to get a new bb turned down to fit, and the old bb pressed out. It may be worth speaking to Clive Leeson about getting a BB done. You have an amazing frame there, I rode it when Dan had it and it was one of the best bikes I have ever had the pleasure to play on, so flicky! Quote Link to comment Share on other sites More sharing options...
grant wildman Posted February 17, 2013 Report Share Posted February 17, 2013 The bb fitted will be a standard Shimano un72 or the like . Clive removed the threads and circlips them in the frame . You can remove them yourself , just remove the circlips and should knock out (well dose on my leeson ) Clive I'm sure will help you but dose work on his on time so wouldn't expect anything to happen fast . Speak to Mr Purdon (I assume thats whom you bought it from?) the man knows most things 24 . Quote Link to comment Share on other sites More sharing options...
smelly joe Posted February 17, 2013 Report Share Posted February 17, 2013 Snapped the bottom bracket in mine a few years back and there not as bad to change as you think with a big hammer some grease and a pair or circling pliers! As long as you can get a vernier on the old shell and get somebody or company's to machine it down to the correct dimensions for you. Then it's simply a case of greasing and hammering it in and re-circliping. As for the axle sticking out thurther on the drive side, yes it should to give clearance for the chain ring and bash guard, the non-drive side should almost be flush up againstl the frame with a 2-3mm clearance with the crank arm on. I might have some old photos of when I did mine ill try dig out for you. Be sure to measure the axle length of you old BB correctly after machining a shell for one BB I bought the axle was to short so cranks grinding on bottom bracket shell wasn't very good. Quote Link to comment Share on other sites More sharing options...
Sponge Posted February 17, 2013 Author Report Share Posted February 17, 2013 Awesome, that all sounds fairly straightforward. I did some researching around and it seems on (some?) Leesons the BBs are either epoxy'd or loctited into the shell after the machining, which if is the case would I need to use a blowtorch to break the bond? Mine is rather stiff, though not quite sure if it's been loctited in or greased as yours is. So is any 68mm cartridge-type BB compatible? So say I asked for a 68x128 Trialtech ISIS BB to be machined down- it would just take some hammering (with either grease or loctite??) and the circlips and the job is complete? if you manage to dig out some photos that'd be great Joe! Still getting to grips with how this all works but it is such a fun bike to ride! Quote Link to comment Share on other sites More sharing options...
Blake Posted February 17, 2013 Report Share Posted February 17, 2013 Awesome, that all sounds fairly straightforward. I did some researching around and it seems on (some?) Leesons the BBs are either epoxy'd or loctited into the shell after the machining, which if is the case would I need to use a blowtorch to break the bond? Mine is rather stiff, though not quite sure if it's been loctited in or greased as yours is. So is any 68mm cartridge-type BB compatible? So say I asked for a 68x128 Trialtech ISIS BB to be machined down- it would just take some hammering (with either grease or loctite??) and the circlips and the job is complete? if you manage to dig out some photos that'd be great Joe! Still getting to grips with how this all works but it is such a fun bike to ride! I've always found the best way to get rid of locktight is to hit it so that the force causes it to kind of crack, So if you what the bb shell a few times (maybe with a rubber mallet?) you should break the bond. Quote Link to comment Share on other sites More sharing options...
Skoze Posted February 18, 2013 Report Share Posted February 18, 2013 Loving the addition of the Reynolds sticker Grant and Joe have got it; as i understand Clive heats it and twats it out with a big hammer, same process when it comes to putting it back in (which could warrant a respray if you go for the heat route) If you can work it out for yourself then that's cool, if not i'll forward you Clive's number. He still does maintenance etc if you ask nicely, just takes a while... Quote Link to comment Share on other sites More sharing options...
Sponge Posted February 18, 2013 Author Report Share Posted February 18, 2013 That's an old photo straight from the Leeson page, back when that frame was new I'll give it a go with the mallet again but if it's still not budging I'll give Clive a call. Just to be certain- is there any specific side I should be smacking it from to get it out? Quote Link to comment Share on other sites More sharing options...
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