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Hi I'm fitting a double crank on a racing frame which doesn't have a BB, the cassette is an 8 speed how can you work out what length of BB to fit?...( all parts are Campy if this makes any difference) I know the BB will be an ISO to match the cranks, the front and rear derails are also both 8 speed
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I think the length of the bb required is defined by the crank your using, which model / generation and whether or not it's a triple.
A bb will have been issued to pair with the crankset to provide the correct chain line.
There are secondary issues, like frame clearance which may be encountered but I think the best thing to do would be to look at Velobase or similar and see what bb was sold as part of the group. The measurements will likely be listed there for you to find the same or a suitable replacement.
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Thanks for your reply, my intention is to fit the bike with a double crankset, originally it was fitted with a treble for a touring set up, it was the secondary issues I was afraid of and wondered if there was some kind of formula people used to determine BB lengths, your advice was of some help so thanks for that........
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If it's Campag road double and 8 speed, you'll need 111mm (Record and Chorus switched to 102mm in 1993).
http://www.wiggle.co.uk/tifosi-campagnolo-fit-bottom-bracket/
http://www.wiggle.co.uk/campagnolo-centaur-tapered-bottom-bracket/I think the Veloce has been discontinued, but I'd avoid that anyway as you need a separate tool to install it, whereas the above use the same tool as you remove the cassette with.
PS They are just the first results when I searched: shop around and you might find them a bit cheaper.
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Hi and thanks S.Suffolk, I've managed to borrow a mirage BB 115mm from my friends other frame to use as a reference and will fit the crank today and this looks closer than expected, will definitely find out once I tighen up the cranks, will be great if this works as the rest of the groupset is mirage...
I have looked at the Tifosi BB's before but never used one have you used these before and would you recommend cheers. -
115mm is for triple cranks and the chainline will be 2mm out: whether that works or not you will soon find out...
Yes I've used Tifosi and they're perfectly fine.
Once fitted the BB won't be visible, so having it match the group is neither here nor there: I'd rather the correct length, than the "correct" name.
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The frame I'm working on was originally set up for touring and I'm wondering if this changes how the rear of the frame is designed but maybe not, not seen the BB once fitted is exactly my thinking too, this bike is for my friend and as I'm showing him how things are fitted and replaced, he will get more practise the more removal and fitting we need to do , when measuring this chainline am I correct in thinking its the largest chainring to the smallest cog... cheers
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The chain stays may be shaped to allow more clearance for mudguards if it's a tourer, so it's possible that the larger chainrings used with a double may foul them.
In practice though, it's not usually a problem.
What is the rear OLD? 126mm or 130mm?
What's the frame made of? Steel?
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Cenelli
Never heard of them (not that that means much).
OLD increased to 130mm when 8 speed was introduced, but being steel you can just pull the ends out when fitting/removing the wheel: it's only 2mm on each side.
However, depending on the size of the top sprocket it may foul the chain stay near the dropout: easily resolved by fitting a cassette with a smaller one.
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Its a Reynolds 531 tubing with the Cenelli stamp on the BB shell, we had 2 back wheels both mirage hubs 126mm/130mm unfortunely the 126 hub was too damanged to use, I've put a threaded bar with nuts and washers in the rear dropouts to try and exspand it to 130mm in order to use the 130mm wheel, I was hoping to reuse the axle from the 126 hub but its completly seized,
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"Cinelli" not Cenelli.
Although Cinelli do make frames, they also manufactured frame components such as BB shells, so the bike isn't likely to be a Cinelli (pretty sure they never used 531).
But it does suggest the frame is of reasonable quality, as Cinelli parts weren't cheap.
The 126mm wheel will have a thread on the hub to accept a freewheel (7 speed and below); the 130mm wheel will have a freehub and accepts a cassette (8 speed and above): you should familiarise yourself with the difference.
You can't use the axle from a 126mm wheel in a 130mm wheel: obviously it will be too short.
Using threaded bar as you've described, will do nothing except possibly misalign the dropouts so the wheel is no longer centred.
If you must, then look-up "cold setting"; but it's not necessary: steel will easily flex the required 2mm on each side with no ill effects.
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Hi S.Suffolk, I fitted the crank on the 115mm BB and there is 5.5mm gap between the inner chainring and the rear stay so as you suggested a 111mm will fit, I do know how freehubs and freewheels differ and like you I was always under the impression that a 126mm would be a freewheel and not a freehub untill I began work on this bike, the original rear wheel is fitted with a freehub, Cinelli did as you say make frames and they also did use 531 tubing, I knew the person this bike was made for in the late 80's but I'm not sure if it was specially made for him or if it was one of their existing frames, I do remember him having lots of measuring done at the time, the frame has now been resprayed so the 531 decals have been lost in this process, I will upload some pic's one before the respray were you can just about see the 531 decal, everthing you have said has been appreciated and helpful and I hope the pic's give some kind of light, ps the exspanding I've tried has worked for me before but this time has do nothing...
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Transmission database - for all your crank / bb / bottom bracket questions
Posted by
@kowalski
Hi all - I hope someone can help.
I've got a new Bob Jackson Vigorelli I'm building up, but I'm having issues with the crank spider rubbing on the chainstay.
I've got goldtec hubs, Miche Primato Advanced cranks (JIS) and Miche 107mm BB.
I ran this setup on an older frame with no issues. But on the Vigorelli I torque the crankbolts down and the spider rubs on the stays really badly.
To see if it helped, I got a 110mm Shimano BB.... same problem.
What the heck is the best course of action for me to get this frame up and running with a decent chainline and (hopefully) not dropping too much more moola? Has anyone else encountered this? Thanks in advance.
Ps - the frame does not seem bent.