Transmission database - for all your crank / bb / bottom bracket questions

Help please!

I just bought a Peugeot frameset circa 1982-1985. It had a bottom bracket already installed, but no crankset. I stripped a crankset off an old Carrera road bike I had, a Prowheel Forged Gloria. I've taken the small ring off it so it's just a single 50t chainring.

Problem is, when fully tightened, it rubbed against the bottom bracket on the non-drive side due to the shape of the cup, which sticks out rather than hollows out. So I stripped that bottom bracket and am now trying to install the BB that came with the Carrera (CH 2J is the only info I have on the name of the BB).

The CH 2J fastens to within 3 or 4 turns of being fully fastened then completely seizes up. This is after degreasing and cleaning all threads with a toothbrush, then greasing them all up again.

Anyone have any ideas what the problem might be? I thought either the threads are gone, or not cut deep enough into the shell, but when I shine a torch through the other end I can see that they clearly are. Took it into a couple of LBSs who just said I'd need to buy a new BB or use a threadless one...

Cheers,

Tom

Right peeps I'm having trouble under standing how to pick the right BB to buy, cos I'm very puzaled about the sizing.

I have a FSA RPM crankset with a square taper and my fram has a 68mm shell width, from what I'v read online think my rear chain line is 40mm.

Any help and advice on what will fit propperly an what overall lenth it should be?

Thanks!

Checked the transmission database? Best to go off what someone else has found works before we go trying to calculate this stuff.

Hi, I have a query regarding bottom bracket casings; so I have a 1984 cbt italia track frame and the bottom bracket which currently resides in the frame has some play, this bb was in the frame when purchased and I believe to be the original.

I decide to take the frame to my lbs to remove the bb with the intention to replace with a veloce 111mm for my campag record pista chainset. The lbs confirm the threading is italian but unfortunately can't get hold of the italian threaded veloce bb. After a bit of searching I manage to track one down and return to my lbs for fitting.

So it turns out the cups are too large for the casing. Myself and the mechanic are a bit stumped. The current bb (an open bearing stronglight) has a thread diameter of 35mm whereas the veloce has a diameter of 36mm. I must admit before this point in time I wasn't aware that this was a possibility, my mind was more concerned with whether a 111mm bb would cause the crank arm to hit the chainstay.
What the heck is going on? Does this mean that I can't purchase a modern replacement bb?

The mechanic kindly rebuilds the stronglight bb in an attempt to cure the play which plagued the bb to begin with. We agree that i'll run it and keep a close eye on it while considering solutions to the problem.

My last query, are stronglight bottom brackets iso taper (or can they be jis)?

Sorry for the ramble, any help massively appreciated.

EDIT: Hmm maybe this is it in French thread variant: http://velobase.com/ViewComponent.aspx?ID=9E4FC01C-5918-4822-B197-88D4806EC74D&Enum=119&AbsPos=100

Will DA 7600 cranks works ok with (Dura-Ace FC-7400 bb) on 112mm axle?

Stronglight JIS and Sugino75? And which axle length for 43mm'ish chainline? http://www.planet-x-bikes.co.uk/i/q/BBSTJP400/stronglight_jp_400_jis_bottom_bracket

^ Sugino 75s IIRC take an ISO taper, so the JIS spindle won't work. Why get such a cheap BB on an NJS cranks?

^ Sugino 75s IIRC take an ISO taper, so the JIS spindle won't work. Why get such a cheap BB on an NJS cranks?

Yeah the S75 JiSO is messing with my mind - what about the UN55 ISO in 107mm? http://www.chainreactioncycles.com/Models.aspx?ModelID=71369

I'm not able to put down the wattage S75 is designed for, therefore comprimi(down)zing.

If you want a budget solution why not just get the Veloce in 111mm that plenty of people are running as per the table above? I used one with my SG75s and it was fine, and can be had for £20.

If you want a budget solution why not just get the Veloce in 111mm that plenty of people are running as per the table above? I used one with my SG75s and it was fine, and can be had for £20.

Thanks - but the Veloce is discontinued in all webshops, so seeking alternatives in the same price range.

Ah. I got mine from here and they let me put one into a basket just now ....

http://www.parker-international.co.uk/13257/Campagnolo-Veloce-Bottom-Bracket.html?referrer=froogle&utm_source=google&utm_medium=froogle&utm_campaign=pid13257

(trying to be helpful. If you can find the veloce and need the tool you can borrow mine. good luck with the search.)

Ah. I got mine from here and they let me put one into a basket just now ....

http://www.parker-international.co.uk/13257/Campagnolo-Veloce-Bottom-Bracket.html?referrer=froogle&utm_source=google&utm_medium=froogle&utm_campaign=pid13257

(trying to be helpful. If you can find the veloce and need the tool you can borrow mine. good luck with the search.)

Thanks for your link - making S75cheapskating a bliss. I'm from Copenhagen, guess your tool doesn't make the reach or is inoperational at that distance :]

Stronglight 2000 (48)+ Stronglight JP400 / 107mm JIS + On One + On One 1/8" (17) (42mm chainline) = Chisa

also -
sakae sr (mounted on inside) + tange + on one + on one. that gave a pretty good 42ish line. chisa

Send back to On One, for either a replacement or threads to be retapped. Seems likely to be a quality control issue!

I dont know if this is a BB/Crank/Chain problem ... or if it's even a problem at all but....

if I rotate my cranks backwards (essentially pedalling backwards quickly but not on the bike) I have noticed something makes a loud clunk noise on every second rotation. It sounds like it might be the chain but im not sure.

Any ideas? and is it something I should be worried about? It doesnt seem to do if I spin forwards.

stiff chain link possibly

stiff chain link possibly

Would that be something worth worrying about?

not really no if you can find it (give chain a clean down and wiggle each link) theres a few things that can be done to loosen (google will give better advice than me)

sweet nice one.
I'll have a look at it tonight.

does your chainring have an odd number of teeth? Does the clunk happen at the same point on every second revolution?

If yes, and there's something wrong with one of the teeth, it would meet inner chain plates on every second revolution.

does your chainring have an odd number of teeth? Does the clunk happen at the same point on every second revolution?

If yes, and there's something wrong with one of the teeth, it would meet inner chain plates on every second revolution.

nope 48 tooth chain ring.

as far as I can remember it does happen at the same point every second revolution though. Chain ring is brand spanking new, as is the chain.

Whole bike was bought new just over a month ago.

maybe your chain is 96 links long and there's something wrong with one link.

Edit: never mind

I'll have a look at it tonight and see what I can work out.

Cheers for your help guys.