Bottom bracket help - CAAD9

[donfisher]

I’ve been chasing down a niggling creak for some time now. Earlier in the year I replaced the rear cassette, jockey wheels, chain and 50T front ring. While doing this I discovered a bit of play in the BB that I think was being masked by a stretched chain. Anyway, there’s a badge on the downtube that says BB30. I looked into these and after a bit of head scratching decided to get someone else to replace it as I still don’t really get how BB30s work and I figured my £25 Icetoolz kit wouldn’t be up to the job. I was away a lot last month so couldn’t find a place to have a look at it when I could drop it off.

After a bit more research I’ve actually got one of the 2010 CAAD9s that has the BB30 logo but with a Hollowtech 2 (with adapter). Great stuff. I’ve got the remover for that in my kit. New hollowtech 2 bb ordered. On the way back from work on Friday it was making some really nasty grinding noises but luckily the CRC parcel was there waiting for me.

I got the crank arms off and visually the drive side bearings looked fcvked especially next to the new one. The BB part just would not budge at first. In the end as I was near an aneurism it did start to slightly turn – for the record I was turning it the right way - both sides were turning though which at a guess is not good.

My thoughts are that that whatever I’ve got in there for the BB to screw onto is now loose in the frame. Also that the threads that the BB screw onto must be quite well bonded to the external bearing bit.

Is this something that could be fixed by a good mechanic or is this something that might end up costing more than the frame is worth? I’ve not tried plusgas or similar nor have I tried heating anything up yet as I ran out of time and really didn’t fancy adding to the problem.

Cheers

[Dixie]

BB30 are push fit. No screwing required. You should be able to tap the old bearing out with a big flat screwdriver and hammer. You'll need a press tool to get the new bearings in.

Also, your BB30 chainset wont fit into a Hollowtech bracket.

[donfisher]

That's the thing. It says BB30 on the frame but the BB is one of these:



Presumably there's treaded cups or a sleve in there for it to screw into?

[anonymous-user]

Probably something like this:

http://www.wiggle.com/fsa-bb30-conversion-kit/

[Dixie]

Ahhh Now I follow you.

Is there anyway you could get a second shell tool on the otherside to stop the other side turning?

Might just be better to let the bike shop take a look.

[donfisher]

Dixie said:

Is there anyway you could get a second shell tool on the otherside to stop the other side turning?

Yep, went and bought one but was was having dificulty getting one turning against the other cleanly. Then I figured that even if got one off, the other side will still be stuck on the adapter and I could end up making that worse.

Dixie said:

Might just be better to let the bike shop take a look.

Agreed.

[anonymous-user]

If you can get one side off, you should be able to press the entire adapter out of the bottom bracket. With the adapter removed you might stand a better chance of getting some purchase on it (carefully in a vice for example) to remove the other stubborn threaded bearing.

[donfisher]

Booked it in at the Welsh Cycling Chain for a BB replacement. Dropped it off yesterday before work and picked it up on the way back. Either I was doing something stupid or having the right set of tools and a proper workshop meant that they were better positioned to get the old BB off. I suspect the former tbh.

10/10 for service, ease of use and workmanship by the looks of things. I did try to use a more independent LBS but after being told I'd need to wait 2 months, need to drop it off after 10am, need to pick it up within 2 hours of the repair being collected and all sorts of other random conditions to enable them to repair my bike they can all just FRO. I'm glad I've managed to find somewehere local, that has sensible working hours and who can store a bike before or after they've worked on it.

Click and collect means that I also make sure I get the right parts put on it.

The drivetrain felt like new this morning - as it should I suppose - and despite the rain it was so much better than trying to do 5 miles in half an hour through a million sets of traffic lights on a Boris Bike.

[donfisher]

Back to this. Creaking and clanking started again after only a couple of hundred miles.

I've just pulled the cranks off again and noticed this on the inside of the crankset (Tiagra FC4550):



Should the plastic bit be there?

Here's what another one looks like online:

http://d3d71ba2asa5oz.cloudfront.net/43000093/imag...

Thanks

Don

[upsidedownmark]

Plastic bit - not 100% sure but I suspect it's the bearing face seal off the old bearing. Fairly sure it shouldn't be there.

On a more serious note, I suspect the reason you're creaking is that the crank is fecked. It should be smooth from where the radial grooves end right out to the inner face of the spider - a fingernail shouldn't catch. Looks like you've got a bunch of grooves and steps; has been ridden for some time with a seized bearing most probably. If that isn't causing the creaking, it's at least loading the bearings badly and probably not doing the BB much good at all.

Good news is that a tiagra/105 crankset isn't expensive. Make sure you look at what length your cranks are (back face, near the pedal thread) before you order..

Edited by upsidedownmark on Sunday 6th July 17:28

[donfisher]

upsidedownmark said:

Plastic bit - not 100% sure but I suspect it's the bearing face seal off the old bearing. Fairly sure it shouldn't be there.

Thanks - that's what I was thinking.

upsidedownmark said:

On a more serious note, I suspect the reason you're creaking is that the crank is fecked. It should be smooth from where the radial grooves end right out to the inner face of the spider - a fingernail shouldn't catch. Looks like you've got a bunch of grooves and steps; has been ridden for some time with a seized bearing most probably. If that isn't causing the creaking, it's at least loading the bearings badly and probably not doing the BB much good at all.

That was going to be my nest question. bks.

[Justin S]

You had a seized BB with has spun on the crank and fecked the crankset. I hope they fitted a decent BB and not a cheapy one, as the cheap ones are not that well sealed, if at all in the Tiagra, 105 range and do need regular greasing.

[upsidedownmark]

TBH I've never had a problem with shimano ones - they have a pretty easy life on a roadbike - the 105 one that was fitted when I bought the bike started getting a bit gravelly after 4 years.. think it cost me about 17quid for a new ultegra one.

Sorry to be the bearer of bad news, but hopefully it'll shut the creak up New cranks shouldn't set you back more than 50quid - usual suspects, wiggle, CRC, ribble etc.

[Justin S]

Have a look at Merlins for Shimano too. Planet X has an Ultegra 6800 BB for £12 !! At that price, I wouldn't look at anything else.
From experience ( including having a Tiagra BB on my Cube), Shimano don't like to put grease in them, like their hubs. The sealing on them is woeful. If you do fit a cheaper BB, then prise out the plastic top hat, pry out the seal and bung some decent grease in there. If its packed with grease, water will have less chance to get in there.
When I went to a localish bikeshop, he had a bucket just full of cheaper Shimano BB's , all knacked. So I guess its not just me and my mates who have found out through seizures.