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Technical & Reference Section => Tech and Restoration => Topic started by: level on January 02, 2011, 10:57 AM

Title: BB bearings?
Post by: level on January 02, 2011, 10:57 AM
Hey guys, I've got a creaking on hard pedaling which I assume is the bottom bracket bearings, the bb had a far bit of play when I recieved the bike, but I cleaned it up, re greased and adjusted, it's still there tho. So I guess I need new bearings, I think they mite be American but would you guys know? It's a 96 diamondback venom pro.

Cheers guys

J
Title: Re: BB bearings?
Post by: TwoBobRob on January 02, 2011, 11:01 AM
One or three piece crank?

Open or sealed bearings?

Title: Re: BB bearings?
Post by: kuwahero on January 02, 2011, 11:06 AM
If its an Aluminium frame there's a high chance it might be the frame.

They can develop creaks and tings over time. Try replacing bb first then you will know

Replaced two bb's in my mates 90's floval flyer and still has the same issue.
Title: Re: BB bearings?
Post by: level on January 02, 2011, 11:17 AM
Sorry,

It's a 3 piece crank, the bearings are in a cage and the seat they sit against comes out too. There is also no play in the bb.   I think its CR-MO but not really looked into the bike too much.  But, I've just remembered that one pedal has shot bearings, proper shot! Maybe this could be it?

Cheers guys.
Title: Re: BB bearings?
Post by: TwoBobRob on January 02, 2011, 11:23 AM
Most commonly on 3 piece cranks, it's the crank arms themselves. Pop em off, clean inside, all hardware and the axle itself  spotless and reassemble with copper grease on everything - axle, inside arms and all bolts.

This may sound daft, but you often feel a creak. Get you hands on it and start twisting and pushing, whatever. Might show summat  :daumenhoch:

Sort them pedals out anyway, so much nicer when they run smooth.

Title: Re: BB bearings?
Post by: Gary72 on January 02, 2011, 12:22 PM
If its an Aluminium frame there's a high chance it might be the frame.

They can develop creaks and tings over time. Try replacing bb first then you will know

Replaced two bb's in my mates 90's floval flyer and still has the same issue.
My Redline with a euro BB kept creaking, I bought a new Profile BB. Followed the instructions on profile's website, It says to wrap ptfe tape round the threads, Never heard this before but done it anyway, No noise since.
Had tried new bearings before replacing complete BB.
Title: Re: BB bearings?
Post by: TwoBobRob on January 02, 2011, 09:10 PM
An isolator basically.   Same idea as my smother it in copper grease approach  :)

Title: Re: BB bearings?
Post by: level on January 02, 2011, 11:11 PM
Ok, took it out for a ride tonight (8 miles), and the sound got worse, and it felt so bad to the point where I felt guilty for pedaling! Anyway, got back, stripped the bb down and 3 bearings from the non chain ring side had come out of the metal basket! Took it out and the rest fell out! I've re packed it all with copper slip, and got it pretty tight, but the creak and now clunk is still there.

Reckon I'll be needing those then! So, do I just buy the bearing set of eBay? And is it American?

I also swooped out the pedals from my DH rig, and it made a huge difference to the noise and feel, no point in re building them I guess?

J
Title: Re: BB bearings?
Post by: rick1970 on January 02, 2011, 11:37 PM
Stupid question approaching,,,whats a us bottom brkt i assumed all o/s bbs where the same, as ours or anywhere else :idiot2:
Title: Re: BB bearings?
Post by: HEYWOOD BMX on January 02, 2011, 11:57 PM
 :) Rick,are the cages/bearings sitting in cups pressed into the frame? Same size as a Burner,DP,SE? If so then you`ve got a US bb.Any local bikeshop(but not L-Lakes!) should have a full set or balls & cages.
Title: Re: BB bearings?
Post by: TwoBobRob on January 03, 2011, 05:27 PM
What you have there is an loose-ball U.S. Bottom bracket.  And yeah, you need a new 'un!  Don't pack your new bearings with copper grease though, be sure to use a good automotive or lithium grease on those new bearings.

All that said, if you're going to be riding a fair bit then the best thing you can do is upgrade your crankset completely. Treat yourself to a set of Flights or Profiles. You'll most likely save a bit of weight and they come with a sealed BB as standard  :daumenhoch:



Title: Re: BB bearings?
Post by: level on January 08, 2011, 01:11 AM
Hey guys,

So, new bearings in and grease up with a decent castrol lithium grease. It's made a hugh difference, but the pedals are worse than I thought. Does anyone know where I can find the bearings for pedals? I belive them to be the original if not old school Odyssey's so I'd like to restore them, plus it stops me working and gets me in the garage. I can post pics if needed.

Cheers

J
Title: Re: BB bearings?
Post by: kuwahero on January 08, 2011, 01:14 AM
hi j

are they loose bearings or sealed. stick up some pics it always helps
Title: Re: BB bearings?
Post by: brettypeeps on January 08, 2011, 01:16 AM
Your local bike shop will some they are normally loose ball bearings just pack em with grease (lithium)
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