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OCLV - bottom bracet squeaking?(12 posts)

OCLV - bottom bracet squeaking?must_pedal_harder
May 12, 2001 7:18 PM
I seem to notice this when I'm really jamming - normal? fixable? typical of all CF frames?
re: OCLV - bottom bracet squeaking?Cliff Oates
May 12, 2001 7:21 PM
Is it the bottom bracket? I put some ti prep on my saddle rails and all was quiet again.
CF frames have Aluminum shell....nmFor Threads.
May 12, 2001 9:50 PM
OCLV - bottom bracketgusriley
May 13, 2001 9:22 AM
1. Re-tighten bottom braket on both sides
2. Re-tighten both cranks
3. Make sure rear wheel skewer is tight! Not snug... tight.

These are 3 things I've found that can cause the noise in a bottom bracket or seem to be from a BB. The fourth I've seen is bad news:

4. Inspect the bottm of the OCLV chainstays where they connect to the bottom bracket for cracks. I witnessed a friend's OCLV frame develop cracks at this location. His bike began to creak and make subtle noises. Trek replaced the frame.

I'm sure my experiences aren't a complete set of possible causes, but every little bit helps.
OCLV - bottom bracketmust_pedal_harder
May 13, 2001 1:20 PM
I was afirad of this - when I first got the bike I noticed white streaks above the bottom bracket which now are apparently small cracks. At first I thought they were just imperfections left over from teh fab process but I guess not.

I suppose I'll be contacting Trek about this soon.
Carbon Fiber lifeSpiderman
May 13, 2001 1:31 PM
I used to be a rower and in crew our boats are made out of carbon fiber. Boats could only be raced, at the elite levels, for one season, if that, because the c/f looses its rigidity. The crew boats are honeycomb with carbon fiber over it, but i would think that as time goes on, c/f will wear out. It will creak, you will start to have problems with the headset, it will become "flexy." I don't know if this happens to bikes as quickly as crew shells, but if you bottom bracket is creaking, than it maybe that the c/f is just beginning to wear out. Talk to your trek dealer about, maybe then can provide a good answer. Also, keep in mind that Trek doesn't make bikes to make bikes. They make them to make money so their bikes aren't as good quality as some others. Hope everything has been helpful and it works out okay.
Names, I need namesSpoke Wrench
May 13, 2001 5:25 PM
Hey Spiderman; Could you provide me with the names of a couple of bike manufacturers who don't have a profit motive? Your comment regarding Trek: "They make them to make money so their bikes aren't as good quality as some others." makes no sense to me at all.
Names, I need namesBob in Indiana
May 13, 2001 8:48 PM
Ditto...why slam someones pride and joy? (that just cost what to ME is a small fortune)
carbon is greatishmael
May 13, 2001 8:23 PM
carbon fiber boats and bikes arent the goes on the water and one uses far as i know all the carbon bike manufacturers have great warranties...i have heard that some of the older treks cracked but things are looking much better for carbon..carbon is here to stay and there are alot of folks who swear by included
carbon fiber framesSpiderman
May 13, 2001 9:51 PM
Okay, maybe the remark about trek is a little off color and i did not mean any personal offense, this is not a personal thread involving opinions, it is about someone who has a creaky bottom bracket. Working in bike shops though has shown me that some bikes are made better than others (obviously). And one of the bikes that are not made so great are Treks.
As for the Carbon fiber discussion, I stated that i am not sure if bike c/f works the same as boat c/f. Crew shells have a honeycomb design with layers of carbon fiber over it. Frames are layers of carbon fiber pressed together or layered over a ballon (there are different ways). A crew shell is designed to be as stiff as possible (like a bike) regardless of what surface it is on. It obviosly isnt going to be used for to absorb road noise. It, like a bike, is trying to be a stiff as possible to transfer the energy of the rower/biker out through the oar/rear triangle. IF the carbon fibers in the shell and the bike frame served the same purpose, as it gets more mileage and flexy, the joints wont be as tight, IE the bottom bracket might get creaky. So to answer the question about a creaky bottom bracket, i simply suggested the idea the possibility of the c/f wearing out already and he could inquire with his trek dealer about this problem. Tha's all.
Off Base S-mangrz mnky
May 14, 2001 10:00 AM
You made the statement:

"A crew shell is designed to be as stiff as possible (like a bike) regardless of what surface it is on."

This isn't really true - it needs to be qualified as stiff as possible for a given weight. I spend a lot of time racing composite sailboats (505 carbon, honeycomb, kevlar, s-glass, etc.) and wave boards. Things made of CF can be flimsy or bomber or somewhere in between. The 505's are still bomber after 15+ years since the class rules discourage one from making a "throw-away boat". It all comes down to how much material one is willing to use. If you skimp on the material and go for a lightest possible layup schedule then things are going to have a short life - nearly _everything_ works this way - CF, aluminum, steel, titainium, etc. Sounds like your crew team went for lightness over durability - I'd love to be in that business - keep selling the same flimsy to the same people year after year. I owned an OCLV for several years and even crashed once with no problems. I've also been totally worked in large surf with rocks and had my CF mast, booms, and fins survive just fine. I've also had some flimsy components die a qucik death when they weren't made strong enough.

Finally if Trek were so skimpy and bottom line profit oriented they wouldn't offer a _lifetime_ warranty on their CF frames - that's a huge outstanding liability that never gets retired and is enough to give the bean counters fits and bad dreams.

Creaking noises can come from _many_ places, but many people assume that it's the BB since it's pedal caedence relaled. Seat post, seat rails, stem handle bars, wheels, crank, chainrings, etc. can all be sources and since they're related to the power applied it corelates well with pedal stoke. CF by itself doesn't make creaking noises, but the joint between the composite lugs and the pre-made tubes will since they are actually two disticnt structures bonded to each other - not a monocoque structure.
its not personalishmael
May 14, 2001 7:20 PM
its too bad if anyone takes anything on here personally...i do disagree though about treks being poorly made...atleast the carbon frames these days are good..all i know is i have a lifetime warranty and that is pretty solid..i also read on sheldon brown's site that the older mechanicaly silver brazed treks were better than alot of fancy hand done did trek get such a bad name, is it there awfull paint jobs, are they too big, not italian enough..