# Rattle in my CR1 traingle



## rbutler (Jul 12, 2007)

*Rattle in my CR1 triangle*

I've recently purchased a CR1 (2005 vintage, used -- some scoring at the peak of the seat stay beneath the brake housing and on the chain stay near the derailleur-side dropout, but appears a sound frame -- Record gruppo, Kysrium wheelset; though it surely has been ridden, overall there is relatively little wear evident on the drivetrain, and, in general, the bike is in like-new condition) and its my first all-carbon frame, so I'm feeling it out in the early days of ownership. 

All good thus far (really love the ride and responsiveness), except for an unnerving rattle (akin to vibration) emanting from what sounds like the rear triangle. Of course, that covers a lot of territory (BB, cranks, stays, dropouts, hanger, chain, cassette, rear hub) but here are the conditions when it appears:

If I'm riding on rough pavement, whether pedalling or coasting -- even if its just rolling over a rain-eroded patch or a filled pothole on an otherwise smooth tarmac -- and in or out of the saddle;

If I am not in exactly the optimum gear in terms of resistance (and even when I am and I hit a bit of rough);

And, an anti-sympton -- if I am in the center of the cassette on either ring, it's less noticeable. (At least, on my last ride.)

While all of this leads me (first) to the chain -- and I am aware of some criticism about the wearability of Record Ultras -- it does not appear loose at any position on the rings/cassette. I go 6' 2'' and 210, but I don't think it's a weight issue, as combined with the bike, it's near enough to 20% under the Scott-recommended 117-kg max. load that I've seen quoted in another string. I've performed the usual diagnostics (visual checks and what mech. tests I'm able in my rather limited workshop) and all appears to be okay. The vibration doesn't affect the ride -- I'm not feeling it but hearing it -- though whether that is the effect of the shock-damping technology, I cannot be sure (nothing to compare it to). Equally, I'm not sure whether this is just a characteristic of full carbon frames, or of CR1s, whether it's something else (integrated fork, headset, steerer) or perhaps I've just got the new-bike yips. Still, it doesn't sound nearly as smooth/tight/solid as the non-carbon and mixed-frame bikes I've owned/ridden. 

Want to be forearmed before heading to the LBS, and I'm in Europe and don't possess the full compliment of jargon, so any help/ideas/advice is welcome and appreciated.

Many thanks!

RB


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## rbutler (Jul 12, 2007)

*Problem lock(ring)ed down.*

And it is a loose cassette. 

Had the bike out in a heavy rain and thinking that it might be a good idea to disassemble and clean/lube.

Any thoughts?


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## California L33 (Jan 20, 2006)

rbutler said:


> And it is a loose cassette.
> 
> Had the bike out in a heavy rain and thinking that it might be a good idea to disassemble and clean/lube.
> 
> Any thoughts?


Had a loose cassette once- took me ages to figure it out. What do you want to take apart and clean? One rain ride shouldn't wash the grease out of anything. You do want to take care that your chain doesn't rust, though.


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## rbutler (Jul 12, 2007)

Case (long) closed. Belated thanks to all respondents. 

RB


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