[Green Dragoon]

Hi everyone-

2010 Trek Madone 5.0.....DuraAce cassette.

I've put 900 miles on the bike.

Tonights ride: every once in a while, when starting to pedal from a stand still or while coasting, the cassette will "clunk" loudly, while "starting up". This, is when under a little bit of a load ....doesn't have to be drastic though.

Also, it can happen in any gear. It doesn't appear as though the bike is trying to shift up or down.....there is no skipping or anything like that, after the clunk.

Any thoughts?

Thanks in advance.

 

[tconrady]

My guess is that it's not the cassette but the rear hub of the wheel. It sounds like a pawl/spring may be sticking in the freehub. Just a guess though.

 

[Green Dragoon]

My guess is that it's not the cassette but the rear hub of the wheel. It sounds like a pawl/spring may be sticking in the freehub. Just a guess though.

ahh.....hmm...yes, I think you could be right.

Is this something I can "service"....if I remove the cassette?

Thanks in advance.

 

[tconrady]

ahh.....hmm...yes, I think you could be right.

Is this something I can "service"....if I remove the cassette?

Thanks in advance.

I service all mine but I feel fairly comfortable doing such things. I'm assuming you're riding either Bonti Race Lites or Race X Lites...haven't worked on those in a few years....but you can do it yourself. You might want to a search and see if you can find a formal breakdown/service release for the hub if you're not sure. Seems like the last set of Race Lites I worked on the freehub came off pretty easily...as in I removed the cassette and just pulled it off. It was held in by an o-ring that kinda locked or seated when you pushed it together. Just be aware they might've changed the design since then. I may still have the remnants of it in the basement. I'll meander down there between innings and see if I'm remembering correctly.

Having said all that...it sounds like you've either got some gunk or something slowing it from engaging. It could also be something with the spring that keeps pressure on it to engage. I would give it a good cleaning (just wipe it down really well...no chemicals) and a light greasing and see if that does the trick. Too much lube/grease and the problem actually gets worse as the grease has nowhere to go.

 

[Green Dragoon]

I service all mine but I feel fairly comfortable doing such things. I'm assuming you're riding either Bonti Race Lites or Race X Lites...haven't worked on those in a few years....but you can do it yourself. You might want to a search and see if you can find a formal breakdown/service release for the hub if you're not sure. Seems like the last set of Race Lites I worked on the freehub came off pretty easily...as in I removed the cassette and just pulled it off. It was held in by an o-ring that kinda locked or seated when you pushed it together. Just be aware they might've changed the design since then. I may still have the remnants of it in the basement. I'll meander down there between innings and see if I'm remembering correctly.

Having said all that...it sounds like you've either got some gunk or something slowing it from engaging. It could also be something with the spring that keeps pressure on it to engage. I would give it a good cleaning (just wipe it down really well...no chemicals) and a light greasing and see if that does the trick. Too much lube/grease and the problem actually gets worse as the grease has nowhere to go.

THANKS. VERY kind of you to take the time to respond. I'm "comfortable" with doing such things. I'll admit, I was more comfortable 25 years ago before everything was "all sealed up".

Thanks again.:thumbsup:

 

[tconrady]

I wasn't into this ballgame anyways....waiting to see if the Braves get rained out and this was on....went down into the basement and found the hub. I snapped a few shots of it. I was remembering correctly as the freehub just pulls off. I think this was off a '04 or '05 model but I'm not entirely sure.

Hope this helps you out.

 

[Peanya]

It's not necessary to remove the cassette to clean the pawls.

 

[Green Dragoon]

I wasn't into this ballgame anyways....waiting to see if the Braves get rained out and this was on....went down into the basement and found the hub. I snapped a few shots of it. I was remembering correctly as the freehub just pulls off. I think this was off a '04 or '05 model but I'm not entirely sure.

Hope this helps you out.

Outstanding! You're very generous with your time. It's people like you that make this forum a great source. Thanks again.