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SC Will
07-09-2006, 05:01 PM
Hi folks

I recently bought a new bike (look 585 with DA-10, shimano compact crank and Ksyrium ES wheels).

I do have an issue however with shifting

About two or three times per ride, typically while I am in the big chain ring, and in the middle of the rear cassette (12-27) the chain will not engage right away and the crank will spin without reisistance for 90 degrees or so. Recently this resulted in my foot disengaging from my pedal

Needless to say this is frustrating!

I am not sure why this is happening. The only thing that I have identified that may be a culprit is that there seems to be some play in the cassette. When I push on the cassette there is clear movement, 1 or 2 mm rocking back and forth. I don't know if this is because the cassette is not seated properly on the freehub or if the freehub itself has play in it. I checked the lockring and it was clearly tight. I returned the bike to the LBS for a checkup and they said that the problem had been fixed - the spacers had been placed incorrectly, but the play was still there and I had the same problems on my ride today.

Can this play in the cassettee cause the shifting problem I am experiencing?

Any thoughts on what the best way to fix this problem?

Thanks in advance

Will

gone
07-09-2006, 05:34 PM
is that there's no spacer between the freehub and the cassette. I have the same combination (DA 10 on Mavic Ksyrium) and there is a spacer that comes with a new cassette that is supposed to be the first one on the freehub. Note that this is packaged separately from the cassette itself and it's different from the intra-cassette spacers in that doesn't have indentations for the splines on the freehub. It goes on before you mount the cassette. If you don't have it, you will definitely have play. Take your cassette off and if there's no spacer you've found your problem.

Hope this helps.

Jeremy
07-09-2006, 05:45 PM
Hi Will,

What you describe may be the cassette body skipping forward. If so, this is a hub problem, not a shifting problem. Sometimes the internal pawls are sticky with grease and they do not open properly. Also, you said that the casette stack has play on the cassette body even when the lockring is tight? This should not be the case. The Shimano 10sp cassette stack requires a 1mm spacer behind the stack on any 9/10 sp compatible hub, but not on the D/A 10sp only hub. This spacer comes with the cassette. There is also a spacer that Mavic uses on their Shimano cassette body. Your set up needs the Mavic spacer AND the Shimano spacer. If it is properly set up, the cassette stack should have no play. If there is enough play, the chain could ride between the cogs and cause what you describe. Remove the cassette stack and look for the silver 1mm spacer that needs to be there. If your cassette body is loose on the hub, all of the cogs will move side to side in unison, so you should be able to determine if the casette stack is loose, or if the cassette body has play.

SC Will
07-09-2006, 06:19 PM
Hi folks

Thanks for the replies

To clarify, I am convinced that the problem is that the chain will sometimes ride between the cogs when I am shifting, resulting in a temporary period of no resistance before the chain seats on the new cog

There is a spacer between the freehub and the cassette stack

If I understand Jeremy's post correctly there needs to be two spacers? I don't think there are two spacers but I will check tonight. Are the two spacers lined up one next to the other?

Thanks

Will

Jeremy
07-09-2006, 07:15 PM
If I understand Jeremy's post correctly there needs to be two spacers? I don't think there are two spacers but I will check tonight. Are the two spacers lined up one next to the other?

Thanks

Will

Hi Will,

Unless Mavic has changed their Shimano compatible cassette body recently, you will need their spacer, and the Shimano spacer. Mavic wheels are directly convertible from Shimano to Campy. Shimano cassette stacks require less space than Campy. To address this, Mavic uses a spacer that positions the Shimano cassette stack properly relative to the dropout. Shimano 10sp cassettes will work on 9/10sp hubs, but only with the supplied 1mm thick silver spacer. There is a recess in the back of the alloy carrier on Shimano 10sp cassettes. This recess needs to be filled in if you are using the cassette on a 9/10sp hub. That is what the spacer is for. Without it, the lockring will bottom out against the outside surface of the cassette body before it hits the first position cog. That is why the cogs are loose. I hope this helps.

Jeremy

SC Will
07-09-2006, 10:44 PM
Hi everyone

I removed the cassette. Both of the spacers are present. The cassette is secure on the cassette body, but there is play in the cassette body itself.

Any thoughts on how to fix this problem?

Thanks in advance

Will

SoCalSteve
07-09-2006, 11:11 PM
Hi everyone

I removed the cassette. Both of the spacers are present. The cassette is secure on the cassette body, but there is play in the cassette body itself.

Any thoughts on how to fix this problem?

Thanks in advance

Will

Try a different cassette.

I cant see it, but maybe the tolerances of that cassette (or spacers) are not "correct".

Good luck,

Steve

Jeremy
07-09-2006, 11:47 PM
Hi everyone

I removed the cassette. Both of the spacers are present. The cassette is secure on the cassette body, but there is play in the cassette body itself.

Any thoughts on how to fix this problem?

Thanks in advance

Will

Will,

The cassette body is held in place by a threaded end cap on the drive side. it has a 5mm allen recess in its' end. The left end cap is removeable by hand, exposing access to a 10mm allen recess. Use a 10mm allen wrench on the left side and a 5mm allen wrench on the right side and make sure that they are tight. If there is still play, the hub should be completely disassembled and serviced properly.

Jeremy

SC Will
07-18-2006, 11:50 PM
Thanks to all who posted replies!

Just wanted to post an update/ask a question

Last week I took the wheel in to the LBS

The mechanic replaced the cassette body and that fixed the problem with play in the cassette ... or seemed to

I took the bike out for a couple of rides this weekend and initially things seemed to be just fine. However, after about 30 mikes I started to have trouble again with shifting. After the weekend rides I checked the cassette body and the cassette body seems to have some play in it again.

I took it back to the LBS and they are puzzled. It is a little awkward as the bike shifts fine in the bike stand. One mechanic said "that play in the cassette is normal." Which leads me to my question - is play in the cassette normal? Should I ask the LBS to send the wheel back to Mavic?

Any suggestions or ideas welcomed.

Thanks Will

vaxn8r
07-19-2006, 04:51 PM
Get another opinion. Preferably from a shop that sponsors a race team.

gone
07-19-2006, 05:20 PM
I took it back to the LBS and they are puzzled. It is a little awkward as the bike shifts fine in the bike stand. One mechanic said "that play in the cassette is normal." Which leads me to my question - is play in the cassette normal? Should I ask the LBS to send the wheel back to Mavic?

Any suggestions or ideas welcomed.

Thanks Will
Find another bike shop or mechanic. There should be no play in the cassette. I've got two sets of Mavic Ksyrium SL's with 10 speed cassettes on them and zero play. Jeremy gave you good advice, check to make sure the freehub assembly itself is tight. If not, tighten as Jeremy described. If it is tight, the freehub needs to be serviced.

This ain't rocket science, there aren't that many moving parts there and it's a pretty simple assembly. If the freehub assembly is tight the only remaining possibility is it's worn out.

SC Will
07-23-2006, 04:22 PM
Another update:

I have a new Look 585 with DA 7800, shimano compact crankset and 12-27 cassette

I have been having shifting problems, which I initially thougt were related to a small amount of play in my Ksyrium ES cassette body. Specifically, shifting into the 16 or 17 tooth cogs (cogs 5 and 6) intermittently results in the chain riding between the cogs and the crank freewheeling forward without resistance.

The LBS recently provided me with a loaner wheel where the cassette body had no play. However, this has not fixed the problem. Is this shifting issue related to the cassette, the compact crankset or possibly an aftermarket removable link in the chain? Any suggestions on how to fix the problem?

Thanks in advance for any input.

Will

05Fierte TI
07-23-2006, 05:57 PM
Is it possible that it is the chain. If the chain is slightly narrow, it could slide between the two cogs. Is the chain out of spec? Have you tried a second chain without a quick release link?