Bicycle Mechanics - Crazy cassette action when I coast

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pjcampbell
08-06-08, 10:23 AM
On my 07 2.4 wireless PowerTap hub, anytime I coast, the cassette starts going nuts. It violently jerks forward about 1/4 of a turn, then back to original position. I replaced the freehub body (actually my LBS did under warranty) and it stopped doing it for about a mile then started back up. I am familiar with how to remove and replace the freehub body but this was under warranty so my LBS did it. This is a campy freehub.

I am no where near home with limited tools (but I will buy whenever I need to if I can resolve this myself) and have a hill climb TT on Sunday. First, if not the freehub body, what is causing this, and secondly, assuming I am not going to be coasting on a 12 mile climb, can I go ahead and race this ? I do not care if I have to take the chain off at the top to get down.

DMF
08-06-08, 11:52 AM
Got a spare wheelset?
pjcampbell
08-06-08, 12:18 PM
I have plenty of wheels 2700 miles away at home.

DMF
08-06-08, 01:01 PM
On a Powertap isn't there something inside the hub that the freehub body attaches to? Sounds to me like whatever that is is seizing up. Sorry, I have no experience with the innards of Powertaps.
pjcampbell
08-06-08, 02:32 PM
I don't really know either. I've only replaced the freehub body when I went from Campy to Shimano on another wheel. I don't understand how it could be an issue with anything but the freehub body though.
nubcake
08-06-08, 06:46 PM
im not sure if there is any weirdness with powertap internals or have never had one apart. I know they use sealed bearings and some companies still give you a bearing adjustment with sealed bearings, kinda like kings and ive seen tight bearings cause freehubs to act funny like that. If thats not an option with the powertap just call saris and they will tell you exactly what you need to do and weather or not its safe to ride.
pjcampbell
08-06-08, 08:56 PM
It was the bearings. One of them blew up. Now the fun part. The new freehub that they just replaced under warranty that wasn't actually broken, broke.

There is some tiny little piece of pressed metal that keeps the pawl spring from rotating, and it broke off? I don't quite understand the ridiculous design. So I am not sure what to do now. I am going to call Saris in the morning and beg for them to overnight a new freehub body.
nubcake
08-07-08, 08:05 AM
let us know what happens, im currious as to how they handle things with their powertap. I know everytime ive called with bike rack problems it was no questions asked the parts are on the way type service. good luck