# Speed wobble or shimmy?



## grasslander (Mar 23, 2006)

Folks,

Question: Anybody hear of speed wobble or shimy issues with the Pilot 5.2 series?

I have had it happen 3 times on a down hill smooth chip and seal at 34mph. Light trailing rear brake to a stop to bring it under control. 2006 54cm model, in the drops, rear to the seat back, pedal down or pedal at 3, Continental 4000 tires but did it once with the original Bonty tires, and stem at 30mm pointed down. Everything is tight to spec. 5'9 - 175lb rider.

Never at 30mph or less. Any experience? I've go an appointment set with the dealer to check the frame and fork.

Thanks for any input in advance


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## uzziefly (Jul 15, 2006)

All the bolts screwed tightly? 

QR levers tight? Spokes okay?

I rode pretty fast the other day at 34mph for a little while on the hoods but no problems with my bike but at 20mph another time an my bike was like twitchy twice. Oh it's not a Pilot. But, what I'm saying is it could be due to maybe a small pebble on the road as well?

Did you shift weight?


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## cerveloguy (Jul 26, 2005)

It's probably one of two things:

1) Death wobble. Too difficult for me to explain in detail. Do a google.

2) Fork assymetry. Good paper about this on the Calfee site:

http://www.calfeedesign.com/forksymmetry.htm


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## rgojr2001 (Dec 8, 2006)

I had the same thing happen to my newly built Orbea. Turned out to be some loose spokes and a slightly loose headset. Have your LBS check it out.


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## grasslander (Mar 23, 2006)

Thanks for the responses folks.

OK got the bike back from the LBS. No real problems found. Checked true of the rims, the rear was in need of true and spoke tension, but not that bad.

I think I have a possible technique issue. I think I need to focus on weight distribution and get more weight on my feet versus the saddle. Maybe move back more and use more stomach muscle to insure I'm not influencing handle bar input. (Interesting read on death wobble and fork issues. The fork issue will take more testing than most LBS's I've been to could do.)

I will do some careful technique tests.


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