Like toPedal
had the same thing happen to my rain bike last year. all of the sudden it started getting shaky at higher speeds (+30mph) but as time went along it got worse and would start at about 22mph. i screwed with the front end a whole lot trying to nail down the culprit. (headset, front hub blahblahblah) it wasn't until the rear wheel was removed to do some hub work that a cracked in half dropout was found.
better check your rear dropout.......
________________________________
From: Max Kirchoff
To: obra@list.obra.org
Sent: Monday, February 2, 2009 11:38:57 AM
Subject: [OBRA Chat] Fork/Frame Wobble-shimmy ....HELP!
OBRAland,
Perhaps someone can give me some advice from experience or as a fitter.
I've got some bad wobble in my bike, specifically the frontend and mostly if i move weight (remove my hands) from the handlebars. But I can feel it in the bike slightly when on the bars as well. At certain speeds it gets real crazy without my hands on the bars.
Of course the simple answer is, "Don't take your hands off the bars, dummy!"
But I feel like I should investigate this as it might become a problem at higher speeds on distance rides.
My Setup:
1999 Schwinn Peloton
(probably not the culprit as alignment seems fine - also a 853 tubing bike, which should be tougher than my problem-free track bike tubes right?)
Schwinn Peloton stock aluminum fork
(kinda sketchy - at about 250lbs total, im pushing my luck with this fork i think - seems to have flex which I'm pretty sure it shouldn't but I don't normally run aluminum forks - possible problem cause)
Mavic Cosmos 9sp rear
(another possible candidate although I cannot find problems with it when its on the stand - mind you that's without 250lbs on it)
Xero 16spoke font
(rode this on my track bike previously, which felt solid as a rock, so not a suspect)
Fit note - I'm used to a much more aggresive position and this frame is like a LazyBoy comparitavley.
Could this just be a fit issue? Weight distrobution issue? Did I just put together some sort of frankenstein of parts that all have bad resonance when touching? Does the universe want me to give up riding bikes lighter than 20lbs? Do I just need to cough up for a new fork and see what happens?
Anyone got any low-costs tests or ideas?
Thanks.
Max Kirchoff
http://www.maxmeansmore.com
http://www.maxisnow.com