Handlebars shake?
12-22-06, 07:50 PM
#1
DavidARay@gmail.com
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Handlebars shake?
Okay I have been using this bike for a while. I changed out the bars with north road bars from drop bars. I put a rack on the back and I was carrying a 20 pound load. The other day I was riding for the first time since the transformation from a road bike to a touring bike. I was going at 14 mph and when I lifted my hands off the handlebars to get some water I notice the bars were shaking and they got worse the faster I went. I got to 24 mph without hands and tehy were still shaking bad, but not bad enough to wipe me out. What could it be? the rim is straight, the bars are even with weight, I tried a few things, any ideas?
12-22-06, 08:31 PM
#2
feros ferio
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I had the same problem with my first Capo when commuting home from UCLA with a Pletscher rack loaded with textbooks. Front wheel oscillation has been discussed extensively in various bicycle forums, and it appears to be related to frame stiffness, geometry, load, bearings (headset or front wheel) and even REAR wheel balance and/or alignment. Transferring some of your load to a front handlebar bag or a backpack may give you some relief.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
12-22-06, 08:58 PM
#3
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Try moving one hand to the center of your handlebars, and hold it very very loosely, while grabbing the toptube with your otherhand.
If you transfer weight to the toptube, you'll often stop the shimmy right then. Also, if you loosen your grip on the 'bars, that will often help too.
If you transfer weight to the toptube, you'll often stop the shimmy right then. Also, if you loosen your grip on the 'bars, that will often help too.
12-22-06, 09:10 PM
#4
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Pick up the book Bicycling Science by David Gordon Wilson. It explains why this happens. It's complex geometry and metallurgy etc.. as John E said.
12-22-06, 09:19 PM
#5
hello
My tourer/commuter mtb conversion's front end shook as you described, regardless of the load I was carrying. I was running Continental Town & Countries and when I switched tires to Panaracer street slicks the shaking stopped.
12-22-06, 11:55 PM
#6
Senior Member
Originally Posted by DavidARayJaxNC
Okay I have been using this bike for a while. I changed out the bars with north road bars from drop bars. I put a rack on the back and I was carrying a 20 pound load. The other day I was riding for the first time since the transformation from a road bike to a touring bike. I was going at 14 mph and when I lifted my hands off the handlebars to get some water I notice the bars were shaking and they got worse the faster I went. I got to 24 mph without hands and tehy were still shaking bad, but not bad enough to wipe me out. What could it be? the rim is straight, the bars are even with weight, I tried a few things, any ideas?
In addition, you might just check the preload on the headset bearings, as it may be looser than it should be. If all other things are equal, and the bike didn't shimmy before, a change in handlebars is unlikely to have changed the dynamics of the bike.
