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World Tour
04-28-06, 11:19 AM
Hi gang,
Y'know those spoke reflector things that bikes come with, usually one, opposite the tire valve?

Do they offset the weight of the tire valve? In other words do they act as a balancing weight?

It seems to me that without it, the wheel would be out of balance since it has a valve on one side and nothing to counteract that weight. I imagine it would be more noticeable as your speed goes up.

What'd'ya think?

VegasTriker
04-28-06, 04:31 PM
There are a lot of safety mandates placed on bike manufacturers by the federal government. I'm sure reflectors on wheels, pedals, and front and rear on the frame are one of those mandates. Not a bad idea if you have ever come across a kid riding a bike at night on an unlit street. Darn near invisible if there are no street lights. Often the only thing you see is the reflectors on the bike and the moving ones are ususally unmistakeable.

ppc
04-28-06, 04:55 PM
It seems to me that without it, the wheel would be out of balance since it has a valve on one side and nothing to counteract that weight. I imagine it would be more noticeable as your speed goes up.

A valve weighs only several grams, it is not noticeable at any speed reachable by a bike. A reflector is a bit heavier and can produce a detectable vibration if you turn the pedals very fast holding the wheel off the ground. In reality, neither the valve or a reflector can produce anything you can feel on the road. If you do feel something bouncy on the road at high speed, chances are it's your tire that's unbalanced.

sch
04-29-06, 12:48 AM
There is a separate thread on the mechanics forum about this with not much real info. My experience is that all bike wheel are unbalanced. This is most noticeable on the rear with the bike on a stand. If you crank up the rear wheel rpms the bike starts bobbing up and down in time with the rear wheel. It is not so noticeable on the front as it is hard to get the fr wheel moving faster than 10-15 rpm while the bike is on a stand. Although the stem is fairly light, the combo of stem and extra rubber around the stem makes for enough weight concentration for this to be noticeable on a bike on a stand. It is never noted by the rider will riding however. Some rims have a weight concentration where the rim is joined together, others dont.
Steve

JanMM
04-30-06, 08:18 PM
The real danger to bicyclists is traffic to the front and rear; I've read that wheel reflectors are only useful if you want to use your bike as a barricade. American bikes must be sold with them but they are easy to remove. Then, beef up front/rear visibility.