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Old 10-27-2010, 04:53 PM
42blue15 42blue15 is offline
Motorized Bicycle Elite Member
Join Date: Sep 2008
Location: St Louis metro, USA
Posts: 135
Default Re: High speed tires

Originally Posted by joabthebugman View Post
I am wanting to use my final for riding to work, about 15 miles

I see posts of other people who do this at speeds of up to 45 miles an hour

What tires are you using

A standard bicycle tire just doesn't seem like it could withstand the pressure of riding that far that hard
Bicycle tires regularly see brief speeds of 50-70 MPH and don't seem to have any issues from it.

A good athlete can pedal a regular bicycle at 30 MPH easily, and maybe 35 MPH for a brief time. So you can assume that pretty much any cheap bicycle tire around can handle 30 MPH just fine... I don't know but I would bet that any decent brand can take 45 MPH. (this assumes that they are properly inflated)

On a motorized bicycle, you might have a problem running high speeds for extended periods of time in extremely hot climates (if you live in a desert, that is).


The "problem" that tires have with high speeds is the heat, which is caused by internal friction of the sidewalls flexing as the tire rolls. The only way to reduce that is to use higher inflation pressures--BUT--then the bicycle must have GOOD suspension, because the tires will be too hard to absorb much bumps. Hard tires & high speeds will lead to frame and fork cracks very quickly.

There are no government speed ratings for bicycle tires in the US, so no bicycle tire manufacturer claims any speed rating.

If you did get bicycle tires DOT-rated, they would need to be rated to 75 MPH, as that's the rule for tires 3 inches wide or less. IIRC the test is increasing 5mph increments of 5 minutes each, and the tire must sustain the final speed for 10 minutes. I would be willing to bet that many bicycle tires could pass that test, but the testing and certification cost money, and there's very little calling for DOT-rated bicycle tires. Of all bicycle owners, very few build motorized bicycles, and of those, even fewer live in states where DOT-rated tires would make any difference in the bicycle's legal standing.
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