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Old 10-31-2009, 09:20 AM
lovehamr lovehamr is offline
Motorized Bicycle Member
Join Date: Oct 2009
Location: GA
Posts: 24
Default Re: High Speed Rear Blowouts

From what I understand, presta valves came about for two reasons; #1 was rim sizes were getting more narrow for high performance tires and the size of the schrader valve meant that the hole on the rim would compromise rim strength, this still holds true. Most rims that I see cracked are cracked at the valve stem hole, the larger the hole the weaker the rim all other things being equal. #2 is the positive seal. The only thing that keeps air in a schrader valve is a little spring, with a presta it's a screwed down seal. They don't leak.

As for the verbiage of "normal" or "regular" vs. "special" this is nothing more than semantics. If you ride a high performance bike then you use presta and all of your support gear is set for that valve type. If for some reason you have to use a schrader pump to fill a presta valve the $.99 adapter works fine, yes even with a gauge. It’s no big deal. If you ride a cruiser from China, uh, I mean Walmart, then it’s going to have schraders. But that goes hand in hand with all the other stone-age things that you get with that level of bike; like 1” threaded quill stems instead of 1.125” threadless which are much stronger, or 1 piece cranksets with cup and ball bottom brackets instead of modern large bearing 2 or 3 piece types. You only have to overhaul 1 of each before see the light and get yanked out of the dark ages. The list goes on and on but to many people that doesn’t matter and that’s cool as well. If you don’t use the bike’s crank to do anything more than start the motor then who cares. On the other hand, if you’re going to be using the pedals on a regular basis and plan to stress yourself and your bike, then looking into improvements that have been made in bikes since the 70s will pay off big.
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