Q: What happens if you screw the plastic cap on a presta valve..
05-12-14, 10:18 AM
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Q: What happens if you screw the plastic cap on a presta valve..
Question: What happens if you screw the plastic cap on a presta valve without closing the stem completely?
Has anyone done this?
Has anyone done this?
05-12-14, 10:35 AM
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Nope, they're not carbon rims (whew!!!) they're Bontrager Nebula 32-hole rims
I'm Just looking for a possible explanation for a weird occurrence. This crossed my mind as a possibility.
I'm Just looking for a possible explanation for a weird occurrence. This crossed my mind as a possibility.
05-12-14, 11:00 AM
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Bontrager is just code for Trek so even if they're not carbon they'll likely asplode. Just be safe and throw that little plastic cap away!
05-12-14, 11:02 AM
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I think my garage is a natural habitat for bike gnomes, who like to mess with bicycles when no one is around and/or the lights are out.
05-12-14, 11:05 AM
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It's hard to tell if you're serious.. how would the rim explode? The pressure point for the air doesn't change. It would still be coming out of the valve. I think it could blow the little plastic cap off.. possibly?
05-12-14, 11:10 AM
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It's physics. Don't worry though so long as you don't have crabon fibber wheels and you replace your trek rims you won't have to worry about asplosions.
05-12-14, 11:19 AM
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apocryphal sobriquet
I suppose it's possible the cap could depress the valve and let out the air.
05-12-14, 11:21 AM
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Try it and see. Depending on clearance, it is possible the cap would push down & release air. The manufacturer should make the caps tall enough to prevent it, but who knows ?
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05-12-14, 11:40 AM
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Possible, you think?
05-12-14, 11:45 AM
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Now that you know the evils of the plastic cap, you can pump up your tire without it and see what happens.
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05-12-14, 12:44 PM
#16
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Pumped it up the next morning and it was fine.
05-12-14, 09:06 PM
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I guess I've been left behind, again. I always pump up my tires with the cap off.
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05-13-14, 05:20 AM
#20
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Just a point of information. The plastic cap's only purpose is to protect the valve from puncturing the tube during shipping and while it's in storage It looks good on our bikes but once the tube is installed, the valve cap serves no purpose and is not necessary.
05-13-14, 06:11 AM
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05-13-14, 07:48 AM
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05-13-14, 09:30 AM
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The caps also protect against idiots at your workplace who for some unknown reason decide to break off the tops of presta valves. I now keep the caps on my commuter bike.
