[moschika]

any ideas on how to expand the presta valve hole to fit a schrader valve? do i just file slowly around the edges until it's wide enough?

any ideas would be appreciated, thanks.

 

[Dave_Stohler]

Sure, either that, or just get a [email protected]$$ drill bit. When the rim fails at the hole you enlarged, where the rim was weakened, console yourself as you walk home that it really was worth the $1/tube you saved by switching to cheapo schrader tubes.

 

[Spoke Wrench]

any ideas on how to expand the presta valve hole to fit a schrader valve? do i just file slowly around the edges until it's wide enough?

any ideas would be appreciated, thanks.

Actually, bike shops have a reamer that's made just for that purpose. I've reamed out a bumch of rims with no failures at all that I'm aware of.

 

[divve]

A stepped cone drill bit will work very well too.

 

[plus_vite]

A 1/4" drill bit will do this easily...

any ideas on how to expand the presta valve hole to fit a schrader valve? do i just file slowly around the edges until it's wide enough?

any ideas would be appreciated, thanks.

...although I don't really understand why you can't just go with presta tubes, but I won't judge.

Reading on the subject of rim strength tells me that a slightly larger hole won't seriously compromise the strength of the rim. The same sources also say that the main advantage of the presta valve is to maximize rim strength, so there you go.

Of course, the valve hole is the weakest part of the rim, so you will get a chance to put theory into practice. Good luck!

-PV

 

[Cory]

Used to be common on MBs--usually no problem

Rack him up, Dave--where's he get the guts to ask a question you think is dumb?
Reaming out the holes used to be common in the early days of mountain biking, because Presta tubes were hard to find. If your rim was drilled for them, and the only spares your friends were carrying (or that you could find in the sporting goods store) were schrader, you were screwed. As somebody else said, there's a reamer made just for that, or you could use a drill bit that JUST fits into a schrader hole (I forget the size, but Home Depot will have it). I've done several of them with no trouble.

 

[moschika]

why presta to schrader? you ask? (climbing off my rack)

so i can run extra heavy duty tubes on my commuter that only seem to come with schrader valves. I already have one rim that came with a schrader hole, the other didn't. the one that didn't seems to flat more because of the thinner tubes that only fit it. i carry a spare presta tube so it's really no big deal but it would be nice to have the extra bit of protection already in the tire. i can on and on but see no need.

It's not like i'm switching, i'm just looking for consistancy.

thanks for the tips