Bicycle Mechanics - What size drill bit to change Presta to Schraeder valve?

I want to standardize on inner tube type. What size drill bit do I use on my rim?
Thanks in advance!

11/16 drill bit. But I would go in stages and drill progressively bigger holes

11/32 is the one you want. Be sure to get all of the drilling chips and grit out of the inner chamber in the rim and remove any burrs from the edge of the hole. bk

A hand reamer works, too.

Yeah, chamfer that hole. I actually chamfer ALL the holes in the rim carefully, so I could get away without using rim tape. For low pressure tyres, it works very well.

11/16 drill bit. But I would go in stages and drill progressively bigger holes

11/16"?? I assume either that's a typo or an intentional joke. Thats almost 3/4" diameter and nearly as wide as most rims.

Round file by hand. A drill bit will bind and tear on relatively soft aluminum alloy rim metal.

check out: http://www.sheldonbrown.com/gloss_sa-o.html#schrader

If memory serves it's a 21/64th.

have done this a few times. I have found that a tapered hand reamer works best. You will also need to debur the hole afte to remove sharp edges. A drill bit larger that the hole works well.

I want to standardize on inner tube type. What size drill bit do I use on my rim?
Thanks in advance!

Some narrow or thin material wheels may be unsafe if you make the hole bigger. Presta tubes are everywhere. If the other wheel is drilled for Schrader you can just put a presta tube in it.

11/16 drill bit. But I would go in stages and drill progressively bigger holes

OH #@$%&!
Sorry about that. I meant 11/32. Do me a favor and never trust anything I say before noon.

Having done this several times, the advice of starting with the smallest bit possible and gradually working your way up is good.

Thanks to all!

A hand reamer works, too.

+1

http://www.biketoolsetc.com/index.cgi?id=122625992551&d=single&c=Tools&sc=Hand-Tools&tc=Hand-Reamers&item_id=HZ-K4B

Why is a better question.

Why is a better question.

Can't you read? The OP clearly stated he/she wants to standardize on Schrader. Don't make me go dutret on you.

Can't you read? The OP clearly stated he/she wants to standardize on Schrader. Don't make me go dutret on you.

I was pondering whether to drill out a seperate Shraeder hole in order to have the option of either valve type.

Are there covers out there for the non-used hole or might taping over work?

I was pondering whether to drill out a seperate Shraeder hole in order to have the option of either valve type.

Are there covers out there for the non-used hole or might taping over work?

You probably are aware of the fact that drilling two valveholes in the rim is not the best thing in terms of rim strength. That little warning out of the way; yes, there are such covers. They are called duct tape.

Why is a better question.

Most of my bikes uses 700c Schraeder tubes and gas stations uses Schraeder valve for their pumps too ( I use my bikes mainly for commuting to work). I know about the adapters, but its another thing to carry around.
I plan on opening up the existing valve hole, not drilling out another one on the rims.
Anyway, I hope that clears things up.

Thanks again!

EDIT: I just saw your most recent post about the adaptors....I just leave mine on.

My LBS installed Schrader adaptors onto my Presta valves for like $2.....I didn't have to drill any holes and it allows me to use my compressed air tank (which has no presta adaptor on it).

YMMV, but the adaptors seem like a MUCH better alternative to drilling your wheels...?

I have a couple of those adapters. Never liked to use them very much. Not a big problem, but a nuisance.