presta to schreader

f2man

what size drill bit would I need to drill my rims to accept schreader valves

nicklouse

8.5mm

but make sure your rims can be drilled as some are not suitable for drilling.

f2man

Thanks how would I know if they can be drilled ?

f2man

Just checked - rims are Mavic X117 - would it be OK to drill these out

stubs

I have never examined a Mavic X117 rim but usually Mavic MTB rims are already drilled for Schraeder they come with a black plastic collar in the valve hole to fit Presta.

If you do drill out the rim make sure you get rid of the burrs before you fit the tyre and tube

delcol

all my mavic rims have the plastic cap,, remove the tyre and check,, it's easy to pop the plastic cap out,,,,,

rhyko7

i used an 8mm with a hand drill, tight fit but goes through just

stu8975

Buy a valve adapter if you don't like presta valves.