I have presta valves on my mountain bike now and only Presta valves can fit through the hole in the rim where the valve goes. If i want to start using Shrader valve tubes, because they are way more common and i can get them at Walmart, is it ok if i bore out the hole in my rim in order to get the Shrader valve to fit
You can get tubes with presta valves at places like Nashbar or Performance for about what schrader's cost at Walmart. Besides, the one time I got a tube at Walmart was a disaster. It split down a seam when I was 15 miles from home. Completely unpatchable, and I couldn't get anyone on the phone. A long walk. DON'T DRILL YOUR RIM. It would probably be OK, but you don't want to chance a weak spot on such an important part of your bike.
Your tube probably has a Schrader valve, like a automobile tire. You can get these in the auto department of most stores and of course at auto parts stores. You might pickup a little dirt. Look at the valve to see if it's dirty. If so, press the center of the valve with a small object (small screwdriver maybe). This will blast the dirt out with air from the tube. Of course, you will then need to pump up the tire a little. If the valve gets dirty and you simply pump air in when the tire is soft or flat, you may force dirt into the valve which could cause the valve to leak. Schrader valves are replaceable. You can get these (and the tool to remove them) at an auto parts store.
honestly, are you going through that many tubes that you're even entertaining this? and will you really save that much money getting tubes at wallywood? if you are blowing so many tubes, either you or your rim is at fault, and you need to go to your LBS to check it out. wallywood can't help you fix the wheel..
Probably not; compromising the rim that way is a recipe for disaster....stock up with a few tubes from a bike shop; WM tubes are total junk........
Yes you can. Many people have done so. Make sure you file the hole after drilling so you will not have any burrs. BTW most tubes come from China so if you want to put in walmart specials or from a reputable bike shop it will do the job. If you want to put presta valves again, then you can buy a grommet that reduces the hole size. If you have an expensive bike and want to keep it original, then I advise not to drill
