re drilling rim presta to schrader

gtd.

My Bike has Sun SOS 32 rims with Shimano M475 9m QR hubs that have Schrader valves

Just bought a used Specialized Enduro front wheel which is a Stout 20mm Hub and Sun SOS 32hole 28mm wide rim but Specialized branded.

This rim has a presta valve hole.

Could I drill out the rim to take a Schrader valve as I only have Schrader tubes and Schrader pumps

What size drill bit do I need?

nicklouse

8.5mm but make sure the land on the top surface of the rim is wide enough. you dont want the edges encroaching on the side walls.

Danlube

Yes you can BUT you risk weakening the integrity of the rim and say goodbye to any warranty.

Why dont you just buy presta tubes? have you checked to see if your pump can be converted to presta? also going presta and taking spare presta tubes on a ride can help out a mate with a flat. Presta can fit schrader rims in an emergency trip home.

gtd.

Once again thanks Nick

Compared the Presta drilled rim with the Scrader drilled rim and the "land" was the same width couldnt find a 8.5 so tried a new 8 and carefully drilled through the rim from where the rim tape sits first then looking to check the hole was centered after removing all traces or swarf then continued drilling the rest of the way through.

I tried a tube valve and it fitted through the 8mm hole with a little resistance so I'll just leave it as is fitted a spare tube and tyre to protect the rim till I get hold of some 20mm forks. hope I can get a 1,1/8" 2-step or dual air lyrik or similar soon

Dan its a second hand wheel so I have no warranty and its the same rim as my front and rear except its drilled for Presta instead of Schrader. just wanted a reasonably close match for my current wheel set for when I change from 9mm QR to 20mm forks

stu8975

What pump do you have, most mini pumps have been dual valve for a good few years now (just re-arrange the internals). or just use a valve converter and save drilling it.

gtd.

I've already drilled it and fitted a tyre and tube. seems totally fine and as the rim is idential to the other two except for the drilling I cant see it causing a problem as I dont do DH or AM.

I only use a cheap tesco mini pump as its unlikely to get stolen, and my frame dosent have bottle cage mounts so I attach it though the o-rings used to attach the downtube mounted crud catcher. the pump has rubber bits so it doesnt scratch the frame.

I just don't see the point of expensive mini pumps if I loose this one or it gets stolen its nice and cheap to replace. It puts air in my tyres and has a guage that works well enough what more could I want from a pump lol

stu8975

Who said anything about expensive pumps or it being stolen? Good mini pump will only set you back £10, I pointed out that mini pumps will do both valves...that inc your cheap £5 tesco one by simply turning the internals around.

Anonymous

He's already solved it though. Nothing wrong (generally) with drilling the rims out.

gtd.

ooh learn something every day just unscrewed the tip of my pump and turned it round.

Still prefer Schrader over Presta for convienience

gtd.

Unless you do something like that guy did with the expensive deep rimmed carbon rims I saw a pic of somewhere... he drilled them out then cut a chunk out of the rims he could fit a shorter stemmed schrader valve instead of a longer presta valve