I’ve got nice new aero wheels which come with the valve extenders to thread permanently over the presta valve head. I unscrew the locking head on the valve before I put the extender on but it would appear that over the course of a ride the locking head screws itself back in, so when I come to top up the air in the tyres it won’t go in. I then have to unscrew the extender and fiddle around with a pin / paper clip to unscrew the valve screw. In the process I have to sometimes renew an o-ring for the extender to seal, and they could be awkward to get hold of…so the bottom line is:
Has anyone ever chopped off the locking screw to keep the valve permanently able to take air? Will my air leak out faster??
Instead, get a valve extender that allows you to remove the core from the tire and insert it into the valve extender. That way you are just dealing with a long valve basically. You can get them at the LBS, but I’ve been getting them for about 5 bucks online. Here is an example from Tri-Sports.com site: http://tri-sports.com/devaex.html
Should have mentioned… I use these for my race wheels (tubies). For clinchers you can just get the extra long valve tubes. Anywhere from 48 - 80mm lately.
I think the Tufo extenders (or similar) are the way to go. Screw the valve core out, install the extender on the stem and reinstall the valve core on the top of the extender. Everything works like it did before without all of the hassles you describe.
I’ll hang on to the extenders until I run out of tubes / o-rings then switch to the long valves…shame a bit though as the extenders are nice brass ones which the track pump push fits onto - I find the rubber grommet on my pump head gets wrecked pretty quickly with pushing onto threaded barrels. Still it’s replaceable and is a small(er) price to pay!!
Will now have to figure out how to prevent long valves which have a smaller o/d from rattling and clonking in the clearance hole in the wheel…sheesh