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bikin' Ed · 11-24-2012, 10:48 PM

Another thing for all of us to remember is that rubber valve stems were really not designed for anything over 40 psi. Anthing in the range that you mention should be a brass stem.

Passenger car wheels and most light truck valve holes are 1/2 inch diam while the brass valves need 5/8 diam holes. Steel wheels are easily drilled out, mag type..... not so much.

If you have a mag type wheel and are running that type of pressure my guess would be that you have a bead leak. As the weather changes the tire and wheel do not expand/contract at the same rate....dirt finds its way in...the wheel corrodes. If you have a stem or bead leak, fix a flat won't help. And yes, tire techs HATE to deal with your wheels after you've used it.

11-24-2012, 10:48 PM	#4 (permalink)
bikin' Ed Master EcoModder Join Date: Jul 2008 Location: Tallmadge, OH Posts: 313 Thanks: 6 Thanked 26 Times in 21 Posts	Rubber valve stem Another thing for all of us to remember is that rubber valve stems were really not designed for anything over 40 psi. Anthing in the range that you mention should be a brass stem. Passenger car wheels and most light truck valve holes are 1/2 inch diam while the brass valves need 5/8 diam holes. Steel wheels are easily drilled out, mag type..... not so much. If you have a mag type wheel and are running that type of pressure my guess would be that you have a bead leak. As the weather changes the tire and wheel do not expand/contract at the same rate....dirt finds its way in...the wheel corrodes. If you have a stem or bead leak, fix a flat won't help. And yes, tire techs HATE to deal with your wheels after you've used it.