Tire Valve question

[Breakneck]

I have a Linhai 300 that I would like to replace the tire valve stems on.
Reportedly they fail and fail abruptly for some people.

Mine are in good shape right now but I'd like to change them when I want to and not when I have to. I also don't want to chance an accident when it does happen.

My question is I see different sizes of these available on some websites.

How do I know what size to get? Does this really matter?

I can't find anything about this and have searched enough.

[cheapeto]

[http://scootdawg.proboards.com/thread/48156]

If you follow the Kurvygirl link, go to the 2nd page where the 2 for $10.00 stems are at.

[kz1000st]

I can only relate my experience on that issue. Six years ago when I first joined this forum I read about valve failure and I was skeptical but I took precautions. Each Spring I wipe my valves with Armor All and have had zero trouble. A Linhai is above the riff-raff, run of the mill Chinese scooter in terms of components and most likely has valves manufactured in China that go on Yamahas since Linhai is heavily associated with them. I would think if you wiped the valves with Armor All, kept an eye out for cracks and watched your tire pressures they will last a good long time.

You don't think the Japanese are making their own valves anymore do you? Hondas are made in Thailand, the Suzuki GW-250 in China and the Kawasaki J300 scooter is built in Taiwan.