Slow Leak in Front Tire

[Guest goose2241]

I developed a slow leak in the front tire of my Ballabio. Last week almost to the day, put a new Metzler on the front. This morning I rode the bike to work. It was standing up in the corners. I checked the air pressure and it was 13 psi. What are the odds of me catching another slow leak on a tire with 69 miles on it. Could it be a bad valve? Could it be a bent rim? I doubt they didn't inflate the tire at the dealership.

 

Any ideas?

[Guest ratchethack]

G2241, it's more'n likely a leaking stem valve. You can check it quickly enough with soapy water on the valve stem by looking for bubbles. If you find a leak, I'd take it to the place (assuming you had it done) that mounted the tire and have 'em put in a new Schraeder valve. It's the internal part of the stem and it threads out & back in. It takes all of a couple minutes.

 

PLEASE don't ride over there with anything less than 30 lbs in y'er front tire!

[Guest goose2241]

I'll find out soon enough. Going there on Friday. With at least 30 lbs of pressure

[belfastguzzi]

It could very well be a split valve stem (rather than a faulty valve). If you search the forum you will find that this has caused slow leaks for a number of people here. It's not clear if all V.11s wheels were produced with rubbish valve stem metal or if different materials were used at different times or for different countries. If you don't have stainless steel valves then change to them for a long-term fix.

 

I had this problem on a Ducati, which uses the same light-weight valve stems that inevitably split and leak. The V.11 suffered a more dramatic failure when the nut (same light material) that secures the valve to the rim split. The rear tyre lost pressure as air leaked past the valve and then it dramatically lost air, shape, steerability etc when the valve dropped from the rim into the tyre.

 

Be careful about just fitting a new inner valve, if the problem actually is that you need to get 'proper steel' valve stems.

[Guzzirider]

I had the same problem, and even after changing the valve it still leaked. The problem? Turned out that the aftermarket valve cover I had recently fitted was too short and pressing on the valve making it leak!

[Guest ratchethack]

If y'er tire man is doing his job properly, after mounting a new tire, as a matter of course, he will throw a quick splash o' that magic elixir o' th' Tire Man, Ru-Glyde on the stem after every tire change and watch for leaks, which will show up as bubbles. Ru-Glyde is the stuff they use on the bead of the tire to ease mounting and seating of the beads. It's also what forms that putrid green pool on the floor by the tire-changing machine. The 2-second test will reveal a bad stem as easily as a bad valve. It can save countless hours of grief down the road. . . . .

[Guest goose2241]

Thanks for the reply guys. I put some soapy water on it and sure enough came the bubbles. And as Murphy's law goes, I noticed the nut was a little lose. I tightened it a little and the valve started to hiss even more. I'm now roughly losing 5 pounds of air every half hour. Based on that calculation and some stops to get air and along the way, I should make it to the dealership. Knock on wood.

[belfastguzzi]

some stops to get air and along the way, I should make it to the dealership. Knock on wood.

have you got a footpump that you could bring with you?