Curious what most do with the nut, whether removing it, snugging it against the cap or lightly tightened against rim. I've done all the above w/my road bicycle and dealt with torn tubes at the stem from daily inflation abuse over time, rattling loose nut when not tight against something or tight against the cap. Doing the latter I feel like I'de let dirt and debris enter the stem hole though noted a past post re: seals of some sort though an O-ring might suffice. As stock the nut is secured to the rim and I do that on my bikes since when I need to pump them I'm not destrying the tube/stem interface. With rim locks on the Husky's wheels what is recommended. Considering getting some o-rings so I have a slight play for the stem to float a bit but enough to keep the nut secure.
I ditch the outer nut and use these instead: http://www.rockymountainatvmc.com/p/43/-/171/726/-/22204/Tusk-Rubber-Valve-Support-Seal Just like Honda does from the factory.
no a chop or dig or anything but...been riding moto and pedal bikes for 40 years, never torn a stem out of a tube, even while riding flats unless i really wad it up w/o a good rimlock. i still dont know what peeps are talking about with that. ive seen some come in cocked and crooked from impropper install and braking while running flat etc...but ive never ripped a stem off a tube myself that wasnt already shredded from running flat for miles, certainly not on a pedal bike, esp a roadie! on the motos if i dont have a valve mud guard (Honda makes nice ones!) on the stem i'll nut both sides of the rim with a duct tape strip that seals the stem of the valve and rim lock pretty good. and, powder the tubes. if you nut over the Honda valve mud gaurd on the valve and lock stems it's pretty weather tight. pedal bikes with presta get zippo- faster to change a tube in a race that way. my mtn bike have tubelss now. roadie gets a tube, maybe an o-ring/nut around the stem if its sloppy. on a tube type rim water will get in from a zillion places. this rots the valve then its easy to kabloowey it.... on high pressure stuff they seal fairly well at the valve/rim in dry conditions [w/o the inner nut]. there's a 110 psi in there it should!
Up against the cap, personally do not worry about dirt/crud getting in there. I've ripped a few tubes, at super low pressures (under 8psi) with trials tires. I'm in a new location now and standard knobbies at standard pressures work much better than trials tires - but still have the nut against the cap.
Push and pull a rubber stem enough with a silca presta adapter, chafing against the sometimes sharp edges of many wheels can do what I said and flat. Without a nut to hold the stem or you holding it with your fngers when filling can take some abuse and fail in time. Even with taping, or not quite enough tape. I use a different screw on chuck now so I really don't need the nut. And motorcycle stems are reinforced better at the inside rim interface. Basically more a potential sealing issue and having something of resistance to a chuck or air guage on the stem. The Honda seal sounds good and that is the info I was seeking. Thanks! *
I use the Honda rubber valve stem thing and a plastic valve stem cap. i have spun a tire during a motorcross race and it will pull stem in pulling off cap and not go flat i also bevel hole a bit. when you race its all about making it to the finish.
