Announcement

Collapse
No announcement yet.

valve core replacement

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    valve core replacement

    It looks like the valve stem on my front tire is loose, so I think it shoud be replaced.

    Does anybody know how to rip out the valve core and slot a new one in? What kind of parts/tools are needed? How finicky a job it is?

    I'm driving a 1980 GS 750 L with what I think is a tubeless tire (on account of not having spokes...)

    #2
    Re: valve core replacement

    Originally posted by Barbarian
    It looks like the valve stem on my front tire is loose, so I think it shoud be replaced.

    Does anybody know how to rip out the valve core and slot a new one in? What kind of parts/tools are needed? How finicky a job it is?

    I'm driving a 1980 GS 750 L with what I think is a tubeless tire (on account of not having spokes...)
    Is it a tube or tubeless tire((do they still make tube tires)) and in tubeless tires arent the usually done from the inside if the rim????

    Comment


      #3
      Valve core

      First issue is one of terminology. If you're asking how to replace the valve core, that's easy. If you mean the valve stem (assembly) that's a little harder, shouldn't be too tough, though. The valve core is the inner assembly that is the true valve. It's the same core that you'll find in car, truck, bicycle, or any other pneumatic tire valve stems. It screws out of the valve stem using a special tool that you can buy at any auto parts store for probably about $2.00. Some valve stem caps and some tire gauges have a core remover tool or capability incorporated.

      I've never worked with tubeless cycle wheels/tires, but I assume they're like car tires, which I've done lots of times. Most valve stems are basically rubber; after 'breaking the bead' (separating tire bead from the wheel) you just cut the inner portion of the valve off. Insert the new valve from inside the wheel, attach another special tool (screws on to the end of the valve stem), lube the stem with rubber lubricant, or soapy water, and pull the stem into place . Some valve stems have metal bodies and a rubber seat at the wheel; they have a threaded outer body and a nut that tightens down against the outside of the wheel to hold them in place. If you have this type, it should be obvious. I can't imagine the arrangement for a cycle being much different from this, but I'm sure there are others here who can clarify or correct me, if necessary.

      Another point. My '78 has alloy wheels, with tube type tires. I think I remember someone in another post stating that Suzuki started using tubeless tires/wheels in '82?? If your wheels are for tubeless tires, they should say "tubeless" somewhere on the wheel rim. You could very well have tube type tires on alloy wheels.

      Good luck .

      Comment


        #4
        Mine are tubeless. The valve stem passes through the rim from the outside and a nut is put on from the inside (with rubber seals in and out).
        I'm sure this could be done without removing the tire. If you can break the bead and get the tire pushed inward a little past the center of the rim it should be possible. Probably be easier with an extra pair of hands to hold the tire out of the way while you tighten the nut.

        Comment


          #5
          I got a little confused by the responses, until illumination hit.

          I'm pretty sure it's just the core that needs replacing. The little metal 'pin' isn't coming all the way back up, so I've got a slow leak.

          The stem on my tire (which is marked tube/tubeless) seems perfectly fine. It does have a metal nut holding it in place, but the leak seems to be coming only from the pin.

          I'll hit the auto parts store (again!) this afternoon and try to replace the core. If that works (and is as easy as screwing out the old one and screwing in a new one) great! Otherwise I'll have to take it to the shop to replace the stem... There's only so much work you can do in your apartment parking space!

          Comment


            #6
            $2 should buy a valve core removal tool. They just screw out (let the tire pressure down before removing: Despite much whistling as you unscrew it, there can still be considerable pressure wanting to fling that thing out). I check mine every few months, and it's not unusual to find they need snugging down. Take the valve core back to the auto parts store to find a match.

            Comment


              #7
              I ended up doing it right in the street in front of Cdn Tire (I was keeping pressure long enough to go from the West End to Burrard and Cornwall).

              total time: 45 seconds

              Comment


                #8
                Air Nozzles

                Originally posted by pjackson
                Mine are tubeless. The valve stem passes through the rim from the outside and a nut is put on from the inside (with rubber seals in and out).
                I'm sure this could be done without removing the tire. If you can break the bead and get the tire pushed inward a little past the center of the rim it should be possible. Probably be easier with an extra pair of hands to hold the tire out of the way while you tighten the nut.
                I haven't seen this posted yet, but I can't be the only one having the problem.

                The valve stems come straight through the mag rims of my '82 GS650GLZ. The openings of the valves point directly to the axles. I can fill the tires if a service station uses an air hose with the old offset style nozzle, but most "Kwikie Mart" type stations now have the coin operated air pumps with nozzles that point straight off the hose. So far, these have been impossible to maneuver onto the tire valve stems. There just isn't enough room between the rim and the axle to fit the hardware without crimping the rubber hose shut.

                Are there after-market products that either screw on to the valve stem providing an offset approach or something flexible to use while checking the tires?

                Drew

                Comment


                  #9
                  Re: Air Nozzles

                  Originally posted by Drew
                  Are there after-market products that either screw on to the valve stem providing an offset approach or something flexible to use while checking the tires?

                  Drew
                  Haven't seen anything yet on the cycle parts sites, but I searched Google with "valve stem adapter." Came up with this. Surely it's a standard size? Twelve bucks from a Guatemalan(!) BMW website. http://www.ogrismoto.com/accbmwgs.htm



                  It would have to come on and off easily. This doesn't look that big, but I wouldn't want it to throw the wheel out of balance if it were aligned improperly.

                  Drew

                  Comment


                    #10
                    Re: Air Nozzles

                    Duh. Look at the web address in the picture.

                    Drew

                    Comment


                      #11
                      If you get the cap style remover, you can screw it on to an old rubber valve and crimp the cap so it will not unscrew. Makes it a niftie tool

                      Comment


                        #12
                        slime

                        Barbarian, get the cap that can unscrew the core from the "Shrader valve" (thats what they are called) and check to see if the tire has been "slimed". Thats the stuff you can squeeze into a tire to fix or prevent flats. I have had some problems in the past with the little fibers in that stuff clogging the valve, and not letting it close all the way. The problem is once that suff is in there, every time you use the valve, some gets into the "core". It doesn't take much to keep the valve from sealing all the way.
                        Just another tip....

                        Comment


                          #13
                          Re: slime

                          Originally posted by Mark Harrop
                          ...check to see if the tire has been "slimed". Thats the stuff you can squeeze into a tire to fix or prevent flats. I have had some problems in the past with the little fibers in that stuff clogging the valve, and not letting it close all the way. The problem is once that suff is in there, every time you use the valve, some gets into the "core". It doesn't take much to keep the valve from sealing all the way.
                          That's the very stuff that failed to seal the apparently quite ordinary puncture in my brother in-law's front tire last weekend. It seemed to seal at about 15 psi, which helped us get it on the trailer, but it wouldn't keep enough air to ride the bike. I had to drive about 60 miles to pick up him, my sister, and his loaded Voyager. At least their week-long ride was ending, and they found me and my trailer at home! I haven't had an opportunity to ask him how the repair went.

                          I haven't used stuff of that kind since the 70s, and then never had the puncture necessary to test it. How well does it work when you'd otherwise be stuck on the road?

                          Comment

                          Working...
                          X