MTFCA Forum

So, I patched a leaking tube on my TT rear tire and after I got it back together I found the metal valve stem was leaking. I tried to use some rubber cement and bike tire patch kit around the valve stem and it didn't help. So, I'm guessing I need either a new tube or new valve stem.

Langs has this stem that says it needs to be hot vulcanized, which I don't think I can do. https://www.modeltford.com/item/ST3-3/8.aspx

So I guess it's best to just buy a new tube?

I'd go with a new tube.

I intended to try to salvage metal stems from old vulcanized tubes for use in a traditional way, using original clamp washers. After tremendous effort, I was finally able to liberate the valve from the rubber and found the base of the stem, internal to the tube, was massive. It's interesting that yours is so small and without much support or stability. I can't begin to guess as to the age of the tube, but that failure appears to be a "when" and not "if" situation. Don't feel bad about it.

Stick on rubber valve stems will work as replacements, but modern types are too short/fat to use on clincher rim/felloe combinations.Truck tyre repair shops may have longer stick on stems. They may have to order them in, but they were available last time I needed some. They are about 3.5" long, which means the tyre/tube assembly needs to be fitted with both beads at the same time, so that the valve stem and tyre beads can be clamped in place on the rim. Trying to fit one side of the tyre and then trying to fit a 3.5" valve stem through the rim is fraught with difficulty.

Allan from down under.

What do you expect from a modern reproduction? An original would never have done that!

With that ridiculously tiny base stuck on the outside of the tube it's no wonder the stem popped off. The tube itself doesn't look torn, so I would keep the tube and install a T era metal stem. It has a much wider base that goes inside the tube, with a bridge washer and nut tightened on the outside to keep the works together.

After preparing the rubber, if you're thinking of using them, pour in a packet of balancing beads. Way easier to do it before the stem is installed.