17 inch center style valve stem (TR-6) inner tube for 33 Plymouth help needed

[1935EB]

I am purchasing tires for my 1933 Plymouth project. It will use the wire wheels and an inner tube with the center valve stem (TR-6). Offset valve stems (TR-4) as used on Fords and Chevys' are available. The people at some large tire suppliers say that no one makes an automotive tube for 17 inch wheels and with center style valve stems.

My questions are these:

Could I use an offset style valve stem?

Some have suggested a motor cycle tube with center valve stem. The valve stem is smaller and shorter than a car. What problems might I encounter with these?

Your help is appreciated.

Chris

[Bob Scafani]

I just mounted several 18" tires using the offset stems. The same tubes are used on both 17/18 inch tires. The problem I had is that the stems are short and barely protrude through the rim and liner. I used the ones supplied by Lucas.

[ply33]

I've been using motorcycle tubes on my 33 Plymouth for several years now for the reasons you mention.

I've had no particular issues but the heavy duty ones seem to hold air better than the "standard" ones. With the previous set of tires I did not have the heavy duty ones and they lost a couple of pounds of pressure per week. The heavy duty ones I have with the current tires hold air pretty well. I still check every week out of habit but generally they don't need air. Just looked around for my last receipt to see exactly what I have in there and I can't find it.

There aren't that many motorcycles that use a tube that big so your local store may not stock them. Or if they stock them they may not stock five of them. So call first.

The hole in the rim is for the larger car tire stem. I use a fender washer to cover. IIRC I used a 1/4" ID washer and needed to drill it out slightly to fit the stem.

My car is filthy at the moment, so please pardon the dirt on the wheels.

[1935EB]

Thanks Bob and Todd,

The guy's at Lucas indicated to use metal stems as this could solve the problem of being too short etc.

An offset stem is only 5 degrees offset and I think they should work. That's why I am asking for folks who have done this.

That picture is worth a thousand words. This is a motorcycle tube with a metal stem. The washer is on the outside.

If you find the manufacturer please let us know. 550 in metric would be about 140 mm.

Chris

[Guest DodgeKCL]

Motorcycle tubes are the only way to go. They are made to a much higher standard than car tubes. A blowout on a bike can be lethal so I believe this is the reason they're made so much better. I discovered the reliability and quality of bike tubes during my riding days and brought them over to my antiques when I couldn't find any 17" tubes 35 years ago. Pick one slightly smaller than the 17" rim so it will fill out into the space. If you go too large the tube could fold over on itself,not a good thing. I have not had any problem with the stems duplicating the original style. They are black rubber with the standard Shraeder valve ,even running in inch thread, regardless of the tube being in metric. I put the correct period cap on,which is the one with the valve remover end, and have had no loss of air,except a a pound or two a year, for decades.

[ply33]

Duh. Should have looked in my car's maintenance folder in the file cabinet instead of the piles of unorganized stuff on my desk. The hand written number on there is the mileage I installed the tires and tubes, so ignore that.

[1935EB]

Ply33. So that is the motorcycle tube heavy duty that has the metal valve stem? Thanks for finding this. As to cluttered desks and workbenches we are all probably in the same boat.

DodgeKCL. Those were my thoughts as well on the robustness of motorcycle tubes. Also a motorcycle and rider is a lot of weight. Not half of what a car would weigh but still bikes are heavy. I gave up riding years ago when I got married and had children. For sentimental reasons I still keep the motorcycle rating on my drivers license.