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TR2/3/3A Odometer resets for TR2-4A

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T

titanic

Jedi Warrior
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A recent thread on odometer gears&resets had me wondering if there is enough demand for the reset knob/shafts to warrant making some. It looks like they come in several varieties-different lengths and type of knurl on the knobs. There might be a problem in sourcing the spiral wound cable used on some. A generic bicycle or choke cable housing is close.
Anyway, how about a show of hands of anyone interested. Price should be no more than $20.
Berry
 
Yes, I think there would be interest. I have half a dozed speedometers that are lacking the knob and cable assy. Somebody must be making these already as they are sometimes replaced by instrument restorers. There is at least one supplier of same for old British motorcycles with Smiths speedometers. (9 something British Pounds. Seller njavery eBay UK) I know there are several types but I bought a used motorcycle reset knob that fit a TR3A speedo with very little modification.
Tom
 
As an emergency solution you can always use that piece of choke sheath (or bicycle brake sheath) and one of those grab bolts found on the back of the PC boxes.

JesĂşs
 

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Yeah, I once made one from the shaft of a flint lighter from a Coleman lantern. I agree, a real part would be better.

I used to have a source for these but can neither recall nor find who or where that was.
 
The missing reset shaft is only part of the problem. The main reason they get separated from the speedometer is the 1 mm hole in the 3mm internal shaft gets broken out. That hole accommodates a 0-80 machine screw in the head of the reset shaft. The hole isn't threaded so the connection is a loose fit. Years of "resetting" the trip meter eventually "breaks" the connection and out falls the reset shaft, never to be seen or heard from again. I've had mixed results re-drilling the hole in the internal shaft. First of all, it needs to be removed from the speedo unit. Next, if you move the new hole too far up the shaft, you won't have enough room to re-attach the screw in the new hole. The alternative is to build a new internal shaft. Not that difficult if you have the tools but you still need a new external shaft. (For the TR2-3B, they come in 2 lengths depending on which type of speedo case you have ) The 4 and 4A lengths may be different still)
Frank
 
Frank-I agree the problem seems to the the small dia. internal shaft that is weakened by hole for the set screw. Thinking back, I remember the reset shaft was missing in a Tr3 that I purchased in 1962 (2 years old) and shaft was broken at cross hole. I was wondering if just filing a small flat on the internal shaft together with a larger external shaft and set screw might be a better solution. But of course, it wouldn't be original.
Thanks for the sketches in your previous posting. It helped me identify the shaft in my original posting-it was a short shaft version that had shed the knob from the splined end.
It looks like Jesus came up with a workable replacement from available parts.
Berry
 
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Agree on snapping at the hole. I've got several of them, and they are all like that. I "repaired" mine by drilling an old chrome/brass standoff to be a very snug fit on the original shaft, and drilling a smaller cross hole just big enough to take a piece of safety wire (.043" I think). The hole is very close to the surface of the case, so I used needle nose pliers to insert and bend the safety wire. Added some slots on each of the flats at the other end; the result looks quite nice (although certainly not like the original). Don't know how long it will last, but it seems good after a few years of resetting the trip meter at every tank of gas.

When it breaks, I make a new shaft.
 
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