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TR2/3/3A Odometer gears for the early pot metal speedometer

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I wouldn't doubt it! My impression from talking to many gage shops is they like to keep their craft mysterious to the rest of us.
 
Guys, I found 3 guages yesterday, two of them, the odemeter does not work but the reset does. third one is good but little fast on speed. One of them with broken reset pinI drilled and put a longer reset rod from a TR4 on it. Works great, will do pictures when i a have a little more time. All three for sale

marv
 
After looking at mine in the dash, it looks like I have the spring loaded push rod in place. Just missing the knurled brass knob and shaft. Let me know what you have.
 
titanic said:
I made a few on my lathe from delrin rod.If my memory is correct, they are 20 teeth.
Click to expand...
I believe it varies, depending on which calibration speedo you have.
 
Randall-Agreed. I think the calibration changed with rear axle ratio and tire size (biased ply vs radials) on Tr3s. My experience is limited to a couple of TR3As and TR6, all of which had 20 tooth gears in the odometer. Since there is only about 3 gear sizes and they are used on MG and other British marques, it seems like the market would be big enough to justify the production of the gears.
Berry
 
Ok guys, heres what I have, first two speedos run fast , reset pins are good but odometers do not work. The last one on right runs okay, odometer works. Reset pin was broke off. I redrilled hole higher up then used reset stick from old TR4 guage. Works good.

marv image.jpgimage.jpgimage.jpg
 
titanic said:
Randall-Agreed. I think the calibration changed with rear axle ratio and tire size (biased ply vs radials) on Tr3s.
Click to expand...
There was also an early/late change point (when the tire size got larger) and of course kph vs mph. So something like 8 total different calibration numbers for TR2-3B, and 8 more for TR4-4A, and another 8 for TR5-6 (all according to an old chart I've got handy, originally posted to another forum by Chris K.)
But I don't know how many of those had unique tooth counts on the worm and/or worm gear. Tony's chart shows only 20, 25 and 32 teeth, with the other changes made at the ratchet wheel.
 
I am not sure when they changed to longer flexible odometer resets, and tin can speedos, but my 1961 tr3 had a tin can speedo and the longer flex rod. The one picture shows without the vinyl. The early tr3s I have seen have the shorter solid reset. However, I seen a ¼ longer version of the solid rest tube before and if you look at the very original black tr2 in Piggott’s book page 39 I believe there is a solid rest with a brass knob that is a fuzz longer for the tr2, but I am only surmising. So if anyone has picture of an original tr2 rest I would be curious.
 
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