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New vs. Old Style Transmission Tail Housings (side-by-sides)

269 Views 1 Reply 1 Participant Last post by  MattsAwesomeStuff
Probably no one will ever use this, but, I took pics and thought I'd share if anyone ever wants a reference as to how the old-style transmission compares with the new one. For those that don't know, the major difference (other than the housing) is that the older style speedometer pickup uses a right-angle gearbox that is fragile and expensive to replace. The newer style uses a straight gear (well, into a worm gear), and a different tail housing.

Shafts (new on top, partially disassembled). New has shorter splines on the output, a shorter neck, and the speedo gear that mounts to a hold in the shaft on a clip.
Household hardware Building Cylinder Metal Engineering

How the speedometer mounts:
Bicycle part Cylinder Auto part Nickel Gas

Here's a closeup of the speedo gears (blue and white nylon):
Automotive tire Household hardware Engineering Gas Auto part

New on the left, old on the right. New has a heavier spine, a gear selector pivot, and the different speedometer gear pickup:
Gas Nickel Bicycle part Auto part Font

Oil.. filler(?) is in a different place. Mounting feet have side braces. Also, notice the extraction pins (circles) on the new one. New ones are die-cast (mold injected) aluminum, old ones are sand-cast. Sand cast (mold is destroyed every time) is more expensive per item, and worse quality, but die-cast is much more expensive to set up.

Bottom. Looks like it's bolt-compatible, which makes sense:

Shifter pivot visible here:

Speedometer isn't just different arrangement, it's on the opposite side:
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One last one, as I hammed off the gears.

Old on top, new on bottom:

You can see that from tailshaft bearing and forward (the shiny spot), they're more or less identical.

Only difference I found was that the 2 grooves between the 4 gears is slightly deeper and more rotationally textured on the new one.
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