67134-62 DRIVE GEAR AND SHAFT

[panhead_kicker]

The 67134-62 DRIVE GEAR AND SHAFT I have are 13 teeth, and the gears appear to be made of a fiber material. (right)
I also have an unknown, very similar gear and shaft, except the gear is metal and meshes in the opposite direction.(left)
Would this be the earlier 67131-38?

67134-62 DRIVE GEAR AND SHAFT

IMG_E5213.JPG (179.88 KiB) Viewed 551 times

[nifty]

AFAIK all BT are RH helix like your steel, 62-67 BT were 13T like your steel, but usually supplied as an assembly crimped into housing.
So maybe your steel drive is the guts out of a BT unit?
Servi-car drives appear to be LH helix like your fibre -62.
A quick check on Google shows the early servicar -38 is also LH helix but coarser pitch & less teeth, but also supplied in housing.
https://www.cimarroncycleworks.com/Harl ... -11138-38-
So do servicars run special speedos?

Nifty

[panhead_kicker]

AFAIK all BT are RH helix like your steel, 62-67 BT were 13T like your steel, but usually supplied as an assembly crimped into housing.
So maybe your steel drive is the guts out of a BT unit?
Servi-car drives appear to be LH helix like your fibre -62.
A quick check on Google shows the early servicar -38 is also LH helix but coarser pitch & less teeth, but also supplied in housing.
https://www.cimarroncycleworks.com/Harl ... -11138-38-
So do servicars run special speedos?

Nifty

Thanks Nifty, I think you're right about the left being big twin. Like the servi , the gear and shaft for big twin was also offered as a separate part number. I found a couple service bulletins, No.462 in particular , dated May 15, 1962. describes how to visually identify between early , 1961, and 1962-up gears.
As far as I know , no difference between servi and bigtwin speedos... just between the gears to spin them.