Panhead sidecar gearing

[slamiste]

I'm sure this has been discussed many times already but the search feature in the forum isn't very helpful.

I'm going to be assembling a friends 49 Panhead. Part of the process involves installing a sidecar. What does the group recommend for motor sprocket size? The parts book I have only lists one counter shaft sprocket (35203-36). If this sprocket is available in other sizes what are the recommendations for the motor sprocket - counter shaft sprocket combinations for side car use?

Steve Slaminko

[Rubone]

Steve, the factory only made one transmission sprocket (it is tied to the speedometer ratio so they didn't mess with it). All overall gearing changes were done with the engine sprockets. The Service Manuals have specs on that stuff, and it didn't change much for decades. Depending on whether an EL or FL the gearing differs, also between a regular sidecar and a commercial use sidevan/package truck. Most SC were 22, but they can go down to 20 if needed.

[slamiste]

Thanks Robbie,

I should have checked the Service Manual before posting. Live and learn (hopefully).

Steve Slaminko

[kitabel]

This is the place to begin if the transmission is still using the original internal gear set, with 3.00:1 1st gear. If it has the "close ratio" 2.45:1 or 2.60:1 low gear (Andrews, etc. - not OEM for anything below the 1970s) the smaller engine sprocket will give the best performance in traffic.