65 FL Sprocket Combinations

[dukekleman]

Yes, I have that, Duke, but thanks for sending it along. Everybody says 22T on the motor sprocket (I ordered one online). The confusion, however, seems to be around what engine I have. This is an FL, not an FLH, and that table says 19T for the FL motor. With 19T not for sale anywhere, 22T is going to be my default setup to start.

John,

I understand you have the FL series engine package. This is a good thing in your situation. Meaning between the elevation air density and the elevation grade slopes you have, the lower compression FL is an advantage.
Sorting out the proper gear ratio with current parts availability is your solution as you are doing.

Here's something to consider:

OEM gearing for your scenario was the following:
Primary gear ratio: 19/37= 1.947-1
Secondary gear ratio: 22/51= 2.318-1
Overall ratio: 4.513-1

Your current Overall gear ratio: 3.282-1
My advice is that you do not use this ratio on your engine and drive line!

He's my advice to people/myself if it were a personal project. ( For many reasons)

Primary gear ratio: 22/37= 1.681-1
Secondary gear ratio: 20/51= 2.550-1
Overall ratio: 4.287-1

The 22T Engine and the 20T Transmission sprockets are currently available through Ted's Cycle V twin and others that sell parts through Ted's.

Part numbers:

19-0076 20T Transmission sprocket

19-0050 22T Engine sprocket

Hope this helps,

Duke Kleman

[Rubone]

I've been riding that sidecar since '79, started building it from parts in '77. One nice thing about sprocket availability for tapered shaft (pre '55) engines is the assortment of available sprockets, from 16 tooth to 25.
Keep in mind the standard trans sprocket at 22 teeth is what the speedo is calibrated to. Anything taller and your speed readings will be off. That is why with any engine sprocket size it still reads correctly.
As for the outfit I was a bit thinner then!!
All available sprockets..
DCP_5083.JPG

[JSB55]

He's my advice to people/myself if it were a personal project. ( For many reasons)

Primary gear ratio: 22/37= 1.681-1
Secondary gear ratio: 20/51= 2.550-1
Overall ratio: 4.287-1

Duke Kleman

Wow. You guys never cease to amaze me with some of the detailed replies I get to questions. Per several suggestions, I ordered a 22T for the motor sprocket, and a stock size 22T for the transmission, so that will be my starting point, but I'll keep this in mind. Between getting this all assembled and waiting for Spring, the first test ride is a couple months away.
John

[JSB55]

[QUOTE=Rubone;n330419]I've been riding that sidecar since '79, started building it from parts in '77. One nice thing about sprocket availability for tapered shaft (pre '55) engines is the assortment of available sprockets, from 16 tooth to 25.
Keep in mind the standard trans sprocket at 22 teeth is what the speedo is calibrated to. Anything taller and your speed readings will be off. That is why with any engine sprocket size it still reads correctly.


Just put a brand new Drag repop 22T on the transmission tonight, and the 22 for the motor is in the mail, but I'm keeping an eye out for smaller in case I need it.

I wish I'd gotten into the old stuff many years earlier. I envy your experience with them. Much more fun to work on and ride than the newer ones!