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VFD Gear ratio for side car use

Moderators: Curt!, Pa

Post Mon Dec 22, 2008 12:33 pm

Posts: 18
Location: Switzerland

What is a good gear ratio for a 34 VFD with side car? Current ratio: Motor sprocket 23T and transmission sprocket 28T (which is cool for solo but seems to be too long for side car use).
Any recommendation is appreciated :D

Post Sat Feb 28, 2009 8:03 am

Posts: 27
Location: Australia

I don't have exactly what you want, but since you have no replies yet, maybe this may help - then again, it may just add to the confusion :wink:


Post Mon Mar 16, 2009 4:45 pm

Posts: 87
Location: Finland, Europe
If I remember correctly, the original sidecar units exported to Finland had 17T on the motor sprocket. That's unnecessary low for modern roads. 28T is standard on the trans. On my 35VDS I have 23T for solo. I do not remember what sprocket was in use when I had the sidecar on last time. I have a 21T, that I plan to use when the sidecar is reinstalled. My guess is that 19-21T is ok if the motor is in good pulling shape. There is quite a difference when you have passenger and a lot of stuff. The hills get steeper somehow... You are not going to climb Die Jungfrau anyway. Well, getting up the Alps is one problem, getting down a loaded V-model with factory anti-lock brakes in one piece is another thing.

Theory: Everything is perfectly right, but it does not work.
Practice: It works but you do not know how.
We combined theory and practice: Nothing works and nobody knows why!

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