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Old October 24th 2005, 03:42
jeremy_rutman jeremy_rutman is offline
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Join Date: Oct 2005
Posts: 8
Thanks Bruce2 thats exactly the kind of info I need.

My motor has 2500rpm nominal (before torque starts to fall) and 8000rpm max.
100km/hr (~60mph) corresponds to 775wheel revolutions/minute for 68cm diameter wheels.
so I should reduce by factor of ~3 or 4 to get 100km/hr before losing any torque.
If I understand right from http://www.geocities.com/vwtyp181/181_3-2.htm
the diff. has a reduction of 3.8 or 4.3 depending on year so I am ok to just connect motor straight into diff, no other gear required.

Given this and inefficiency of any gear, I'd like to avoid them altogether so I was thinking to remove the gearshift housing and gear carrier (parts 45 and 52 on the attached pic #1), and all the kishkes you mentioned, and attach the motor shaft to whatever sticks out of the differential.
(2nd attached pic)
I can make a doohickey to mount the motor onto the bolt holes that the gear carrier normally attaches to...if I had the blueprints I could plan it now before spending a dime or even a red cent

The reverse is a good idea, already built into the motor controller.

Quote:
Originally Posted by Bruce2
What max rpm does your motor turn?

You are going to need to retain at least one gear since the input shaft of the trans is not connected to the output shaft. It will probably be 4th gear.

You can probably leave out the shift rod, the hockey stick, internal shift rods, forks, 1st, 2nd and 3rd gears. The trans would need 2 custom spacers to take up the distance left from leaving out those other gears.

For reverse, have a big switch on the dash to reverse the polarity of the motor instead of switching the gear. That way the trans will always be in gear. No clutch required.
Attached Images
File Type: jpg transmission3 detail.jpg (19.0 KB, 27 views)
File Type: jpg chop gear (not bell) after.jpg (37.0 KB, 25 views)
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