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/2 to later engine/transmission conversion

lmo1131

New member
I'm just starting the information search for converting /2 to later drive train.

Anyone have a source for an overview?

Thanks.
 
Engine swap is the easy part. The harder part comes next. Integrating the existing /2 controls and switches with the electrical system of the implanted motor. Gets to be even more fun if the new motor is dual plugged. Oh, and don't forget integrating 6 volt stuff with 12 volt stuff...or just making EVERYTHING 12 volt. Then comes the really fun part with the transmission, gearbox, shaft and final drive. There are adaptor plates to connect the modern trans output flange to the /2 tranny, clutch and drive shaft, but now you are trying to put twice the design horsepower thru the /2 clutch, tranny, drive shaft and final drive. Not gonna last too long. Especially if you plan on adding a chair to the mix.

BTW, did I mention the fun of rewiring the WHOLE bike while fitting all the extra relays somewhere on the frame under the tank. Or an extra set of coils if dual plugged.

Well, now that your converted /2 is MUCH faster, comes the question of how to stop the damn thing !

Best advice is to locate a well done, sorted out conversion already built and tested by SOMEBODY ELSE if that is really want to do.

I've been riding my 62 R 75/6 conversion for about 30 years hooked to a Steib S 500. It was very well built, not by me, and still confuses me when I pull off the gas tank or look inside the headlight shell. But God is it fun to ride.

Friedle
 
Doesn't seem that difficult.

This would be my shopping list. A know good /5 or /6 motor and transmission. A /5 headlight complete, /5 wiring harness, / 5 handle bar controls, A /6 or LWB drive shaft with coupling bell/ splines and some patience. To install the motor you only need to spreed the frame rails slightly to drop it in with the transmission attached. You use the /2 swing arm and final drive but use the LWB or /6 drive shaft, you have to machine several thousands off the outside of the rear coupling bell /splines to get it to fit inside the /2 swing arm.

You would change your 6 volt bulbs to 12 volt and wire it just like a /5 or /6, you would have to be a little creative when you hide the relays and coils but it can be done quite nicely if you take your time.

You might have to alter the lower cross brace on the front end down tubes depending on the year and model of the front end. If you need more stopping power you can always lace you front rim onto a /6 disc brake hub and have a couple caliper mounts welded onto the earles fork swing arm, you might have to use a handle bar mounted master cylinder and alter the wiring a little to make it work
 
What about exhaust headers and mufflers? Do the later engine parts match up on the frame?
 
I am running /5 head pipes and /2 Hoske mufflers. The Hoske mufflers mount as they would on a /2. Sound nice too.

Friedle
 
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