While I had the flywheel off, I see there'e a simple way to make adjustable timing. It may benefit from a couple degrees advance at higher rpms. Have to work on that in the near future.
Dave's 1962 Schwinn Briggs Bike
- Thread starter msrfan
- Start date
I always enjoy your detailed post, you share a lot...good for you I like that. Thats a beautiful bike, I always say i am done but always have one more build to complete thats on my mind.
Thanks Jeff. I like to share new ideas and capitalize on what I learn from all you other builders.
Hi kerry, all my photos of the jackshaft construction are on page 2 of this thread. Keep in mind that I mounted the shaft in a piece of 5'' box tubing that was laser cut to fit 2 common flange bearings that support the shaft. With the bearings mounted inboard, the 3D clutch just fits between them. I have 2 threads on this forum that illustrate the use of multi speed set ups. Here's a link to my 4 wheel project. The other one features my homemade 2 speed automatic, but I couldn't locate the thread. Anyway, I would like to see photos of your project when you can.
https://motorbicycling.com/threads/four-wheel-project.26605/
https://motorbicycling.com/threads/four-wheel-project.26605/
So I figured how I wanted to make the adjustable timing. I decided to make it look like a motorcycle gas tank mounted shifter. Cut some cardboard templates. Then made the parts out of steel and aluminum. Here's all the pieces it's going to take to make this work.
Luckily the housing where the crank comes out of the motor is round and concentric with the shaft. So I made that my pivot point. I had to go behind the flywheel and use the coil supports to hold the mechanism. Slotted holes provide the advance and retard of the timing. The coil mounts to that with standoffs. The gas tank has a wide flange around it that allowed me to clamp the gate for the lever. The lever pivot is on top of the head retained by 2 head bolts. Here's how the assembly works together.
A link from the lever to the pivot allows for easy timing changes. Retard a little for starting and advance on the fly as needed.
Came out real nice and looks cool.
Luckily the housing where the crank comes out of the motor is round and concentric with the shaft. So I made that my pivot point. I had to go behind the flywheel and use the coil supports to hold the mechanism. Slotted holes provide the advance and retard of the timing. The coil mounts to that with standoffs. The gas tank has a wide flange around it that allowed me to clamp the gate for the lever. The lever pivot is on top of the head retained by 2 head bolts. Here's how the assembly works together.
A link from the lever to the pivot allows for easy timing changes. Retard a little for starting and advance on the fly as needed.
Came out real nice and looks cool.
Way cool! This is adjustable on the fly I do understand. Not many motor bikes can boast that. The first motorcycles maybe I think I saw had this.
MS, you have surpassed all expectations...again! Adjustable timing that resembles a tank shift, over the top...can't wait to ride it.
Thanks guys, but it's not done yet. Dave came by and dropped off the primary belt drive guard. He had a guy vacuum form it over the wooden buck I made a few weeks ago and it came out dynamite. Heated and sucked down around my chunk of wood using chrome plastic. It doesn't get any better looking than that.
Just need to trim off the excess plastic and figure a way to mount it on the bike. This should be the finishing touch to the final pre-assembly.
Just need to trim off the excess plastic and figure a way to mount it on the bike. This should be the finishing touch to the final pre-assembly.
The mounting bracket is coming along nicely. I formed it over a piece of wood the same shape as the cover.
It will bolt to the kickstarter brace and the primary cover will screw to it top and bottom.
I had to notch the bottom of the cover in 2 places to clear the segment gear guide and the bottom of the brace.
I'm going to have my grandson weld 4 10-32 nuts to the inside to make it easy to attach the guard.
It will bolt to the kickstarter brace and the primary cover will screw to it top and bottom.
I had to notch the bottom of the cover in 2 places to clear the segment gear guide and the bottom of the brace.
I'm going to have my grandson weld 4 10-32 nuts to the inside to make it easy to attach the guard.
