My Refinements

I've been busy refining the controls of this bike. I have primed and painted all the raw steel. I have also repositioned the clutch lever to the top bar. The lever is attached using a bolt welded to the lever. The bolt threads into a coupling nut welded to a mount made from a 5" piece of 1 1/2 inch wide steel channel.  I could have used a piece of steel tubing and solid round bar for a pivot point but I wanted to minimize the width of that pivot point and didn't want the hassle/danger of a cotter pin to keep the rod from sliding out and the chance it could snag clothing or open skin.  The threads of the coupling nut hold the bolt in place while still allowing the lever to pivot because it isn't threaded all the way in.

Closeup of pivot point w/bolt welded to lever and
coupling nut welded to mount

The steel channel is placed with the channel upside down, which creates a tunnel for the brake and shifter cables routed across the top of the top tube. This assembly is attached to the top tube with hose clamps. Bicycle inner tube is wrapped around the top tube before hose clamping the lever assembly to keep everything in place and protect the finish.

The lever and spring now pull to engage the clutch rather than push to disengage it. With this new set-up, the pivot point of the clutch lever acts as a fulcrum in conjunction with the spring tension, keeping the clutch engaged until the rider flips it back. I also wrapped a folded section of bicycle inner tube at each attachment point of the engine mount to the frame to minimize engine vibration.

Clutch engaged

Clutch disengaged

The throttle control was cannibalized off another bike and works well with a compression spring on the engine side to reduce speed when the rider let's off the lever.

Throttle lever (under handlebar)

Engine mount for throttle cable with return spring

The v-belt was slipping a bit on the driven pulley.  I used three pieces of one foot long 3M anti-slip tape and applied it to the surface of the driven pulley.  Great traction now!  I'm still breaking in the engine but was able to hit 33 mph with this set up, measured by my GPS.

3M non-slip tape

Last thing I did was install a bottle holder to keep a stainless steel bottle of gasoline as my reserve tank.  The tank on the engine is rated at 1/3 a gallon.  I've yet to figure my mileage, so I'm not sure how far I can go before I'll need more fuel.  

Gasoline reserves (bottle donated by my daughter)