Success: The Original Diesel Motorcycle

It all started with an idea.  Why not power a motorcycle with a diesel engine?  Many said it couldn’t be done and others wrote articles on why it would not work.  So, we began and set out to accomplish the impossible and prove the nay-sayers wrong.  Our journey had many twists and turns but, in the end, Success!!

We began with the frame, engine, and transmission.  Once we had the basic setup and driveline complete the rest would be from existing parts.  There are hundreds of headlights, taillight, and turn signal combinations so no point in caught up in the details.  First we needed to make a stable and working driveline that will take the power of the engine to the rear tire.  After that we could decide what tire was going to drive the motorcycle . . . the diesel motorcycle.

We began with frame selection.  How we wanted the motorcycle to ride and more importantly part availability.  We chose to stick with the mass availability of American aftermarket parts and bought a frame that would fit them.  This was no salvage build or donor bike.  We were bringing to life a ground up, black smoke diesel motorcycle built with red, white, and blue American ingenuity.  It needed comfort so a dual shock swingarm was decided on.  The frame needed to be comfortable for long rides, so we had forward controls.  With all these things checked off the list we continued.

After we had the frame, the power plant would be the next stop.  The decision was made to use a Yanmar v-twin diesel clone that was air cooled.  This would allow for an easier build without the need for a radiator.  The engine is a complete unit.  This reduces the need for an oil tank and added oil lines.  The engine was designed with a simple 4-bolt pattern on the bottom.  This further added to easy installation by welding a solid plate on the bottom of the frame.  Now engine and mounting were checked off the list.

Next, was the primary drive, transmission, and final drive to finish up the driveline of the diesel motorcycle.  We chose to use an Ultima 6 speed transmission and final chain drive.  For the primary drive we use a belt drive.  These options made sure to allow easy installation and low maintenance.  Once the driveline was finalized the gear ratios were figured out.  Since the diesel engine has a 3600 rpm red line we had to calculate the primary and final gear ratios to be different than stock gasoline motorcycles.  This was not an issue as the engine has greater torque at low rpms to power through the lower gear ratios.

Once the powerplant and driveline were complete we set out to complete the rest of the diesel motorcycle.  We chose a large 7-gallon fuel tank, large round turn signals, and a yellow paint job.  The main reason is to be visible on the road.  With front and rear disc brakes stopping is not an issue.  We added a nice sized seat for comfort.  The diesel motorcycle came roaring to life and we were ready to throw a leg over and take it for a test ride.  The last addition to complete the diesel motorcycle was  a turbo.  YES, this is now a turbo diesel motorcycle rolling down the road. 

The results are awesome!  When getting on the road the diesel motorcycle can lay down black smoke!!  It has no problem keeping up with traffic and handles smoothly.  The diesel motorcycle has a low center of gravity.  It feels great turning and rides comfortably with the dual shock swing arm.  It is a great prototype and has proven to all that the nay-sayers were wrong.  Now that this is compete we will continue to ride it as we begin our journey to produce “Inline 3” and fill orders.

Will you join us?

Project Details

Important Points