Hydrostatic Drive Diesel Motorcycle

Jeff Parker and Brian Okeefe work around hydraulic machinery everyday and have a knack for building some pretty interesting equipment. It turns out they're interested in motorcycles, too, so after spending some time in the shop, they wondered how they might combine their knowledge of hydraulics with their love of motorcycles and the bike you see here is one very cool answer. This bike belongs to Jeff who built it about 3 years ago but I never saw it until I was looking for information on diesels and ran across their website, Hydraulic Innovations. This bike has a custom built frame and mounts a Kubota 3 cylinder diesel engine but what makes the bike even more unique is the hydrostatic drive system, no belts, no chains, no gear drive transmission just hydraulic pumps and motors. Neat. You still control speed with a twist grip and there's a front brake lever on the right but the "clutch" lever actually opens a bypass valve to let hydraulic fluid recirculate instead of driving the bike. There is only one foot lever on the right side which has a sort of neutral position in the center, pushing it forward gets the bike in forward motion and pushing it to the rear actually can reverse the bike. Jeff says, theoretically it could go as fast in reverse as forward but he limited the speed to prevent things from getting out of hand. This is no garage queen either, Jeff rides it regularly. The bike gets about 65 to 70 mpg in normal riding but when he's out for a leisurely cruise, Jeff says he can easily get over 80 mpg, not bad for an 1123cc diesel engine in a 700 pound bike with another 200 pounds of rider. The fuel tank holds the diesel fuel

and there is a 2 gallon tank below it for hydraulic fluid. The bike will cover over 350 miles per fill up. He's been to Sturgis for 3 years now and the guys he rides with fill up 3 times to his one when they're on the road.
The bike itself looks pretty nice when you consider all of the mechanicals, pumps, hoses and everything else he had to deal with, not to mention the diesel engine. There have been other bikes with more conventional setups that don't look this good. Jeff's business partner is currently building a bike for himself and this one will have a lot of the hoses and fittings hidden within the frame to clean up the appearance a bit. Brian's bike will have a different hydraulic drive from the one Jeff used, but Jeff said he used the parts he had available at the time, collecting about 80 percent of the parts before starting the build. They have DVDs for sale on their web site that you can use to figure out how the drive system works and they provide part numbers if you want to try one of these on your own. If you aren't sure just what a hydrostatic drive is or how it works, you might want to get the DVD. Who knows, there may be a whole new group of diesel customs showing up out there, with hydrostatic drive, no less!
They have some photos of a few other projects, past and present on their website. They're worth checking out. This is excellent engineering from a couple of guys that just decided to do something different. I like it!