Ernie at RFD won't sell his Yamaha 4 cylinder (YG4) conversion, it's pretty much a static display. He ran into too many issues which impact safety, including electrical glitches resulting in sudden engine power reductions to idle, and failed clutches. He beefed up the clutch, but I don't think he ever eliminated the electrical gremlin completely. He decided that too much time was involved in making the conversion and that he couldnt' make any money doing it. Bottom line, forget Ernie and RFD, they have abandoned the Yamaha conversions for the time being. I am going to change his mind on that very shortly, however, and sell him ours.
The Yamaha 3 cylinder (YG3) conversion that Todd does out of Colorado has also suffered numerous problems since inception - including catastrophic clutch failures and cracked/broken exhausts, problems all related to the design. They build a complete box frame outside of, and surrounding, the engine, which introduces all kinds of strange vibration combination possibilities which can easily result in migraine headaches. Supposedly they have the problems sorted out, but the design is still not very good for several reasons: it is complex, difficult to install, unnecessarily heavy, and very expensive.
These issues led us to abandon both concepts completely and start from scratch with a next gen design which avoided all of the mistakes and missteps both of these shops suffered. We have successfully engineered, fabricated and fully tested a unique, lightweight, durable YG4 conversion for a fraction of the cost of the Colorado shop.
The Colorado Yamaha 120 HP, YG3 engine kit installed weight is 175 lbs and costs $3000. Installed weight here includes cooling system, electrical, oil tank, and exhaust w/o muffler. Price includes the box frame to mount the PSRU and the complicated engine mounts, with no supports to attach from the engine mounts to the airframe - in our case a gyroplane.
The GTX Yamaha 120/150 HP, YG4 engine kit installed weight is 175 lbs and costs $1900. Same ancillaries as above, and includes all supporting framework to the keel and mast of a gyrocopter.