Rotax Rotary Valve Single Cylinder!!!

[Southern Hill Custom]

I dag letade jag lite "kunskap" till ett nytt skoterprojekt..

Det jag letade fanns inte, men jag hittade detta!!!!

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Serial No. 103, Rotary Valve Single Cylinder,
334.5cc, Bore 78mm, Stroke 70mm, 39 hp @ 7000 rpm
This is certainly one of the most interesting and rare engines in the collection. It is a prototype single cylinder rotary valve engine that Rotax created in 1969. It could have become the 1971 340 Blizzard engine but Polaris’ new clutch sent Bombardier and Rotax back to the drawing boards for future racing engine/clutch designs.
With the clutches used prior to development of Polaris’ design, low-end power was a must, and the broader the power band was, the better the design could perform. The rotary valve design allows a much longer intake duration while still being able to close the intake port before losing any fresh charge back out the intake port. It also frees the rear of the cylinder for additional transfer ports. The design effectively widens the power band while being able to make more peak power.
This particular engine has no magneto or external flywheel. It is equipped with breaker points, which ride on a cam ground directly onto the crankshaft. The points mount on a rotating plate which can be positioned by pushing or pulling on the rod that comes out of the “magneto housing” beneath the coil. The engine could be retarded manually for starting. The system used a battery to power the coil and was termed a constant loss ignition system.
Helmut Roteh, who was in charge of Rotax R&D, brought this engine with him on a visit to Halvorson Equipment Company. Through a translator, Roteh explained the engine’s design and features and left the engine for the Halvorson R&D department to test. The RV engine made its way up to Doug’s Inc. in Virginia, Minnesota, for Doug Denhert to make a pipe for it. The engine was not legal for use in anything but the open class where it was just too small to compete. Doug did race the engine once (illegally) just to see how it would compete. It was impressive but Doug backed off so he wouldn’t make the final and a possible inspection.

Är det någon som vet mera om denna motor?

Blev helt plötslig intresserad av att göra en replika av motorn...

//Lars

[Fox Trac]

Vilken Frän

[tapio]

Väldigt lik en gocart motor..

[Holländaren]

Det är bara börja bygga! Har själv haft funderingar på ett sånt projekt.. Men det var ju det där med tid