Another thing about the RAVE is that it is also only on 2 strokes.

The rotary valves you were talking about are also only for 2 strokes and they where probably the best 2 stroke engines ever. Insted of having reeds it used a disk that had cuts in it (looked like a half pie). Depending on how they are cut can effect the emount of charge that goes in the cylinder. This method pumped out equal and reliable charges and upped preformance greatly.

Unfortunaly reed technology has somewhat caught up and now skidoo is using case reeds. The rotary design is gone but possible ready for a comeback. One such rotary engine was a 583 and 670 motor in a skidoo.

I belive that shops dont work on rotax motors becasue they are just not upto date on how they are built. THey are a very high quality motor that needs special training due to how parts go and work together. There is no finer small engine then a rotax.

 

Oh hell, as long as we're correcting each other... The reason for raising the port isn't to allow more flow, although it does do that, it raises the top of the exhaust port which changes the port timing which allows higher rpms. This is what engine tuners do to 2 strokes to make HP. Its kinda like changing the cams on a 4 stroke. The obvious side effect being reduced low end power so, as mentioned, RAVE, KIPS,Etc is a way of providing the best of both worlds.

 

Hey mar, when you say rotary, do you mean like no pistons, just a spinning rotor... If so, I hope that Doo does bring it back from the dead. (I dont know if doo ever used that design, but I know a company used it in a motorcycle a long time ago.)

Plus if they used the rotary motor, the motor would have hella power (No up and down motion just a spinning rotor)

If that is not what you were talkin about oh well[img]i/expressions/face-icon-small-blush.gif[/img]

 

they don't break much, so they don't make any money on them. the dealer here say they haven't seen any of the ones they have sold. most performance places say they already have a good engine, so it isn't easy to get more hp, without somework on there part. but if you need someone call gary at tvi, he has all kinds of stuff.

 

sounds like teh RAVE is just a fancy word for a power valve.. which CT racing makes

 

But its not powered, it just moves when a certain amount of exhaust flows (or something like that)
And RAVE has been with doo for a long time.

 

powervalves dont rely on Power to work.. but rather exhaust gas pressure which pulls teh slide up and opens the port. the powervalve that CT currently uses is actually a bombardier mechanism( watercraft i believe) and mated to a specially cast Pro-X cylinder

 

OK, I was not sure what you meant by power, I thought you meant like electrically triggered or something.

 

<< It all about the dollar. They dont have any information on it and they dont want to spend the time or money to get the info. They probably have most of the Jap manuals cuz there are so many of them out there but when it comes to an engine they will see very few of, they dont see the need to invest. They may also be concerned with parts availability.
Being a service manager for many years I can understand their decision but it sure doesn't help the shops image. >>



Hit the nail on the head!

 

...Speaking of powervalves, I believe the Suzuki LT250Rs had them from the factory as well. I don't know about the 500s, they probably did as well.