And 1.5 l F1 piston engines used to make 1200 hp. Not sure what that has to do with a rotary engine bike.

The difference between a F1 engine and a rotary is that I can personally build the 300hp rotary (I have done several), whereas you cannot afford to build an F1 engine.

With porting, I'm positive that I could up the hp output on a RE5. What's it's stock output?

The RE5 is an interesting historic footnote, but it isn't a very good motorcycle. There are still Norton rotaries around, buy one of them - they make decent power stock. But a modern 600 will still walk all over them.

my understanding with the suzuki rotory bike had the same problems the older mazdas did, the Apex seals kept going too easy. i seem to remember an old shared joke about the Mazda drivers, when they past eachother on the road, they held up fingers on a hand indicating how many engine changes under warrenty.  I also understand the bike was a mutha to start. buzzy,didnt make any power till high in the rpms.

dont know, old dusty memeries. some may be right, perhaps not

i have been thinking about the benefits of a rotory powered motorcycle for a while now just off on my own, and i just stumbled across this thread.  i can't figure out why someone hasn't tried again yet with a newer design.  i mean, hell the 1.3L out of the old rx-7 made 200 some hp?  they weigh less, they are smaller in size, they are infinetly smoother, and they have a powerband similar to what most motorcyclist already expect, relatively low torque, and hp high up in the rev range.  

emissions are more relaxed for motorcycles than cars, so i don't think that would be a real problem.  also, rotories are excellent for turbo'ing since they typically run pretty hot.  (if you read up about the re5 you'll see heat is one of the reasons it didn't sell so well, and the reason for the huge radiator).  only real drawbacks i can see is the mileage (who cares, most of us ride for fun anyway) and the heat.  

i'm not saying that it's the perfect solution for everyone, but i would definately consider purchasing a rotory powere bike if one were available in some sort of modern trim.  clearly it has some advantages to a piston engine, especially on a bike.

Well, if you want a rotary bike custom built, I could build it for you. Of course, you could buy a lot of GS500's for the same amount.

Ok Here is another real problem with the Rotaries like that RE-5...It is ugly...I mean just plain eyesore.
Anyway to fix that problem...and still have it naked...Yea I know put a block of fins on it.
Cool.
Srinath.

Somebody gotta help me out here.  The only Mazda rotaries I've heard of (not including the newest iteration) were the 12A & the 13B, both of which date back to at least the early '70's.  Both were two rotor engines.  The only 3 rotor engines I've heard of were for the Mazda factory sports racers from about the mid to late '70's I think.  What's the deal with this "20B 3 rotor" ?

Quote from: bobSomebody gotta help me out here.  The only Mazda rotaries I've heard of (not including the newest iteration) were the 12A & the 13B, both of which date back to at least the early '70's.  Both were two rotor engines.  The only 3 rotor engines I've heard of were for the Mazda factory sports racers from about the mid to late '70's I think.  What's the deal with this "20B 3 rotor" ?

the 3-rotors probably are race-only.  there are some problems involved with assembling them...

FWIW, my 85' RX7 GSLSE with the FI 13b had 155k miles on the stock engine and drivetrain when I sold it to another Rx7 lover who continues to drive it. It would still run mid 15's with no engine work at all and on the stock clutch and h rated tires.
Evan  

i think the biggest complaint of the early rotories was the Apex seals gave out with relative frequency. and the Dished Rotors wernt as efficient in changing the power of Combustion into motion as the newer design is.  but i dont have a whole Lot of knowlege on this. i could be completely wrong, but remember APEX seal being topic most of all