Rotary Engines in motorcycles, I believe it never grew big because of the gyroscopic effects and what they would do to handling.


Anyway- Bashing british bikes eh?  I won't come on too defensive- just a little bit.  Norton was inteed trying to make a comback simaliar to Triumph Motorcycles Limited, however the public interest simply wasn't as strong as it needed to be.  Norton was relying on heavy deposits from potential consumers to develop themeselves to the point of becoming a mass producing manufacturer.  Turns out they weren't able to gather enough of a customer base, and ended up calling off production.  They returned all of the deposits.  Its a shame- the previously posted Norton prototype is about as sweet of a bike as anyone makes...

As a side note to the British Bike Bash... I have 20k on my 95 Triumph Speed Triple.  The chain, tires, and oil/filters have been changed and thats it.  No reliability problems at all.  Not bad for the 900cc triple cylinder's first year of appearing in the US...

Suzuki RE5?  I crashed one of those

My dad bought one almost two years ago to restore.  Last spring, after most of it was put together, we were working on the brakes, then I took it out for a test ride.  The damn thing didn't want to go above 50.  And it was slowing down on its own... a lot.   I stupidly kept riding it home as the front brakes got hotter and tighter.  All was good until I was pulling into the driveway very slow and hit a patch of sand.  The front locked up and slid straight as I was mid turn.  Down she went.  A few hundred dollars (new gauge housing and a few other parts) and a few weeks later it was done. 

That thing was a heavy beast.  Very long bike too.  I kinda liked the engine noise, it was something unique, but for everyday I think I prefer the sound of cylinders.  Smooth power, but no rocket ship, due to all the weight.

It would be interesting to see what modern engineering could do with a new rotary powered bike

I would love to see more of these turbine bikes.
http://www.bikez.com/motorcycles/marine_turbine_technologies_y2k_turbine_superbike_2003.php

Power: 320.00 HP (233.6 kW)) @ 52000 RPM
Torque: 576.30 Nm (58.8 kgf-m or 425.1 ft.lbs) @ 2000 RPM

Also rotary engines drink oil like a biatch. I know someone whos got one of the new mazda rx7's with the rotary engine, says he has to top the oil up every month or so because its burnt it all. Hes selling it and getting something admittedly less cool but more economical.

One of the issues with rotary engines (in autos atleast, not too certain about how well this translates to bikes), is that autos rely on the engine block to increase rigidity of the frame. Rotary engines are not built to supliment rigidity whatsoever.


That, and I think a modern powerful rotary would generate an akward gyroscopic effect that could have a very adverse impact on handilng.


But, standard engines found in motorbikes are already powerful, low displacement engines, that simply need to rev to make their power in most cases. Which really doesn't create a need for rotary engines at all in a bike (as a rotary behaves much the same way).


The simple answer is its just not practical.

Quote from: TadMC on June 05, 2006, 10:25:11 PM
I wonder how that'd sound too just idling

That same site http://www.suzukicycles.org/RE5/RE5-Rotary.shtml has some WAVs of the engine idling.

Quote from: ets_gs500f2004 on June 06, 2006, 05:18:02 AM
BUT the big problem is that they do prematurely use... that means it cant last as long as the other engines due to the oiling the piston and cylender is alot harder...

That's not true.  I've had plenty of seven's with over 200,000 miles that ran perfectly well...even a 10th Anniversary Turbo II with 254,000 miles (and it required a 28lb boost spike to kill it).

Quote from: tealetm on June 06, 2006, 06:56:49 AM
Rotary Engines in motorcycles, I believe it never grew big because of the gyroscopic effects and what they would do to handling.

Gyroscopic effect would only be a relevent concern if the engine were mounted laterally.  The RE5's engine was mounted transverse....ally...whatever...the eccentric shaft went across the bike instead of with it.  The gyroscopic effects with this engine were similar to my 250 ninja.

Quote from: Kasumi on June 06, 2006, 02:03:23 PM
Also rotary engines drink oil like a biatch. I know someone whos got one of the new mazda rx7's with the rotary engine, says he has to top the oil up every month or so because its burnt it all. Hes selling it and getting something admittedly less cool but more economical.

Rotory engines do use oil to lubricate the housings, but if you're using over 1qt a month in an RX-7 with an unmodified e-shaft then there's likely leaky seals aplay.  On average, a 13B's oil metering pump dumps 1qt every 5000 miles.  If you don't like it, then remove the oil metering pump and run a 100/1 2-stroke mix.

Quote from: Esih on June 06, 2006, 02:28:06 PM
One of the issues with rotary engines (in autos atleast, not too certain about how well this translates to bikes), is that autos rely on the engine block to increase rigidity of the frame. Rotary engines are not built to supliment rigidity whatsoever.

Neither my F150, RX-7's, Supras, Porsches or BMW's used the engine as a stressed structural support.  My Uncle's ZR1, C5 and 05 Z06 are the same...engine is not a stressed member.  My mom's Ford Crown Vic is the same.  My step brother's mom's '03 Mustang GT is the same.  None of these cars use the engine as a stressed member.  In fact, the only cars I can think of that use the engine as a stressed member are front wheel drive cars.

On the other hand, the RE5 used the the engine as a stressed member and it did just fine.  It's a design feature.  They're not going to put a stock 13B in a bike, so adding an extra ear-mount here and there won't be a problem.

Quote from: makenzie71 on June 06, 2006, 05:52:54 PM
transverse....ally...

I think the word you're looking for is longitudinally 

But yeah, he's right... Rotary's are pretty long lasting, and since they don't waste power by reciprocating, or only produce power on one of four strokes... they're that much more efficient. Oh and because they don't reciprocate, there's less friction... much easier to make something rotate then to make it go back and forth!

no...longitudinally would be "with" the frame, not across it.  I'm looking for "transversely".

longitudinal = from front to back
lateral = accross

Quote from: joedude on June 06, 2006, 06:53:45 PM
longitudinal = from front to back
lateral = accross

Exactly 

The E-shaft on the RE5 is across the frame...the automotive world says this motor is mounted "transeversly".

QuoteGyroscopic effect would only be a relevent concern if the engine were mounted laterally.  The RE5's engine was mounted transverse

That's why I said something... Lateral and transverse is the same thing.

ok...but in that first post you said I was looking for "longitudinal" and I wasn't.  Longitudinal means "parallel to".