Topic: Rotary Bikes

[CycleRanger]

Top 10 - or basically all of them.

http://www.visordown.com/features/motorcycle-top-10s/top-10-wankel-engined-bikes

I wasn't aware that Yamaha and Kawasaki had been rotary-curious.
Honda curiously missing from the list.

[Bankerdanny]

Maybe Honda just realized that there was no real point to a rotary bike.

[Terry in Australia]

I had a ride on a Suzuki rotary when my cuz took over the local dealership back in the late 1970's, it was a nice torquey thing and reminded me of a big single to ride, with one of the coolest instrument binnacles, but rotaries were too radical for most main stream bikers, so sales were few and far between.

I owned a 1972 Mazda RX2 Coupe in 1978-80, it was wickedly fast and crapped on V8 "Muscle Cars", but the fuel economy was woeful and it used lots of oil (worn rotor tips) and was pretty unreliable. Once it was going though (I became very adept at push starting it on my own) it'd do 140 MPH all day, I wish I still had it! Cheers, Terry.  

[CycleRanger]

Maybe Honda just realized that there was no real point to a rotary bike.

Or maybe they were just too busy selling bikes & cars to bother.

I wish I still had it! Cheers, Terry.

I'll bet you wish you still had both!

[Bankerdanny]

That too

[Bodi]

I rode a Hercules Wankel bike in the 70's for a day. A local racer and bike shop owner (Frank Mrazec) had one - it wasn't selling, so he let "friends" take it out for a test ride or a day to check it out (maybe to get it out of his sight?). With the speedo disconnected of course, so it would still be "new".
Interesting - smooth power, free revving, decent bike. Similar to a 250 twin 2-stroke for power and vibration but a lot heavier. And odd looking, the engine a strange shape. Top speed - didn't try, no speedo...
As far as I know he never found a buyer, the shop closed, and eventually he moved back to Czechoslovakia. Died a few years ago, maybe complications from another crash.
He was known as "Crazy Frank" or even "The Bouncing Czech" for his fearless racing style and frequent crashes. He even tried roadracing a CBX... that is certifiably crazy.

[CycleRanger]

https://lanesplitter.jalopnik.com/lets-have-a-close-look-at-the-hercules-w-2000-the-worl-1818704182

In the video the bike sounds like a chainsaw when revved a bit.

[MikeSimon]

  He even tried roadracing a CBX... that is certifiably crazy.

I know several guys who roadraced a CBX back in the day and some who still do. Not all THAT crazy. Once you get some of the chassis quirks sorted out. One racer even raised the engine in the frame to give it more ground clearance.

The rotary engine concept was one result of the perpetual search for a viable alternative to the oscillating piston design. It has its weak points, but Mazda managed to iron out some of the shortfalls and make it a viable production design. I remember Dan Gurney's Kudzu Race team, which campaigned 4-rotor Mazda engines in prototype chassis at the 24 Hrs of Daytona. The screaming sound of these things was awesome.

[Bodi]

Well, Frank's "normal" race bike was a TZ750 - and after spending a few months trying to tame the CBX he declared it too dangerous to ride in anger. I will take his word for it. He probably put the stock bits back on - including the zero miles speedo - and sold it as new.
There really isn't any excellent reason to try and make a CBX racer, it's just an exercise in nonconformity (and futility). The engine weights a ton, stock horsepower is not impressive - mods are possible but tuning is a bastard with 6 carbs (plus the inner cylinders are already tending to overheat in stock tune), the width of the cases severely limits lean angle, the chassis is overly flexible, and its weight distribution makes handling less than "race ready" even for its era. The sole attraction is the smooth power delivery - arguably a detriment in racing.

[MikeSimon]

"in its" era, there really was no class the CBX could compete in. Superbike was 750-1000cc.

[Terry in Australia]

There's a highly modified CBX that I see in the classic races here now and then, twisting itself into knots on tight circuits, but "Back in the day" all sorts of oddities were raced, even Kawasaki 6's were raced, albeit with little success.

The CBX was more about Honda demonstrating their engineering skills, than making a serious attempt at a 6 cylinder bike for the masses. BMW have been more successful with their K1600 variants, as they've managed to build a 6 that's only as wide as a 4.

[MikeSimon]

A liquid cooled motor can be narrower than an aircooled one, due to the fin surface required. If you dive into the history and the design details of the CBX, you will hear that the CBX inline-6 was only marginally wider than the CB750 Four due to the alternator not driven directly by the crank but a jackshaft - a design deature that Benelli had incorporated 5 years earlier with their 750 Sei in order to keep the motor narrow.
There are several CBXes being raced in Australia. Two of them by Roland Skate and one by Warwick Biggs

[Terry in Australia]

There are probably "several" CBX's being raced here in Oz mate, but with little success compared to the Big Kawasaki and Suzuki fours of the same era, pretty much just like it was back then. A nice bike, but an oddity, just the same.

[MikeSimon]

Mate, I didn't imply or want to argue with you that they are successful. I merely responded to your comment that you saw a "highly modified CBX" in classic races. Was probably Roland Skates' "Beastess"

[Terry in Australia]

Nope, that's not the one I saw. Who's Roley Skate?

[MikeSimon]

Roland Skate is quite known "down under" as a CBX racer and bike builder.
Maybe you saw Warwick Biggs' 82 Prolink. Both had a gentleman named Trevor Manley piloting their bikes when they had health issues