![Mike Murphy�s beautiful �76 Rokon Cobra 340 motocrosser. Mike Murphy�s beautiful �76 Rokon Cobra 340 motocrosser.](/images/content/1-murphys-76-Cobra-Rokon-2-15-11.jpg)
Mike Murphy�s beautiful �76 Rokon Cobra 340 motocrosser.
![Murphy still races his �76 RT-2 in vintage events, riding it just as hard now as he did back then. Murphy still races his �76 RT-2 in vintage events, riding it just as hard now as he did back then.](/images/content/2-Murphy-Vintage-Enduro-2-15-11.jpg)
Murphy still races his �76 RT-2 in vintage events, riding it just as hard now as he did back then.
Rokon�s weird two-wheel drive Rokon Trailbreakers were one thing, but when Rokon decided to cash in on the expanding dirt bike market things got really strange! The radical machine they came up was a clean-sheet dirt bike design. Remember, this was an era of pipey, piston-port two-strokes with hand-grenade reliability. Motocross riders had to be clutch artists, constantly tap-dancing the shifter just to keep the engines in their narrow powerband. Hop off a modern bike and onto a vintage motocross bike and you�ll instantly develop respect for pro riders of that era!
Instead of fighting that battle Rokon used a simple, reliable 340cc Sachs snowmobile engine. Transmission? What could be easier to use than a snowmobile-style Salsbury clutch? Twist and go. With an infinitely variable transmission Rokon engineers didn�t have to worry about a peaky powerband and could instead tune the engine for maximum power and simply adjust the clutch to keep the engine revving at the power peak all the time. A great idea, in theory at least, but would it work on a dirt bike?
![Murphy�s 1976 RT-2 enduro bike uses a Cobra motocross-spec engine. Murphy�s 1976 RT-2 enduro bike uses a Cobra motocross-spec engine.](/images/content/3-Murphy-RT-2-Rokon-2-15-11.jpg)
Murphy�s 1976 RT-2 enduro bike uses a Cobra motocross-spec engine.
![Jim Hollander in the Italian Alps in 1974, on his way to a silver ISDT medal. Jim Hollander in the Italian Alps in 1974, on his way to a silver ISDT medal.](/images/content/4-Jim-Hollander-ISDT-1974-2-15-11.jpg)
Jim Hollander in the Italian Alps in 1974, on his way to a silver ISDT medal.
In the early �70s I was a little kid wandering around at gas stops at Enduros in Ontario and Western New York. Ever curious, I was drawn to the strange bikes with their pull starters and weird looking wheels. Watching Rokon riders pull-start their bikes was a constant source of amusement for me at five years old!
By �77 Rokon�s ride was over. The final Rokon prototypes, named RX500s, were a technological tour de force. The CVT remained, with a Maico 501 jug mated to the Sachs bottom end. The rear disc brake was mounted on the drive sprocket, which in turn was inline with the swingarm pivot. In many ways they were a cross between an ATK of the early �90s and a current BMW or Husky 450F.
![Dave Mungenast earned a bronze medal riding a Rokon for Team Canada in 1974. Dave Mungenast earned a bronze medal riding a Rokon for Team Canada in 1974.](/images/content/5-Dave-Mungenast-2-15-11.jpg)
Dave Mungenast earned a bronze medal riding a Rokon for Team Canada in 1974.
Rokon eventually recovered, and to this day continues producing 2WD Trailbreakers, but actual Rokon dirt bikes were history. Good ideas are good ideas, and through vintage racing they are reborn. Rokons, once considered somewhat crude in the execution of their radical ideas, have become among the most collectible vintage dirt bikes for good reason. They are rare, they are cool to look at and they inspire endless bouts of �what if?� bench racing in the pits. For all their faults the one thing Rokons always were was fast, and thanks to that awesome CVT tranny a Rokon rider is practically guaranteed a holeshot in vintage motocross!
Inspired to learn more about these innovative machines we tracked down Rokon ISDT star Jim Hollander (who later went on to start the Hot Grips heated grip company) and Rokon development rider �Rokon� Mike Murphy, who now runs a small business called Rokon Renew that specializes in building and selling vintage Rokon race bikes.
�I happened to live just within 100 miles of the Rokon factory in NH,� explains Hollander. �I was asked by the President of Rokon to try out the bike when I was at the ISDT in Dalton, MA. I fell in love with the simplicity and ease of riding it.�
![The last Rokon prototype still exists and is owned by Jim Hollander. The last Rokon prototype still exists and is owned by Jim Hollander.](/images/content/6-Rokon-77-RX500-Proto-2-15-11.jpg)
The last Rokon prototype still exists and is owned by Jim Hollander.
Rokon had proven themselves in 1973 with four finishers at the ISDT, but that publicity didn�t end the constant barrage of questions in the pits. �I noticed younger riders like myself, around 22 at the time, made a lot of jokes about it,� laughs Murphy. �They even called me �The lawnmower man!��
If you�ve ridden a snowmobile you know the biggest advantage of a CVT transmission is incredible traction, which Rokon capitalized on. Hollander describes its operation. �Rokon's transmission is a torque converter set up like on a snowmobile, with a front drive sliding double cone arrangement off the engine crankshaft and then a rear driven torque converter, which was connected to a gear reduction box before output to the countershaft sprocket. It is torque sensing in that as the rear wheel slips the pulleys tend to up-shift into a higher ratio. There was a learning curve of a few weekends at local enduros in New England, but then it was much easier to ride than a shifter bike.�
![When George Canellos brought his �74 Rokon to a VMX race at Gopher Dunes in 2009 his bike was the center of attention in the pits. When George Canellos brought his �74 Rokon to a VMX race at Gopher Dunes in 2009 his bike was the center of attention in the pits.](/images/content/7-george-canellos-Rokon-2-15-11.jpg)
When George Canellos brought his �74 Rokon to a VMX race at Gopher Dunes in 2009 his bike was the center of attention in the pits.
There were a few tricks to riding a Rokon effectively � things most magazine testers or weekend warriors never took the time to learn. �The hardest thing for me about learning to ride the bike was the disc brakes!� Murphy told us. �At that time we all had drum brakes that basically didn't work very well. The Rokon disc brakes did overheat but worked well at enduro speeds.�
![Motocross, enduro and dual-sport Rokon clutches could be tuned with different springs and ramps to suit track conditions. Motocross, enduro and dual-sport Rokon clutches could be tuned with different springs and ramps to suit track conditions.](/images/content/8-Rokon-CVT-Trans-2-15-11.jpg)
Motocross, enduro and dual-sport Rokon clutches could be tuned with different springs and ramps to suit track conditions.
Taking full advantage of the CVT required a few tricks as well. �I developed a technique of riding the throttle against the rear brake, a bit like the rally drivers did with rally cars, and it made the bike super fast!� Hollander says.
![Rokon continues building their unstoppable 2WDs to this day. Check out www.rokon.com for more info! Rokon continues building their unstoppable 2WDs to this day. Check out www.rokon.com for more info!](/images/content/9-Rokon-Trailbreaker-2-15-11.jpg)
Rokon continues building their unstoppable 2WDs to this day. Check out www.rokon.com for more info!
If you took the time to adapt your riding style to the Rokon they were effective race bikes. David Mungenast holds an honoored place in the AMA Hall of Fame. Among his many accomplishments is a bronze medal earned at the Italian ISDT in 1974 while riding a Rokon for the Canadian team. In 1976 Hollander won the overall at an US ISDT Qualifier overall in Cass City, Michigan over Dick Burleson and the Penton brothers. In Austria at the ISDT, Hollander was the top scoring American trophy team rider and sixth American overall. Murphy used the same Rokon for motocross and hare scrambles and modestly says, �I seemed to always stay up front with most of the fast guys.� Florida motocrosser �Rokon Don� Kudalski became famous for his speed in the sand about his auto-crosser.
Finding traction in sand and mud are one thing, but water could prove to be the CVTs undoing. �Rokon advantages?� Murphy says. �They always find traction and the disc brakes are great! Disadvantages? No engine braking and that rubber drive belt needs to say dry!� Hollander continues, �In deep water there was some slipping on the torque converter drive belt, but we finally got past that by slotting the belt edges on a table saw so they worked like a rain tire.�
Motocross and off-road racing were a lot different 35 years ago than today. We wondered if a CVT would have adapted as well to 'new school' enduro with all the extreme and motocross-type elements? Is it even necessary now that EFI four-strokes have such wide, smooth powerbands? �I would be curious to ride a Rokon with modern suspension,� says Hollander, adding, �I am also very curious about the Christini two-wheel drive system and wonder how the combination would be of an automatic with 2WD! A modern automatic transmission would benefit a modern race bike, but there seems to be a lot of resistance to automatics even after Husqvarna won the National Enduro Championship on their automatic in the �80s.�
![This is where it started. The first Rokons were 270-pound dual sport bikes. This is where it started. The first Rokons were 270-pound dual sport bikes.](/images/content/10-Rokon-1972-RT1-brochure-2-15-11.jpg)
This is where it started. The first Rokons were 270-pound dual sport bikes.
Interested in vintage Rokon enduro and motocross bikes? You can contact Mike Murphy at Rokon Renew by sending an email to RT340AUTO@AOL.COM
Thank you Jim Hollander and Mike Murphy for providing input and photos for this story! Stay tuned, because we�re on the gas to follow up last year�s successful Can-AM 175 build with a Rokon racer in time for Ormstown Vintage Off-Road Festival Aug. 28-29!