Roll-o-Flex
Roll-O-Flex article from SnowGoer Magazine
Our Families Roll-O-Flex Snowmbiles
The Do Not ride in Excess sticker!
1974 Roll-O-Flex Owners Manual
Vintage snowmobiles web site with Roll-o-flex spec sheets
Vintage snowmobiles web site with Roll-o-flex Brochures
Vintage
snowmobiles web site with 74 Rolloflex information & pics
Dayco Belts for Roll-o-flex
Timeline: 1973 Roll-O-Flex GT 340
In 1973, snowmobiling had been clearly defined as a sport and as a means of recreation. The first wave of failure in the industry had passed and the numerous remaining factories were optimistic about their futures. It was a time of technological experimentation and unique design. Some caught on, while others were forced into bankruptcy. Many of these remaining snowmobile factories were short lived after 1973, with heavy competition for market share.
One of these factories that was heading toward future failure was Roll-O-Flex. In September of 1970, they received a grant from the Canadian Government that enabled them to boost their production of snowmobiles to remain competitive in the market. The Regina, Saskatchewan-based facility featured several models for 1973; including the GT 340.
Roll-O-Flex snowmobiles all featured Yamaha engines in 1973. Under the hood of the GT 340 was a 338cc, 34 HP fan-cooled twin. When tested back in late 1973, this powerplant outperformed nine 440-class machines on the dyno.
This was, at the time, impressive horsepower for a 340-class machine. The claimed 34 HP was at 5500 RPM. The GT 340 had an aluminum tunnel which helped it scale in at about 320 pounds.
Roll-O-Flex engineers, through their dual exhaust pipe technology, were able to achieve higher horsepower from the Yamaha engine.
With the use of dual, straight, tuned pipes, the system sucked unburned fuel vapors into the exhaust system when the intake valves were open. The charge of the tuned exhaust system in turn forced the gases back into the combustion chamber, thereby increasing the compression. In 1973, tests of the GT 340 concluded that the technology of these pipes was a form of "supercharging".
This is just an early example of the tuned exhaust systems on machines today. Through the use of tuned exhaust ports and expansion chambers, horsepower is increased on modern machines much the same way as the Roll-O-Flex makers did with the Yamaha motor on the GT 340.
The Roll-O-Flex GT 340 also featured a disc brake, standard tachometer and speedometer, steel-reinforced rubber track and a 5 gallon fuel capacity.
The suspension was the venerable leaf spring suspension in the front. The rear suspension is what made this machine particularly unique. Called the Super Flexion, the system used a wheel-rail design, not far different from the Para-Rail design that was used on Scorpion snowmobiles. It was neither a bogie wheel assembly nor a slide rail, but some sort of combination of the two. It was similar to a slide rail system in that the two outside rails were coupled with the front and rear arms. Instead of hyfax or Teflon slides, however, the rails were mounted on a series of in-line bogie wheels.
The GT 340, with its unique rear suspension system, also had a unique handling characteristic. Starting at a speed of about 40 MPH, the rear of the machine would jump 4 or 5 inches sideways when following a straight, level course. This, of course, is a confidence-robbing feeling of the machine having more control than the operator. In a 1973 SnowGoer article written about the Roll-O-Flex GT 340, the subhead read, "There's a Yamaha 340 under the hood that beat nine 440's, but hold on at 60."
Adding to the feeling of instability, the GT 340 had a high center of gravity. This came from a combination of a high-mounted engine and a narrow ski stance. The overall height of the machine was 41.5 inches while the width of the machine was a slim 31 inches. Testing in 1973 produced an overturn rating of a paltry 36 degrees, when other machines of the day were reaching overturn angles exceeding 50 degrees.
It isn't fair to say, though, that the Roll-O-Flex line of snowmobiles was doomed from the beginning. In 1973, the company sold approximately 4,000 units of the 5,000 produced through a network of about 800 dealers through the United States and Canada. What appeal the GT 340 did have was the Yamaha powerplant and how the Roll-O-Flex engineers were able to get 440-class horsepower from the 338cc motor.
copyright SnowGoer magazine - February 1998
My Fathers - 1974 Roll-O-Flex Apache 440
Mine - 1974 Roll-O-Flex GT 340
- 1972 Roll-O-Flex GT 340 - 440 hood with 74 340 GT
Motor
Uncles' - 2 - 1974 Apache 340
Dayco Belts for Roll-o-flex Snowmobiles
Apache,Cherokee,Comanche 197 MAX1034M2 HP3001
Apache,GT 1972-74 MAX1082M2 HP3014
Cherokee 1972-73 MAX1082M2 HP3014
The Wild One 1974 MAX1034M2 HP3001
Commanche 1973 MAX1082M2 HP3014
The Wild One 1973 MAX1082M2 HP3014
This picture is a sticker on my fathers 1974
Roll-O-Flex Apache 440.
It says, "CAUTION - DO NOT OPERATE IN EXCESS OF - 120 MPH"
Another Picture of Dad's Roll-O-Flex Apache 440, remember 120 MPH MAX!!
Mark's Roll-o-flex 340 Apache
David's Vintage snowmobile brochures - rolloflex included (from 1969 - 1974)
Roll-o-Flex Parts & Information Wanted!
I would like to hear if you have any parts for rolloflexes or are in need of something. I will post the items here.
WANTED - Looking for a rolloflex GTX wildone. The model i'm looking for was built in 73 / 74. It had a white hood. Contact Loius at ljsign@sasktel.net - posted Mar 2008
Rolloflex for sale - the one listed above as Marks - contact Corey below for contact information.
eMail me corey@cabler.com
