Roller Skis

A Small Wheel World

Rottefella Appeals the Prolink Verdict but CEO Quits

Rottefella decided in September to continue its legal fight against Amer Sports over the Prolink binding system. Rottefella believes the first court decision by Oslo District Court is wrong and the company is especially discontent with the court’s nullification of the two patents. However, Rottefella’s CEO Christer Johnsen did recently, on 18th of October, leave his position but the reason for that has not been publicly revealed.


Cross-Country Screwdriver

The screwdriver par preference in relation to cross-country skis and roller skis is the Pozidriv screwdriver, and especially one with a tip of size 3 of that type, abbreviated  PZ3. That is so because of an international standard called ISO 7794 which specifies that screws of the corresponding screw drive and size shall be used for cross-country ski bindings. It is important not to confuse the Pozidriv with another cruciform screw drive, namely the perhaps more common and similar looking Phillips screw drive, so one uses the right tool when mounting, unmounting or adjusting bindings. The Pozidriv screwdriver has not only wings of a slightly different design than the Phillips screwdriver but more easily recognized a sharp edged rib between each and every wing which the Phillips screwdriver does not have.


Pozidriv 3 (PZ3) screwdriver tip. Notice the sharp ribs between the wings.

Jan Ottosson’s Roller Ski History


Jan Ottosson at Åsarna Ski Stadium on his first pair of roller skis, the so-called “Grimmer rollers”. The ski boots, Thomas Suveren, are from around the same time as the roller skis, circa 1973. Photo: Henrik Ottosson

This is an interview with Jan Ottosson done 8th of June – 25th of August 2016. Swedish cross-country skier Jan Ottosson, born in 1960, is two times Olympic champion, several times Swedish national champion and four times winner of Vasaloppet. He is now a cross-country ski trainer at Fjällgymnasiet, a ski high school in Sweden. The interview was done in Swedish and translated into English by Magnus Johansson.

MJ: When did you start roller skiing, and for what reason? Had you been recommended to start roller skiing for ski training during the snowless season or was it your own initiative?

JO: I started roller skiing at my own initiative. I read about roller skis as a training device and became curious. I find [documented] that I roller skied when I was 14 years old; maybe I started the year before when I was 13. It was with the East German model of roller skis. Me and my 5 year older brother bought a pair each and started roller skiing.

MJ: Was it the so-called ”Grimmer rollers” (after the East German top cross-country skier Gerhard Grimmer) you and your brother acquired? What did you think of them? Did they give you the training you had hoped for? A common notion is that they did not give a very ski-like training.

JO: It was ”Grimmer rollers”. I was so young then so I do not know what they really were like, but anyway, I trained on them.


Some of Ottosson’s roller skis through the times. From front to back: “Grimmer rollers” (with ski boots), JEH, JOFA (wood shaft), JOFA (metal shaft), Edsbyn, and for modern reference Swenor Fibreglass. Photo: Jan Ottosson

MJ: Can you tell me more about those roller skis?

JO: It is so long ago, but I trained on them a couple of summers.

MJ: Who was the manufacturer?

JO: Don’t know.

MJ: What did they cost?

JO: Can’t remember.

MJ: What are the specifications? The difference in weight and size were big between front wheels and rear wheels to obtain a fair balance of the ski. Antenna wheels are used even today by Marwe. Did the ”Grimmer rollers” come mounted with NN-75 bindings?

JO: That is correct; they came with bindings mounted.

The roller skis in rear view. The Edsbyn roller skis had the wheels worn out and discarded so we had to estimate their wheel size.

The roller skis in rear view. The Edsbyn roller skis had the wheels worn out and discarded so we had to estimate their wheel size. Photo: Jan Ottosson

Jan measured his roller skis and the results are given below:

Grimmer Rollers”

Aluminum frame; aluminum, plastic and solid rubber wheels.

Wheelbase: 430 mm

Distance to antenna wheel: 485 mm

Front wheels gauge: 80 mm

Rear wheels gauge: 72.5 mm

Frame width: 125 mm

Frame thickness: 20 mm

Ground clearance: 26 mm

Front wheels: 115 x 15 mm

Rear wheels: 55 x 18 mm

Antenna wheel: 40 x 10 mm

Weight: 3200 g/pair

MJ: What type of roller skis were your next pair?

JO: I believe the next pair were Road-Ski but I am not certain. I also had Oddmund Jensen, Edsbyn and JOFA; all of these had three wheels.


Aluminum shaft; aluminum and solid rubber wheels.

Wheelbase: 810 mm

Shaft: 40 x 25 mm

Wheels: 120 x 15 mm

Gauge: 100 mm

Ground clearance: 50 mm

Weight: 2600 g/pair

JOFA (wood)

Wooden shaft, laminated; aluminum forks; solid rubber tires on aluminum rims.

Wheelbase: 840 mm

Shaft: 45 x 20 mm (narrower at the front)

Wheels: 90 x 22 mm

Gauge: 90 mm

Ground clearance: 42 mm

Weight: 3400 g/pair

JOFA (metal)

Aluminum shaft; solid rubber tires on aluminum rims.

Wheelbase: 840 mm

Shaft: 40 x 25 mm

Wheels: 110 x 20 mm

Gauge: 85 mm

Ground clearance: 42 mm

Weight: 2800 g/pair

MJ: After the three-wheel era of e.g. JEH and JOFA in the 1970’s and very early 1980’s, which ones were your first pair with barrel-wheels?

JO: I believe I had a pair of Svenskskidan. If I am not totally wrong, they were the first roller skis with that type of wheels.

MJ: So barrel-wheels on roller skis is a Swedish invention or original construction?

JO: Hans Person from Småland, Sweden, got a pair of test roller skis from Sivert Höök, (I am a little uncertain of his name) also from Småland, and Hans then started Svenskskidan. I worked in the summer of 1983 in Vålådalen in Jämtland and got to test these new roller skis on gravel roads. They had wide wheels that coped well with the uneven surface of those roads. Svenskskidan later became what is known today as Elpex.


Aluminum shaft, solid rubber wheels.

Wheelbase: 840 mm

Shaft: 40 x 25 mm

Wheels: 80(?) x 60(?) mm

Ground clearance: 28(?) mm

Weight: 3800(?) g/pair

MJ: Regarding development of other equipment, was there some detail that you remember particularly improved roller skiing?

JO: The pole tips became better over time.

MJ: How appreciated was roller skiing among elite skiers during your junior and early senior years? Did it go without saying to train a lot of roller skiing in the bare ground season? How much did you train? Or were there many with the same attitude to roller skiing as Sixten Jernberg who thought it might be good for poling training but that he rather ran instead?

JO: We trained on roller skis about 30-40 % of the training time (1976-1980). Running dominated the training. Later, when skate skiing came, the time on roller skis increased. When I started with the Grimmer rollers I didn’t roller ski that much but trained running and pole running and other things. It is likely not possible to compare the roller skis of Sixten’s time to what we have now, and it is not only the roller skis that have developed, it is all equipment and, for example, the access to roller ski courses.

MJ: That you trained more on roller skis when skate skiing came, was that because the new technique had less in common with running and pole running?

JO: Skate skiing was a new way of skiing and a new activity to train and therefore it automatically meant more roller skiing. We started with the one-legged skate on classic roller skis and then when skate roller skis came we could use real skate skiing technique.

The Prolink Court Case

Yesterday was the expiring date for Rottefella AS to pay Amer Sports’ costs for the court case against Amer Sports regarding the Prolink binding system. That is what happens when you sue someone and lose in court. Amer Sports with its companies Salomon and Atomic were found not guilty on all five charges brought by Rottefella.

None of the charges were about the binding technology itself, because that technology is now in the public domain and free for anyone to use. What Rottefella charged Amer Sports with were instead the alleged violation of two Norwegian patents regarding a ski boot sole construction, one protected ski boot sole design, a marketing law and the illegal use of the protected trademark NNN. The patents were found invalid by the court and regarding the other charges the court could not see any violations.

The verdict was almost like a disaster for Rottefella. Not only does it have to pay circa 2 million NOK to Amer Sports and probably at least 1 million NOK to its own laywers, but it got two patents declared invalid and attracted considerable badwill for the whole action. Why didn’t Rottefella instead welcome Amer Sports, Salomon and Atomic to NNN and use the step of its competitors to further expand the use of NNN and NIS?

Prolink Is Legal

Yesterday I was informed by Amer Sports, the owner of Salomon and Atomic, that the Prolink cross-country binding system was found legal in the trial held in Norway where Rottefella had sued Amer Sports for having broken the law with Salomon’s new binding system that is compatible with Rottefella’s binding system NNN. I will get back with further information if I get to read the court decision.

Rottefella Adjusts — but Only Some Things

Norwegian World Cup dominant binding producer Rottefella has adjusted the mounting template for its screw mounted bindings by moving the pin line 2 mm forward. This is for compensating the slight tail-heavyness that results from the circumstance that the binding adds more weight behind pin line  (and balance point) than in front of it. However, Rottefella chooses not to adjust the mounting recommendations for Excelerator NIS plates despite the fact that those move the balance point further backwards than the screw mounted bindings do.

I am developing a universal mounting template that will take these balance point shifts into consideration. More about that later.

Salomon Prolink

Not surprisingly, the new binding Salomon Prolink has already become a favorite with some retailers. Oslo Sportslager in the Norwegian capital has decided to recommend for roller skis Salomon bindings only this season. This is because they want to go for a thoroughly screw attached binding after the reported problems with NIS bindings accidentally sliding off the mounting plates. Rottefella recommends and provides a special safety kit with a drill, mounting templates and screws for attaching a safety screw under the flexor of the binding that goes through both the NIS plate and the top surface of the roller ski shaft. Oslo Sportslager found it easier and better to use the directly mounted Salomon Prolink binding with its 5 screws per roller ski instead of the now 9 screws for NIS bindings and their separate mounting plates.–vi-er-eksperter-pa-rulleski-1440.aspx