Hub Center Steering Kit from ISR of Sweden

ISR hub center steering kit

ISR NS2 hub center steering kit

Maybe you can't build a motorcycle quite like Stellan Egeland, but at least now you have access to some of the same exotic components he uses. The Harrier, Stellan's most recent custom, had a very unique look due to hub center steering, which more than looking good, worked very well, too. ISR, a Swedish company responsible for a number of components used by builders worldwide, is behind the steering on the Harrier and based on the excellent feedback from riders who rode the Harrier on both the street and track, is now offering the NS2 hub center steering kit.

Since the Harrier was BMW based, I'm assuming the steering kit will work on BMWs, though there are no specific details in their description. Whatever the case, this could be an opportunity for wider adoption of hub center steering on some custom street bikes, something quite a few fans of the technology will be happy to see. Now you don't have to buy a Bimota Tesi or a Vyrus to get the performance benefits, professional engineering and unique looks of this well tested hub center system.

It will be very interesting to see where this starts to show up. I like it.

Link: ISR
Related: Stellan Egeland's Harrier in action

ISR hub center steering on Stellan Egeland's Harrier

ISR hub center steering on Stellan Egeland's Harrier


  1. Nathan says

    The Harrier is cool…….

    but are there really performance benefits?

    I think you would get less feeling of what the bike is doing, but what would I know – my bike doesnt evening have dampening on the forks…

  2. Russel Caudell says

    I don’t like the steering linkage on this style front end. How about still using a telescopic tubes to steer the front end only and not for damping the front wheel

  3. Andy says


    Fantastic bike you built there. Very impressed with the design/effort. How does it ‘feel’ to corner?

  4. Matthew says

    I would like to see BMW take this seriously, come up with their own system, put it on a new R-Series sport bike, and sell it in the USA.

    I think every single one of those is wishful thinking on its own, let alone together.

  5. Paulinator says

    Push-pull cables are used on several experimental aircraft designs. They have the undesirable effect of diminishing some control feel. Maybe the added friction is a benefit on bikes?

    Lots of parts BUT I LIKE IT!!!

  6. todd says

    Russel, I think a telescopic steering tube would tend to bind and affect the suspension travel especially under braking. Bolleke has what I would think to be a preferred method of steering though it might flex more than the push-pull cables stretch. Nothing is perfect, not even conventional forks which twist, bind, and flex probably more than both these systems combined.

    Great efforts, I wish both ISR and Bolleke success.


  7. says

    Friction is not desirable as it tends to get “starting resistance” and you dont want that on a bike as it will get unstable going straith. The way we ran the cables with fairly long bends we could not feel more friction than what you get from normal steering bearings(or what they might be called in english). No one of the test riders did feel any problems with the feedback, and we had Öhlins best rider Anders Anderson helping us with the setup.

    Nathan, The benefits are: Same trail through the entire suspention stroke, no diving when braking( also meaning that you can have a softer dampening), extremely stable even with short trail, brakes and suspension are separated(does´nt bind when braking) and all of the parameters can be adjusted in anyway you want.

    Russel, you can use a system that i will try to describe in english but i might fail.
    Its kind of like two scissors side by side from the handlebar to the hub, but since the cables worked so good i cant really see any benefits.

    Anyway, im really happy that ISR has this product up for sale since they have put so much work into it. Everytime i get something from them it just makes me so happy, i´m an ISR junkie.

    I´m also very glad that there are so many of you who like the Harrier.

  8. powermatic says

    Although this bike might not be ‘beautiful’ in a 916-sort-of-way, I’d love to have one. Talk about a conversation starter. But as Stellen himself admits, the Elf/Honda GP experiment in the ’80s didn’t exactly have the major brands rushing to duplicate hub-center steering for either their race or consumer bikes, though I suppose other reasons may be at play, with cost, as always, being a priority. Still, I tend to look at MotoGP for the cutting edge that will be both practical and eventually trickle down to we, the consuming public, so for now I place this where it’s always been-a cool concept, but not worth the real-world trouble.

  9. pabsy says

    I love this sort of thing its great engineering congrats
    As an aftermarket part it would work at a butt clenching cost but not on a stock frame as the load paths on a stock frame are designed for a headstock, for customs tho it would be awesome
    When you work in cost, practicalities like turning radius, manufacturing tolerance, as well as maintaning an operating range after wear and tear, the humble front fork rules with no content but none of that matters this is about someone having an idea to improve certain performance areas getting in their shop and actually doing it and executing supremely well

    As a fan of fighters (i have a naked turbo gixxer..) the rest of the bike is just a jewel as well absolutely stunning congrats, i wish the factories would throw talent like this projects to stir the pot

  10. BoxerFanatic says

    Looks very interesting…

    But I have to say, I would much rather see the Duolever (Hossack) front end on a BMW R-bike.

    It separates the suspension action from the steering, as well as the braking actions, but has more direct steering input, with a linkage, instead of long push-pull cables that have inherent flex, and bowing under resistance.

    A new 4-cam Boxer engine (HP2S, new GS, etc..) with a Duolever front end instead of Telelever, Paralever EVO rear suspension, and looks drawn from the HP2S, the K12R-Sport, previous R1200S, and the BMW Concept 6 motorcycle… That sounds fantastic.

  11. WRXr says

    I can understand the advantage over normal telescopics, but perhaps they are aiming at the wrong make considering BMW already has the “alternative front end” thing covered.

    In fact, BMW already has two “alternative” front ends: Telelever and Duolever…both are neutral with not a lot of dive on braking….Is there an advantage over those systems?

  12. Paulinator says

    First, Thank you, Stellan, for addressing my question about cable friction.

    Second, the push-pull cables are used in some aircraft to simplify control routing. Simple is always good. This bike also uses redundant cables, so any safety and reliability issues seem to be covered, too.

    Last, does anyone know if Hossack had a positive relationship with BMW? Or did he get the NIH (not invented here) treatment? I’m not sure if pride or egos are factors in Big Motorcycle, but I could see BMW staffers feeling threatened by the shear talent that this one bike (and its creator) represents.

  13. Paul K says

    I agree with Pabsy, guys like this should have more factory support. As for this bike fantastic design (Vyrus with cables), beautiful engineering, HCS is the future……!

  14. Steve says

    I can see how this can offer handlingimprovements over traditional front ends. But in engineering everything is a compromise of some sort. When I see these type front ends I look at all the mechanical joints that all have to intact to function. Hopefully if one breaks or comes loose the front end doesnt fold up.

  15. says

    This sure is a subject that leads to discussion.
    I dont know why HCS isnt used in proffesional racing.
    With my limited driving skills, the advantage is huge even when you compare to Telelever and Duolever. Being used to race gokarts i tend to brake too far into the corner, disasterous with a fork but no big deal with HCS.
    If my next project will be a modern bike, i will not even consider anything else.

    I like what Steve wrote, engineering is always compromising, wery true!

  16. Swagger says

    BMW screwed Hossack to the wall and all but stole his work with “Their” alternative front end. Take a looks at his website for a little more details (even the inventor can’t poke a giant like BMW without fear of reprisal) it’s all there in text and subtext.

    I got to spend a 300 mile day flogging a Tesi, and I owned the unfortunately mismarketed GTS1000 and given the choice I’d not own a bike with conventional forks. Both (even the castrated and overweight GTS) tracked so well, it just didn’t matter what was being done. Point and shoot, period. How about a pothole in the apex of a decreasing radius corner, knee-puck almost down? Forks?…..expect to eat pavement.
    Swing arm front end? Well…you may get tossed but your chances of making the corner as FAR higher that with conventional forks.Why aren’t swing arm front ends commonplace? Change is scary. My take…..pure emotional response. You can even see it in the thoughtful comments here; discomfort makes otherwise accepting people look for fault in what they don’t know. Motorcycles have had forks up front in almost every instance, from the very beginning of the breed. This is now firmly ensconced in the motorcyclists sub-conscience creating an ingrained “truth” that’s hard to see past. Abuse someone long enough and it becomes ‘normal’, repeat a lie often enough and that lie becomes regarded at the truth.
    Ohlins doesn’t make this kind of suspension, they make forks. If you think that manufacturers aren’t swayed by $$$ then you’re deluding yourself.
    I think this is the future and should be embraced. I like forks on classic(or classic styled) bikes but I want a swinger up front on my modern bike.

  17. BoxerFanatic says

    It is truly sad how BMW seemingly brushed Hossack aside, and used his design anyway.

    But part of me is still glad that at least someone used it, instead of just sticking to the de facto fork paradigm.

    Telelever relieves some of the fork issues, but braking still does act on suspension, which Stellan doesn’t seem to like.

    The nice thing about Hossack’s design is that, depending on the geometry of the control arms, suspension compression as a reaction to braking, can be tuned in or out of the system. Riders are used to forward weight transfer on the brakes, and fully tuning it out of the front suspension is probably quite eerie to ride, where carting and other light race cars are used to a lack of front end dive on the brakes, either by stiff suspension, or lack of weight to transfer, or lack of suspension travel to compress.

    In a way, Hossack makes more sense than swing-arm, hub-centric system. The physics advantages are similar, but the packaging of the Hossack is better.

    The wheel hub and axle are simpler, and the rigid upright is located between the wheel hub and the steering interface, which is direct, not horizontally to the engine, with the steering input traveling all over the front end of the motorcycle on a series of flexible cables, or complicated, exposed linkages.

    Theoretically a Hossack type front end could be single sided, if it were built rigid enough… and the front wheel could bolt on like a car, or a Paralever rear wheel, making front tire changes a snap, as well as front brake service, although probably single disc, rather than dual, on a single sider… much like a single-sided rear suspension.

    Changing the wheel and tire, servicing the brakes, and maintaining the cabling and such on a hub-centric system would seem to be nowhere near that easy.

  18. says

    I was thinking of asking Bob Mighel about one of his 2wheel front ends for my ’96 R1100R when it devolves from go-to bike to next-project bike in a year or two…now I’m not so sure.

  19. froryde says

    Kudos to Stellan for creating the exception Harrier and to ISR for offering it as a kit. It’s small innovative guys like these that make things interesting for everyone.

  20. steve w says

    over the years i have personally built a number of hub centre steered bike, but on the foale principle whom i worked with for a number of years.
    this system (harrier) is an updated version of the difazio design which also worked well.
    yes these systems are at their infancy where tele forks have had years of design thrown at them but from a design and manufactured angle this is the future and would recommend any of these systems.
    i have in the past supplied front ends to be put on the conventional frames which worked well, but a designed chassis for this front end takes full advantage of this design,

  21. BoxerFanatic says


    I was thinking about a tilting motor works (Mighel) tilting front end on a BMW boxer, as well… I think that would be fantastic…

    But then I took a step further… why not a feet-forward race-car seating position between the BMW boxer engine and rear suspension and driveline, and the tilting front suspension? Basically a smaller, leaning-into-turns, round-profile tire equipped, more modern formula vee race car. 😀

  22. says

    While I appreciate all forms of backwards 3wheelers, I’m more a 3wheeler bike guy than a 3wheeler car guy. I like you line of thinking, though. Maybe with a K13 driveline. Would probably still be cheaper than a T-Rex.

    Volkswagen, where’s my GX3!?!

  23. Mike says

    I love it, ISR are now my favourite company for selling the HCS as a kit. So, does anybody know how much the NS2 kit costs and whe it will be available?

  24. says

    Mike, you will have to call ISR, the pricing will depend on what parts you need, you can get everything frrom the hub to a complete BMW kit with swingarm and frontcover for the engine like on the Harrier
    It is available right now.