Public Group
Active 1 week ago
Group Leadership
- Group Administrators
-
-
This group is open to all registered members of the site.
New Dynavector Moulton?
- This topic has 17 replies, 7 voices, and was last updated 10 years, 10 months ago by
.
-
Posts
-
Does anybody have some information about the bike that apparently was presented recently in Japan?
https://www.facebook.com/moulton.ocj/photos/pcb.402738909926318/402738869926322/?type=1
Looks like a simplified construction. The front suspension is by external coil springs in tension. Probably much cheaper to make (and non-separable), but looks atrocious, I can’t imagine AM coming out with something so inelegant.
Speedsix from the German Moulton forum says that the “cross supports” are made from Kevlar and designed to stabilize the frame against torsion forces. He suggests to call it the “biplane”.
After all, Dynavector also makes model airplanes 🙂
Dynavector is a Japanese importer of Moulton bikes for many years but it seems they have become involved with development. So far, I have known Dynavector only as a manufacturer of high end turntable pickup systems.
Keith, I thought that the external coil springs were added to the spring in the handlebar post, for an even smoother ride. But you are right. This foto shows that there is no such connection:
Not necessarily a Dynavector development. The Japan Moulton Owners Club hold their summit meeting and gathering at the beginning of June, usually attended by Moulton, and new announcments made there.
I presumed the ‘spars’ were under tension but on closer inspection think they might work under compression?
Looks somewhat inelegant whatever.
Hi! I think inelegant is being rather kind. The whole thing looks quite ‘Heath Robinson’ compared to to the usual spaceframe set-up. Also it looks like mounting and dismounting will be less convenient, unless you use the ‘forbidden’ leg-over method that is!
Sometimes simplification means less weight. Maybe that is what’s behind the outer coil springs. The tubes must be pretty thin if they need additional stabilisation by the red rods. I would like to know something about the material and the ideas behind it.
I don’t like the colour setup but apart from that – I wouldn’t refuse if someone offered me a test ride.
I think their is more to those front forks than we realise. They require serious analytical thinking as to their operation.
I think the arrangement includes a pivoting bellcrank between the styrrup crown and the tyre, the bellcrank motion connects the coil springs to the leading link of the wheelaxle. My thought is they have designed a clever arrangement to make a variable spring rate , when the link is horizontal, the ride will be soft for small axle movements, as the axle link deviates from the horizontal ( large movements ) the spring rate will become progressively stiffer ” Rising rate suspension” . The effect is to make the ride soft and supple for smaller movements , yet stiffen in a progressive manner to accommodate larger movements. A soft ride without bottoming out of the suspension.The Dynavector frame, take a look at the butting of the tubes, is the frame metal of carbon-fibre? If carbon fibre, then perhaps those external string tubes are protective fenders, carbon fibre being damaged in a spill, lacking the “dentability” of steel.
Technically the springs may be highly sophisticated and offer a variable spring rate but they look like what I use to weigh any fish I catch.
AlexThe Dynavector may be a proving model, to test the new ideas and components, for production the parts may receive attention to styling concerns
I suppose they might be able to have shorter, thinner springs and hide them in a tube but that would result in 3 “tubes” at each side of the front end which I suspect would look over-complicated and messy.
Of course they might come up with a more radical and better solution in due course assuming it is a “proving” model which “adds value” to the riding experience.
- You must be logged in to reply to this topic.