The goal is to build a kind of snow-bicycle or snow-tricycle. There are two or three on the web, there's a video here:

http://www.recumbentblog.com/2009/08...#comment-26936

The Question: Is that just a small snowmobile track? Some standard track from some other source? Is there some easy why to obtain/build such a thing?

What about those rubber tracked snowthrower tracks. They're small and flexible.

Ray

In the video they don't show a close up of the track, but to me it looks like a tractor or truck tire with the side walls cut off.
Vince

Hard to tell, but it looks to be cogged on the inside, so I'm guessing a snowthrower track.

I guess the first Q is why? Seatle doesn't git enough snow to have the streets covered hardly at all does it?

The only logical app for this would be a town that has snow covered streets all winter - and then put skis up front. But if those two wheels up front are OK - I see no call at all for the track in the back? Unless it is for exersize only and the additional drag of the track is looked at as a good thing?

They have track kits like this for dirt bikes (ski in front). Search "snowbike" I think?

Camoplast is likely the OEM on the tracks.

For something cheap - you may go to the local snowmachine graveyard in your area (I am sure that you won't hafta look too long in your area) and fetch an old track off a "short track" trail sled. This will be 121" long x 15" wide and have two drive slots in it. If that burr is still up your ___ you could slit the track to prox width as this one with one drive slot in the middle of it. While your at the graveyard you will want to git a "driver" (involute) for it as well. Maybe even the axle that it is on and then you can cut it down yourself. These are generally 1 to 1-1/4" hex and prolly 4140 type materials...

A track off a SnowHawk may werk as well - but I doubt that there are good used ones available yet. ???



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Think Snow Eh!
Ox

The honda snowblowers use those. But given the cost for replacement parts
for them, you'd be better off finding some other source!!

Jim

"Why?" - Because, well, for the 2 weeks every 3 years the place is under snow, riding around a human powered snow mobile would be efficient and have enourmous hack value. Likely make the news! And it would be fun to build...

Of course, the "why not put good snow/stud type tires on a bike or trike" answer makes a lot of sense too.

But thanks for the replies...

Just don't underestimate the power it takes to move thru the snow. Packed and frozen may not be too bad, but fresh heavy wet snow- you may turn a lung inside out while someone passes you on foot!!

Long live the two stroke!!

True enough. Chains and studs work well enough on shallow snow, slushy roads and ice (my daugher commutes most of the year through Burlington, VT on Hakka studded bike tires), but you won't get far in deep snow unless you can stay on top of it. I suspect that there are few ways you will pedal in deep snow without a very intense workout. The belt may work better than a tire on the back in the machine shown in that video, but I think that if the snow is not well packed the front wheels will be hard to roll and even harder to steer.

I'm lookin' forward to a blog about this here daughter.


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Think Snow Eh!
Ox

The standard motorbike conversions I've seen, use
skis on the front and tracks on the back.

Jim

Sure looks to me that the machine in the video would make a hard nose dive into any snow deep and soft enough to optimize that track.....
...and forget being able to peddle it.

Fun though and every bit as practical as a Sterling heat-engine powered cooling fan.....

Bob
Edit: maybe for this demo, he replaced the skis with his optional wheels, it is dry after all..... now, about that prime mover....

The undercarriage and track are comming from this machine.

http://www.snow-hawk.com/model_home_hawk_jr_60.aspx

It's a 90"long x 6"wide Camoplast track.

Should be avalaible at any retailer

Martin

Me too....

Heck Ox, I studded up a set of plain ole 2.25 x 26" mountain bike tires
using 6-32 pan heads (50 or so on each tire), and ride it around the
plant during luch time....Yup I'm the nut out there with the snowplows.

Me thinks the belt needs to be about as thin as you can get, read
under 1/8" thick, as the bending and straightening load (as it
goes 'round and 'round) will use up a goodly portion of the
"available horespower" .

Lungs turned inside out or not.....

How about adding a second rear wheel behind the first (the driven one)
on a spring loaded swing arm, like a motorcycle, and using a
small tractor tire (cut as described) looped around both.

The rear brake would need removed for clearance, but me thinks
you won't need it.

About that, anyone know of a really large diameter lugged tire, that's really thin? Seems improbable, lugged Terra Tires are really thin but they're not real big around but real wide.

Re driving them, find a pattern of rectangular holes, that mesh with the lugs, punch them through and then machine a cogged driver to match? It's up on the ramped up nose, no ground contact.

Bob

Bob,
I was envisioning the driving thru tension, like on a conveyor belt.
The swing arm linky thing would have a couple of turnbuckles to
space out the rear wheel to tighten up the belt.

Yes the tractor tire would be too thick, thinking more about
bicycle tires clipped together using clipper lacing.

Or take an old set of rims, without the tires, weld on some little
pieces of 5/16" dia. rod projecting radially outwards, and punch
your track to match.

I believe that you may find this to be similar to a syphone effect, where the unfolding tension on one side is not much diff than the folding tension on the other - within reason. If you start to wrap it too tight'a Rad then there will be lost power there, but then at the bike speed - prolly not gunna notice it like you would with a mtn sled.


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Think Snow Eh!
Ox