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Small-Doo M
- Thread starter Ben550
- Start date
Cool machine!
Seems to tractor around pretty good on the limited HP.
Details on the build?
Seems to tractor around pretty good on the limited HP.
Details on the build?
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Thanks!
Home made aluminum frame, Fiber carbon panel. Engine positioned low and glued on the front of the tunnel, very advanced driving position like the most recent snowmobiles. The rear suspension is home made for light possible.
Engine technology like Honda GX390 but 460cc, forged components, cam 306, ported, mikuni TM34, variable timing. 36HP 40lbft.
Weighs 300lb with gas so it weighs 200lbs less than a regular wet mountain snowmobile (weight that is mostly subtracted from the front) with a similar track (153 '' * 2.6 ''). It has a traction and incredible buoyancy at low speed. He can stop and start up hill without digging a deep trench. The high speed traction is less than that of a mountain snowmobile because of the very big power difference, but I use it mainly in the forest where it is difficult to go fast.
There is no more light sport utility snowmobile, it has the weight of an Elan with a mountain track and 3 times more torque.
Home made aluminum frame, Fiber carbon panel. Engine positioned low and glued on the front of the tunnel, very advanced driving position like the most recent snowmobiles. The rear suspension is home made for light possible.
Engine technology like Honda GX390 but 460cc, forged components, cam 306, ported, mikuni TM34, variable timing. 36HP 40lbft.
Weighs 300lb with gas so it weighs 200lbs less than a regular wet mountain snowmobile (weight that is mostly subtracted from the front) with a similar track (153 '' * 2.6 ''). It has a traction and incredible buoyancy at low speed. He can stop and start up hill without digging a deep trench. The high speed traction is less than that of a mountain snowmobile because of the very big power difference, but I use it mainly in the forest where it is difficult to go fast.
There is no more light sport utility snowmobile, it has the weight of an Elan with a mountain track and 3 times more torque.
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All ready 2 feet of new snow fell last week, not counting that it had fallen quite a bit the previous weeks. It was just above zero with sun, so the snow was often sticky, it would have been too easy if it had been dry.
A little side hill, I'm not good in this discipline, but with this machine we can go very slowly, no need to give the gas to dig the caterpillar, no need to shift on one leg and the other in the air, not even need to steer.
Taken for the first time with the M, the disadvantage when it does not move more is that it is really deep hollow. As the rear bumper is nearly 3 feet below the surface of the snow, and the bumber is a good 38 '' above the underside of the track, the rear of the track is just under 6 feet under the snow and it there is still no land in sight!
When I fall down the snowmobile in virgin space, its calle mid breast.
A little side hill, I'm not good in this discipline, but with this machine we can go very slowly, no need to give the gas to dig the caterpillar, no need to shift on one leg and the other in the air, not even need to steer.
Taken for the first time with the M, the disadvantage when it does not move more is that it is really deep hollow. As the rear bumper is nearly 3 feet below the surface of the snow, and the bumber is a good 38 '' above the underside of the track, the rear of the track is just under 6 feet under the snow and it there is still no land in sight!
When I fall down the snowmobile in virgin space, its calle mid breast.
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https://www.youtube.com/watch?v=slzxUXQjC2o&feature=youtu.be
Despite the limited power compared to the huge track, the engine climbs to 5600RPM initially and holds its 5200RPM in the coasts with deep and wet snow. (5200RPM is the speed at which I measured the engine at its best performance) It has a little more torque than the 600ACE.
It would take a wiper on the gopro, the passages normally cleared are no longer at the height of the snow
Despite the limited power compared to the huge track, the engine climbs to 5600RPM initially and holds its 5200RPM in the coasts with deep and wet snow. (5200RPM is the speed at which I measured the engine at its best performance) It has a little more torque than the 600ACE.
It would take a wiper on the gopro, the passages normally cleared are no longer at the height of the snow
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What shocks are those?
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The front are no name, but They are very light and they do the work. The central shock is a Fox Float 3, it is he who is the most important for my use.
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I made a table of data. The first 2 are series snowmobiles that I lightened more than I could with a budget raissonable.
The next 3 are snowmobiles made from scratch.
The last 4 are small sport utility snowmobiles for comparison
The next 3 are snowmobiles made from scratch.
The last 4 are small sport utility snowmobiles for comparison
I made a table of data. The first 2 are series snowmobiles that I lightened more than I could with a budget raissonable.
The next 3 are snowmobiles made from scratch.
The last 4 are small sport utility snowmobiles for comparison
Factor your power to weight ratios with a rider and see how that looks.
Your builds are a testament to the virtues of lightweight.
While it would require major changes to the design & defintely add weight I can't help but think that a 2 cylinder fanner would be the ultimate powerplant to improve performance and overall, thrill factor.
Something like a Polaris Pro X 440 engine..........:face-icon-small-hap
While it would require major changes to the design & defintely add weight I can't help but think that a 2 cylinder fanner would be the ultimate powerplant to improve performance and overall, thrill factor.
Something like a Polaris Pro X 440 engine..........:face-icon-small-hap
I made a table of data. The first 2 are series snowmobiles that I lightened more than I could with a budget raissonable.
The next 3 are snowmobiles made from scratch.
The last 4 are small sport utility snowmobiles for comparison
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Thanks!
Making a snowmobile with a cold fan 440 from scratch, I could probably get a weight half way between my very lean MXZ and the Small-Doo M in the best case, I would need a gas tank bigger. As a 440 cold fan a carburetor makes about 40HP, it would take changes to have a good power difference. The pro X 440 was announced how much?
I want to make my snowmobiles to get something different from what exists, which has some very great benefits in some specifications, and some disadvantages in others. Which provides a different fun factor, being able to stop and start climbing without digging a trench has one. Driving a snowmobile under 300lbs in small, winding, narrow trails is a pleasure you do not have with a normal snowmobile. I would still have more power to beat my MXZ in all conditions, but no more weight.
https://www.youtube.com/watch?v=0UK30MXD7HA&t=4s
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Another snowmobile made from 0 (even the track) and produced to some copies, manufactured by a Quebecois. They are light and robust, they have extreme flotability.
https://www.youtube.com/watch?v=6OlTY9hfzyc&t=418s
https://www.youtube.com/watch?v=6OlTY9hfzyc&t=418s
Definitely a different experience.
You should try snowbiking........ in the same terrain you ride you would have a blast.
My axys has a power to weight of 3.71 lbs per hp.
With rider.
My ktm sx450 (62 hp) with Timbersled aro 120 (and rider) is 8.2 lbs per hp.
Dry weight of bike and kit is 310#
Sent from my iPhone using Tapatalk Pro
You should try snowbiking........ in the same terrain you ride you would have a blast.
My axys has a power to weight of 3.71 lbs per hp.
With rider.
My ktm sx450 (62 hp) with Timbersled aro 120 (and rider) is 8.2 lbs per hp.
Dry weight of bike and kit is 310#
Sent from my iPhone using Tapatalk Pro
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Definitely a different experience.
You should try snowbiking........ in the same terrain you ride you would have a blast.
My axys has a power to weight of 3.71 lbs per hp.
With rider.
My ktm sx450 (62 hp) with Timbersled aro 120 (and rider) is 8.2 lbs per hp.
Dry weight of bike and kit is 310#
Sent from my iPhone using Tapatalk Pro
Yes, but my construction is not meant to beat big-engine snowmobiles with small snowblower engines in terms of horsepower. It is the buoyancy (the blue number) which is the most important for my application. And at this level I have done well, a lot better than snowmobiles in this category (light mechanical snow shoes) and not just a little. It is this specification that allows you to go slowly in the undergrowth, to stop and leave anywhere without digging.
The PRORMK 155 '' version is 0.58 lbs / in2, the best mountain snowmobile, but its weight at low speed is mainly on the front. The snow bike with its little track is 0.72 lbs / in2. The manufacturers are already doing what is best in terms of power ratio (unless you add a turbo and lose all reliability) hands in terms of buoyancy for small utility snowmobiles, they are in the field.
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Climb climbs and even climbs, despite the low speed approach.
It can be seen that the power line is filled with deep traces of mountain snowmobiles
I scratched with the Small-Doo M, it has more traction and strength than it needs, but the narrow and light front makes it unstable in some curves and steep climbs. The little grader raises the front of the snowmobile.
https://www.youtube.com/watch?v=SLmA1DRw2-I
It can be seen that the power line is filled with deep traces of mountain snowmobiles
I scratched with the Small-Doo M, it has more traction and strength than it needs, but the narrow and light front makes it unstable in some curves and steep climbs. The little grader raises the front of the snowmobile.
https://www.youtube.com/watch?v=SLmA1DRw2-I
The floatation number is really a good indication with a sled.
You’d be surprised what you can crawl along through (deep) with a snowbike due to the ski packing a trail and not having any running boards or belly pan to get high centered on.
Then when hills are involved nothing can slow sidehill like a snowbike.
An enduro style bike with a 136” track kit will float and easily traverse steep terrain in the deep and or very deep.
Please be clear I’m in no way disparaging your machines just offering an alternative. (That handles sidehilling in its sleep) lol.
Build your own light weight version?
Would only be a minor change to single ski.
Sent from my iPhone using Tapatalk Pro
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I did not have the opportunity to see snowbikes on the same field as me. But I have said that it is difficult (very physical to drive) I'm not a bike guy (I'm mountain biking in the summer) so it would be more difficult for me.
Certainly the side hill is naturally much easier than with a snowmobile.
I already thought I might build a smaller, less powerful (and less expensive) version to begin with.
What are the ability to climb at low average speed between trees of your SX450 vs RMK vs 800R! custom snowbike?
The sx450 does the best for slow speed climbing. (Zigzag)
For what it’s worth the snowbike is by far the least amount of physical effort required to ride. Easily maneuver through tight trees without having to hop back and forth across like a sled.
The 800r snowbike was super awkward to ride (too much rotating mass) so i’m Messing around with a Yamaha R6 powered snowbike. (Much better)
Mostly similar to a sled though speed and momentum are your friend.
And boy does that streetbike fly! Lol
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