Is a 200 lb dry sled possible?

[AKrider]

Is it possible to build a sled that is similar in weight to a dirt bike? Basically a sled that is the bare minimum needed to transport a guy on the snow but still retains some features so that people would actually want to ride it.

The following things are necessary:
Headlight/tail light
Independent front suspension
A decent seat


I figure a track weighs 50-60 lbs and a motor around 80 lbs. So that leaves 60-70 pounds available for chassis, suspension, steering, transmission.

If the sled had absolute minimal body work, just keep the snow off the clutches, and used a small chassis, maybe 3/4 scale size, is it possible? Do the modern sleds need 163" tracks? Sleds were much smaller and lighter in the 60's and 70's. Most of those sleds didn't use much in the way of common, light weight materials we have now.

 

[manowar]

Anything is possible . I dont know how dependabile it would be or comfortable to ride but possible. And probly expencave as a lambo lol.

 

[RMK-King]

Those carbon fiber chassis they had at haydays could be picked up with 2 fingers,spendy though.

 

[76FOMOCO]

Those carbon fiber chassis they had at haydays could be picked up with 2 fingers,spendy though.

something tells me carbon fiber and trees an not met in this life?
as for 200lbs yes i see it could be done, No you will not have a sled you can put 2500 mountain miles on reliability. As for the older sleds weighing less you do need to look on how well they float in the power......

 

[Going West]

I dont think its possible. Track 55 lbs suspention 35 lbs Motor Chain case 100 lbs Clucthes 20 lbs skis 15 lbs seat 5 lbs. Thats already 230

 

[AKrider]

I was thinking that because the older sleds were smaller, they were also lighter. Today's sleds are much larger and heavier thus they require more track and length for floatation. If the sled is smaller, it can be lighter and won't need as large of a "footprint" to stay afloat. I'm also thinking if the sled was approximately half the weight, it can probably be a single cylinder. If may even be able to lose the chain case and go direct drive like the 1985 Polaris Star.

I'm not sure what a base XP chassis weighs, but it probably isn't very heavy. I think a super light chassis could be made using aluminum.

 

[Nikolai]

I'd really like to try and might for my next build but I think 200 lbs is dreaming. There was some video a few years back of a 330 lb or so race sled with a 990 twin in it...wicked fast. A BD-X gearbox, brake rotor, and driveshaft makes for a very light tranny. With a well thoughtout tube chassis, 153 Powerclaw is mid 40's I think, Ti. suspension, Floats, ect. I think you could have a strong 300ish lb sled. There's a ton of small ways to lose weight.

 

[Transporter]

What does Turboal's tin man sled weigh.Probably more than 200 but its bare bones,There was a thread on it i thought.

 

[ruffryder]

As for the older sleds weighing less you do need to look on how well they float in the power......

I disagree... The older sleds floated rather then trenched. They didn't weigh anything.

I remember when I went from an 80 el tigre fanner to a 97 zr 580. The 580 had a lot more power, but it weighed almost twice as much to. I was blown away at the speed I had to carry in the deep drifts. I could truck a long pretty slow with the tigre.. man that was a nice sled.

Suspension weighs a lot, especially in the front. The old school leaf springs were pretty light, not to mention small motors and only air cooling.

In order to go really light, you are going to have to give up HP, which means giving up some speed.

 

[Nikolai]

What about making a front end with just one larger a-arm on each side? If you look at the older Redline frames, they were pretty minimal in the amount of tubing they used.

 

[89sandman]

maybe a z120??? just add a bigbore kit and your ready to go

 

[snowmanx]

No, I don't think it is possible......Maybe 300#, but 350 seems more realistic.

 

[LRD]

I built a 380 to 385 lb dry 16 X 137 TNT

In order to do that

Light primary clutch 8lbs

16 X 137 X 1.75 track (stock 48 lbs) lightened to 42 lbs

Skid stock 50 + lbs with Ti front arm and moly rear arm I designed and built + Floats - 32 lbs

No oil injection minus 10 lbs

And many other weight reductions minus front cooler = minus 4 lbs etc. etc.

Only other way on this sled to loose any more weight is by going carbon fiber chassis and then weight would be low enough to go down to a 16 X 121 X 2 track (don't know if they have made one yet). This might get another 50 to 60 lbs off for only another 8K Canadian!!!!

The big kicker on the weight loss is the clutches and track, suspension weight components. Track is tuff because driver weight is such a large percentage of total weight that you can't reduce it much without losing flotation and traction, although my T has flotation of a 16 X 154 amazingly but sadly not the traction.

Good Luck

 

[TLKDPROD]

What does Turboal's tin man sled weigh.Probably more than 200 but its bare bones,There was a thread on it i thought.

Around 350-360 dry weight, 4130 chromoly tube chassis with mostly rev components, 16 by 154 track. Amaaazing machine.

You'd have to rethink the whole concept of sledding to get to 200 pounds. MX bikes are averaging that weight... You could go with a lighter motor though and maybe a different transmission system than the CVT to achieve that, smaller track, Carbon fiber chassis & components all over...

Wouldn't want to see the total at the bottom of the sheet !

 

[AKrider]

It looks like LRD was able to take 46lbs off his TNT. That is impressive! I'm not familer with the tube chassis Rev but the weights that have been attained on sleds that are full size is amazing.

So I'm thinking, the easiest way to make something lighter, it is have less of it. Make it smaller. Just like with pick-ups and quads, sleds have grown in physical size over the years. If we look back at the sleds from 30 years ago, they were quite small and pretty light (probably 370 lbs) even though they had fiberglass hoods, steel belly pans, plywood bottomed seats, steel skis, etc. If we look back at the orginal '84 Phazer, it was quite light, under 400lbs for the first model I believe, and used a steel bulkhead that had lots of lightening holes put in it, kinda like an XP. It also had plenty of steel and crap on it that could have been stripped off for even more weight savings.

Seeing what components weigh, I wonder how much heavier a track and skis plus their suspensions are over a dirt bike's tires, wheels and front and rear suspensions? Perhaps I should be using a sport ATV's weight as a target instead? Back in the mid 80's, the original '85 Suzuki Quadracer 250 was listed at 293 lbs dry. It gained weight every following model year.

It seems like a 300 lb sled could be built without using exotic materials. I'm thinking the motor would have to be a single cylinder. The track no longer than 137", single ply. The a-arm front suspension could use a tubular front clip like a Phazer and Nytro. The tunnel would be conventional. The rear skid would need to be lighter than current designs, but it could also be built lighter since it would be dealing with less weight than a standard sled. It would be interesting to know what kind of weight savings could be had with a single cylinder motor over a twin? There aren't too many guys wanting more power from their CRF 450's or an old CR 500 two stroke dirt bike.

 

[Going West]

Whats the point of taking all this weight off if you going to have a smaller motor and a smaller track. Have a sled thats real expensive and not as reliable to go the same places as you did before. Kind of seems like a wast of time to me. Dont see too many people asking for less power and less floatation. Lighter is fun and easier on the body but there is a balance between thoretical and reality, and I think the newer sleds strike a good balance when modded correctly.

 

[ruffryder]

I think sometimes, more power makes you riding area's less fun as the amount of challenge decreases.

I have heard many times from people that have to get back onto older underpowered sleds, how much fun they have on terrain that is boring on regular sleds...

Something to think about.

 

[winter brew]

Helium!

 

[revelized]

Lose water cooling!! its freezing when we run these things anyway... just look at the guys way up north in canada running polaris 550's for ever and ever and they just keep on tickin

heres my indy lite 488

 

[turboless terry]

Not a chance! You couldn,t do it with a single cylinder engine. It would be awesome but everything on a snowmobile is twice as heavy.