I have read many times in this forum about Polaris being able to make a 175 H.P. snowmobile but not an ATV. I am no expert here but have spent a fair amount of time on a sled (snowobile)and my ATV's in the snow.

Seems to me the major difference in snowmobiles and ATV's in terms of acceleration is traction. Here in BC Canada most sled heads are into hill climbing, seroius powder and steep slopes. When you are pushing yourself and your sled to it's limits you need an incredible amount of track speed to keep yourself floating on top of the snow. That 2.5" track is turning at who knows what M.P.H. but you are only moving at 25 M.P.H if you are lucky near the top of your climb. You really need that 175 HP in a sled. Me thinks that there is a seroius loss of H.P. to ground on a sled, so much slippage when the track is turning alot faster than you are actually moving.

Not to say that a quad not need be that fast but I think there is a whole lot more wheel to ground traction on an ATV in relation to an sled. Also a sled must weigh almost double than my 400L.

On my last trip out in the snow, my 400L felt like a Trailboss 250 in the deep stuff. Too much wheel spinning.

I have ridden some very fast sleds, ones where you can snap the throttle and pull the skis upright. Quite a rush no doubt, but it just seems to me that 175 HP in an ATV is suicide.

I am not claiming to be right or by any means an expert. I just wanted to get a new topic of interest started and see what sort of ideas you folks have.

Keith

 

sleds require more Hp than ATV's because the track has much more drag than the powertrain of a quad. if u had a 175hp quad u would kill yourself very fast.

a sled with 40-50hp would be a slug, unlike a quad.

i dont think any polaris sled is 175hp, i think the 800XCR is only 155.

later
jon

 

40 to 50 hp sleds would easily hit 80 mph and give the quickest current quad a good run .A 370 fan cooled twin ski-doo hits 60 mph with only 35 hp and a 400 liguid cooled can push 50 hp.The guy above was talking about deep powder riding but most riding is done on groomed trails and lakes where traction loss is close to nill without adding studs on the track.The entry sled now a days would give the fastest sled of the ealy 1980s a run for there money and the fastest sleds now are just at the point of nuts.So far this year there has been 17 deaths in Ontario,30 in Michigan and 40 people died in Wisconsin and that is just normal(got those numbers from the news last week).Sleds ride on checked out groomed trails and frozen lake while we may ride on the same trails when the snow is gone the rocks,fallen trees and holes are not buried under 3 ft of packed groomed snow.

 

i agree with u 3TV, but would u want to ride on the same trails with a idiot on a 200hp sportsman,or even a 75hp sportsman?

i cant even imagine what kind of CV joints and Powertrain u would need to handle that power. if they get any more powerfull then we will have to have a license to ride them.

later
jon

 

You have to include the rider weight in your equation (unless your bike is remote-controlled). I think it would be fair to add 200# to each. This gives your CR weigh 428. With 70 HP that leaves your Power to weight of 1 to 6.1. Using this same formula puts The Sp at 38hp and weight with rider at 897#, leaving a power to weight of 1 to 23.6, still about 4 times the power for the weight, meaning the Sportsman would need over 150hp to compare. Also, a person could argue that most people on a CR500 are in prety decent shape (rode on once, scared the bejeezers out of me - I was used to an XR 250 & 350) whereas the Sportsmans are often ridden by people who are, how do you say, gravitationally challenged.
Just one thing...would you want to share the trail with a Sportsman that had the performance of a CR500? Some of the manicacs I see are bad enough, expecially when you consider they have half a ton rolling along sometimes (very big dudes, or with a passenger).
Power to weight, and handling are BIG factors in performance. That is why a 'puny' 250R will do circles around a 'big' 500 scrambler ON THE TRACK. Lighter, more nimble. I think instead of trying to make a 150 HP Sportsman, they should go the other way, and build a quad with the ride and handling of the Sportsman, and try and get them to lose 100# or more. Less weight would do a lot to put more H in the HO.

 

If Polaris put a XC 500 in a Sportsman and even add 100 more pounds it would roll along the ground at over 100 mph and get there fast.You just would have so much power that weight will not even matter.It is easier to roll a 1000lb along the ground than push a 500 lb sled over the ground, snow or not.

 

true tim but do u know what kind of fuel economy u would get??? it would be a big gas hog. that 5.25gal tank wouldent last long.
it would also be hard to cool it, that two-stroke makes more heat than a four-stoke.

later
jon

 

I think the motor would get better milage in a guad than in a sled. The sled does not free wheel like a quad on wheels and unless you live near the salt flats the throttle would not get open up like on a sled.A 500 sled on a bad day gets 10 mpg so a 50 mile range at the worst on a quad is reasonable but it will do better than that.Polaris would have to add weight with a much larger Radiator and fan but the new motor would not notice it. Polaris real reason to never to make a XC500 powered Sportsman or Srambler is that to many people would die to quickly on them.

 

As a former sledhead, still am in spirit, but not alot of snow around Phoenix, I bought my first ATV looking for the sled experience--Auto trans, and trying to re-live all the great times I had growing up with snowmobiles in Minnesota. I love riding my Kodiak, and I have ridden some faster machines, but they could never compare to the "suck your eyeballs back in their sockets" acceleration of the sleds I used to ride. So I too wondered why someone couldn't take a liquid cooled snowmobile type engine with about 50 to 60 hp and couple it with an auto trans, 2 wd and it would be a blast to ride. Obviously, if a two stroke twin has enough low end torque to power a sled, there would be no bogging with a quad.
True, with a sled you get to be a lake racer on the frozen ponds, so 75-80 mph is not really a problem--no obstacles. I wouldn't want to go that fast on a quad--but I think the 0-40 or so acceleration improvement would be lots of fun.