How come Polaris,Can AM,Yamaha and Arctic Cat do not use there High Horse power Sled motors on there ATVs? I,m not talking about there big 1000cc 3&4 cylinder motors that won,t fit, but there smaller 500cc and 750cc 4 stroke twins.

I know there Super High Performance 2 stroke stuff would be out of the question for environmental reasons.

Here is a couple of examples.

The 750cc twin out of the Polaris "Turbo Dragon" is rated at 140 HP.

Even the mellow (For Sled Standards) Yamaha "Venture Lite" 500cc twin is rated at 80HP.


What do the 800cc twins of ATV push? 65hp tops? The 500cc of ATV push 35 HP more or Less?

Why do the use these low powered motors on there ATV,s?

People like me who where sledding before ATVing will know there first experience on a ATV.

I jumped on a 500cc Sportsman and gassed it and thought "Is this thing is a dog,maybe its broken?"

Just in case you think I,m off with my numbers or have no snow here are 2 links.
Yamaha 500 Venture specs

Polaris Dragon specs then click "Engine & Drivetrain.

 

Just a guess,,, but could it be cooling issues? Meaning, sleds are designed for snow and cold climates whereas ATV's are operated in snow and on 100+ degree hot summer days. I have read several complaints about these low powered atv's running hot and can't imagine riding one with double the power on a 100+ degree day. I'm thinking you couldn't get your legs far enough away to keep them from cooking. And, the cooling system would also need a major overhaul to keep the engine temps in the safe range.

 

<div class="FTQUOTE"><begin quote>Meaning, sleds are designed for snow and cold climates </end quote></div>

I thought of that but when we ride in some "March Break" weather you can wear a T-shirt only with no gloves and hat . When we stop you think your getting a sun burn yet the sleds run fine even the hotter running 2 stroke fan cooled models and the 170hp 2 stroke performance sleds.

Wouldn't the engine work harder in a sled also? I can push and roll my ATV around but I can,t budge a sled when its parked.

I,m sure the H.O sleds of 100hp+ would need a rad the size of a Honda civic for the hot summers but a 500cc sled engine of only 50-80 hp should be manageable to keep cool somehow.

You see 600cc street bikes that but out over 100hp idling at a stop light in a heatwave and there radiators are not a ridiculous size.

 

Good points. The only one I can respond to is concerning bikes. Most bikes spend their time on the road at 35mph minimum and usually more like 65 or 75 mph. Whereas atv's probably spend the majority of their time well below the 35mph mark. And, the wind speed difference alone adds a lot to the cooling capacity.

I know,,, I know,,, there are those folks who spend a lot of time at WOT on these things but I don't think their in the majority and that's likely what their designed around.

Hopefully someone will chime in with different ideas or more than just speculation???

 

Most Polaris atvs can be tuned to run a lot better but the factory detunes them to keep them safe for old ladies and morons.

 

<div class="FTQUOTE"><begin quote>Originally posted by: ftwflh

Most Polaris atvs can be tuned to run a lot better but the factory detunes them to keep them safe for old ladies and morons.</end quote></div>


No lack of old ladies and morons on sleds, believe me. LOL

 

I couldn't agree more about morons on both sleds and bikes. I have owned dozens of sleds in my life and a little over a dozen atv's. My guess is that the atv's are indeed built to run most of their time under the 30 mph mark and sleds over the 50 mph mark. I don't know if the tuning has anything to do with the amount of torque the atv's have over the sleds but that could be an issue too. I haven't owned a sled since my 02 zr 800 efi, but I wonder if the lack of v-twin engines is an issue for fit.

 

I just watched a snow cross race last weekend 8-25-07 on
real snow!!! yes real snow!!! at nelson's speed shop (greenville
Mi.) on there outdoor track. It must have been about 80* out.
their were many races run by the same sno-X sleds & I never
saw one sled quit. they also had grass drags with vintage sleds
never saw one quit either. so heat should not be the problem
they just have not wanted to put that much power in a atv frame
because of liability, atv's flip & are not as stabill as a sled chassis
plus sleds did not start out with 150+hp, over many many years have
gotten to that level, with the chassis improvements. As atv chassis
improve & the companies figure out how to defend them selves
in court more power will come. we are already starting to see that.
remember the quadzilla? did'nt liability do it in & set the industry
back for a while.

 

even if you can make it work right chould you imagine how meny people whould kill themselfs with them. quads with 100hp have like +12-16 inch swingarms and crazy drag suspestion.

 

<div class="FTQUOTE"><begin quote>Originally posted by: TLC

How come Polaris,Can AM,Yamaha and Arctic Cat do not use there High Horse power Sled motors on there ATVs? I,m not talking about there big 1000cc 3&4 cylinder motors that won,t fit, but there smaller 500cc and 750cc 4 stroke twins.



I know there Super High Performance 2 stroke stuff would be out of the question for environmental reasons.



Here is a couple of examples.



The 750cc twin out of the Polaris "Turbo Dragon" is rated at 140 HP.



Even the mellow (For Sled Standards) Yamaha "Venture Lite" 500cc twin is rated at 80HP.



they are probably 2 stroke, i dont know why yamaha doesnt put a slightly detuned (so it runs cooler) 4 stroke phazer in the raptor and in the grizz

its only a matter of time before the rotax v990 mille shows up in an outtie i think