Yep, serious cooling system upgrade on an atv that's already oversized and tight for space.
Anyone who's ever ridden a rotax 650 / 800 / 1000 knows how hot these engines run; literally have to move your foot to the outside of the foot well to keep your skin from burning-

 

I don't know they have had 600cc 4strokes since the 1990s with well over 100hp in rice rockets motorcycles in light weight chassis for a long time.

Suzuki GSX-R600 - Wikipedia, the free encyclopedia

Its not like those things have a big heavy clumsy cooling system in any way.
Weight is the enemy to those bikes.
http://www.topspeed.com/motorcycles/...-ar160836.html

600cc at only 412lbs with 120 hp with no heavy anything .
They will run the desert at 100F all day.
I doubt that motor and cooling system cares if its on two wheels or four.

 

Ok, I've had enough.

Everytime I see the title of this thread, I get this song stuck in my head.

It's about time the rest of you suffer too.

 

Hutch sings?

 

I just picked up a polaris 400 explorer 2 stroke to rebuild and play around with my grand kids on there little 4 strokers.
I bought this one because it was so cheap, and years ago i raced 2 stroke dirt bikes and enjoyed the performance of them.
If anyone knows which is the best way to go with my rebuild it would be appreciated. i just want it to be a little hot rod to run around my property with. I live in mississippi where basically it is all flat lands.

 

Check with Rick over at Ritter Cycle. He can get you the parts and the service you're looking for.

 

Agree with Rick Ritter. Sold my 1996 Scrambler 400 and just recently bought it back. Just got done with a top end and Rick set me up.

As to the rest of the thread... I will take my riding weed eaters anyday.

CONS: smoke ( lucky I am going so fast it doesn't bother me. Maybe the four strokes behind me may not like it)
Need top ends rebuilt more often. (I would argue that, but not today)
Like to be run fast. Putting around on them just seems to foul plugs.

Pros: Cheap and fairly easy to rebuild.
Great powerband.
Lighter motor.
Like to be run fast


Something about that 2-stroke sound. Just gets me every time. 1996 scrambler 400, 1998 Trailblazer 250, 2002 Suzuki Lt80.

 

What 4strokes are you referring too because anything from a 400ex on up would hand it to a 400 scrambler, do your buddies know your trying to race them?

 

Those old 2 strokes in ATVs were not serious 2strokes. They never even had power reed valves.

A 440cc liquid cooled 2 stroke should make between 80-90hp.
Even entry level 440cc fan cooled without reeds made 45-50 hp.

Why does it take a 450 4stroke to compete in a 250cc 2stroke motocross race?
A 4 stroke needs a 200cc displacement advantage to compete.

The 125 2strokes race 250 4strokes in their class as well.

Love to see a new 450 4stroke motocross keep up to a old 2 stroke CR500 Honda , RM500 Suzuki RM , KX500 Kawasaki or YZ490 Yamaha.

Same with outboard Motors, a new 90hp 4stroke has the same bulk/Mass as a 150hp 2stroke outboard.

That's why you well never see a 4 stroke chainsaw. By the time it had enough power to cut down a tree nobody could lift it.

 

Uncork an old 250 trail blazer and you'd be surprised how much quicker it could be than the 400ex.