Power to Weight Ratio: Four Stoke vs. Two Stroke

[m1kflyingtiger]

Yes, but that's standard for just about any acceptance testing for any internal combustion engine since the 1970's. Remember when they started sealing off jet adjustments in carburetors.......

I was just making the point because we tend to compare things with what most people will run not what's approved.

Where I ride ,the rated, approved, and waranteed sled, the pro is 3.28 lbs or hp and the turbo Yami is 3.38 lbs per hp.

Sure you can turn the Yami up but then it's not covered by factory warantee or EPA tested and we are no longer comparing apples to apples(ish...it's still a $13k sled with a $2k upgrade compared to an $11k sled bone stock)

Also for some reason we keep comparing the lightest 2 stroke to the lightest 4 stroke, not the comparable 2 stroke. IMO we need to be looking at its 2 stroke brother for direct apples to apples comparison. The m8 is the same sled without the 4 stroke "heavy" heart. It weighs in at 569 lbs ready to ride and makes right at 160 hp. That is 3.56 lbs per hp(2013 HCR 153" - sorry I don't have ready to ride weights of a '15 162" M8000, but should be close enough for the point I'm getting to)

That tells us we are there with 4 stroke technology. Sure it can always get lighter and better, but you could put the motor in a lighter chassis (ie pro) and knock another 50-60 lbs off of the sled, but power to weight, chassis for chassis, comparing motor packages, ready to ride the 4 stroke is better.

CatRpillar- I don't remember those days...I was born in '89 and have days I wish the EPA wouldn't have ever been created. I feel they go to far (pretty much everything they mandate on the exhaust side ie DPF and CAT's), but also they are the reason we have the cool technology we do today such as direct injection (well fuel injection actually) and lightweight 4 strokes. Get the good with the bad and make the best of it I guess.

 

[CatRpillar]

Like your reply. That said, I know this thread is about power to weight but I think we'd both agree that there is much more to matching a sled to a rider than just that, and that riding conditions and preferences have a huge role to play, otherwise we'd all be riding drag sleds.

To expand on things:

1. I love these threads. Lots of opinions about whether oil should be full or empty, etc. Or at least on 2s threads as there isn't much arguing about oil in your 4s! That said, full of gas and coolant, as well as the rider being part of the equation. Otherwise I'm going to claim by quadcopter has a better power to weigh ratio.......

2. So, let's compare the omnipresent Polaris RMK with a stock and MPI turbo Viper. I'm not going to get locked into getting the numbers exact but I'm sure others with OCD will chime in.

Polaris - 420 dry, 60 of fuel, 150hp, 10 of coolant, 30 of snow/ice, 190 for the rider, dressed

At sea level - 710# and 150hp - 4.73#/hp
At 6,000' - 710# and 123hp - 5.77#/hp

Viper - 525 dry, 60 of fuel, 135hp, 10 of coolant, 30 of ice/snow, 190 for the rider, dressed

At sea level - 815# and 135hp - 6.04#/hp
At 6,000' - 815# and 111hp - 7.34#/hp

Viper with 190 hp turbo, same otherwise for weight but add 25 (40 add 40 but subtact 15)

At sea level - 840# and 190hp - 4.42#/hp
At 6,000' - 840# and 190hp - 4.42#/hp

What can I deduce from this, ignoring a whole bunch of other factors?

The Polaris will boondock best of the three because it has lighter weight, no matter the elevation
The turbo will out accelerate and outclimb the other two no matter what elevation.
The stock Viper will be the most reliable but the other two will out perform it in most situations.

So why would someone like myself pick, and leave stock, at least for now, an XTX?

1. I want to try a 4s.
2. I don't ride like I used to, but I still ride, and I don't do deep snow conditions where the other two sleds would excel.
3. If I really like the sled I can easily add big power and keep reliability.
4. Because after 45 years of smelling like 2s oil I want to smell better. lol. Seriously, all my buds still ride 2s so I can still get my fix if I want to smell like that, although the Doo's are better now but sound like tractors at idle....

Most important? Ride, pick what you want, modify it how you want, and again, ride.

 

[icr]

Here's my take on it.

This thread is stupid.

I appreciate the research people have put into it and there's some cool info here but....no one buys a four stroke that cares about power to weight ratio. Done. Moot point. It's over.

Stock for stock a pro has a better ratio. Turbo to turbo the pro wins again. Mod for mod dollar for dollar doesn't matter, pro wins.

That's why the pro has 50% of the mountain market and Yamaha has 3%. Those are real numbers, how's that for quantifying it?

Here's why people buy four strokes. Reliability.

Stock, can't beat them.

Turbo'd, can't beat them.

I had a turbo four stroke with a power to weight ratio of 1hp per 2lbs. That's way better than a pro, but I couldn't get it unstuck by myself. It was fun to ride, but in a different way. Ride what you enjoy but quit making a comparison you can't win.

 

[BigFish BC]

there is way to many peaple hung up on dry weight or wet weight or hp to lbs,yes they are important in some way but are not the total equasion.i dont really like the poo chassi it dont fit or work for me so why the hell would i buy it?
because burant rides it?because its the lightest.i bet 30-40% of guys ride the poo because burant does or because its the lightest,not because it fits them & works for them.i have been riding sleds since they were allot heavier,allot less power & allot shorter tracks & yet i still had fun,funny how that could be possible.i think allot of you guys need to learn how to have fun instead of whining about what other peaple ride

 

[christopher]

IMO we need to be looking at its 2 stroke brother for direct apples to apples comparison. The m8 is the same sled without the 4 stroke "heavy" heart. It weighs in at 569 lbs ready to ride and makes right at 160 hp. That is 3.56 lbs per hp(2013 HCR 153" - sorry I don't have ready to ride weights of a '15 162" M8000, but should be close enough for the point I'm getting to)

That tells us we are there with 4 stroke technology.

That is a VERY good point!

 

[christopher]

Here's my take on it.

This thread is stupid.

I appreciate the research people have put into it and there's some cool info here but....no one buys a four stroke that cares about power to weight ratio. Done. Moot point. It's over.

Stock for stock a pro has a better ratio. Turbo to turbo the pro wins again. Mod for mod dollar for dollar doesn't matter, pro wins.

That's why the pro has 50% of the mountain market and Yamaha has 3%. Those are real numbers, how's that for quantifying it?

Here's why people buy four strokes. Reliability.

Stock, can't beat them.

Turbo'd, can't beat them.

I had a turbo four stroke with a power to weight ratio of 1hp per 2lbs. That's way better than a pro, but I couldn't get it unstuck by myself. It was fun to ride, but in a different way. Ride what you enjoy but quit making a comparison you can't win.

Too bad he is posting Blind and can't read anything we are saying here.

 

[icr]

Do you really believe my status as a non paying member invalidates my opinion or affects my ability to see your snide remarks?

 

[BigFish BC]

Here's my take on it.

This thread is stupid.

I appreciate the research people have put into it and there's some cool info here but....no one buys a four stroke that cares about power to weight ratio. Done. Moot point. It's over.

Stock for stock a pro has a better ratio. Turbo to turbo the pro wins again. Mod for mod dollar for dollar doesn't matter, pro wins.

That's why the pro has 50% of the mountain market and Yamaha has 3%. Those are real numbers, how's that for quantifying it?

Here's why people buy four strokes. Reliability.

Stock, can't beat them.

Turbo'd, can't beat them.

I had a turbo four stroke with a power to weight ratio of 1hp per 2lbs. That's way better than a pro, but I couldn't get it unstuck by myself. It was fun to ride, but in a different way. Ride what you enjoy but quit making a comparison you can't win.

it amazes me how many of you guys are basing your opinions on apexs & nytros + all your # are based off old # you have no idea what yammi will sell.
i 100% agree stock for stock pro wins
mod turbo been around both allot & depending on what condition are or where your riding i will give them a draw lower snow or spring condition the pro wins deep deep pow the yammi will pull away with nasty track speed.
oh & how could you not get your powerhouse custom sled unstuck by yourself, i have had apexs buried & got them out by myself. please let keep things real these 4s are heavy enough without exaggerating things.

 

[icr]

Market share has to be based off previous years, not what they might sell this year. I agree Yamaha will claim more of the market this year because the viper is a much better sled than the nytro, but we won't know what percent until next year. And I doubt it will be more than a few percent, why compare to the market leader? If you want the most popular sled then buy it, don't try to convince everyone else to buy what you bought

As for getting my powerhouse chassis unstuck on my own, it weighed 550lbs dry and had a 174x3. Either you're much stronger than me or we have different ideas of being stuck.

 

[icr]

I'm not sure how but somehow I feel as though I'm being attacked for being anti-Yamaha. I like Yamaha. I love their engines. I think they're headed in the right direction with the viper and could easily own the mountain market with a little more commitment. Although I see many faults with their past chassis and don't think they're anywhere near being a market leader now at least they're competitive and that was the point of my first post. Stop trying to be first place over night and just be happy that Yamaha finally has a competitive platform for the first time in about 15 years. If you bought a viper that's great, but don't try to justify your purchase by comparing it to a pro. They are completely different machines meant for different consumers.

 

[CatRpillar]

I'm not sure how but somehow I feel as though I'm being attacked for being anti-Yamaha. I like Yamaha. I love their engines. I think they're headed in the right direction with the viper and could easily own the mountain market with a little more commitment. Although I see many faults with their past chassis and don't think they're anywhere near being a market leader now at least they're competitive and that was the point of my first post. Stop trying to be first place over night and just be happy that Yamaha finally has a competitive platform for the first time in about 15 years. If you bought a viper that's great, but don't try to justify your purchase by comparing it to a pro. They are completely different machines meant for different consumers.

Agree that comparing the two is fruitless. Different buyers with different expectations. But, this is a 2s vs 4s hp to # thread so the Pro is the benchmark in that category for stock. The door and cat aren't far off though. I love Yammie for their persistence though and when all sleds switch to 4s we'll have them to thank just as we do the others for development in weight etc

 

[christopher]

If you bought a viper that's great, but don't try to justify your purchase by comparing it to a pro. They are completely different machines meant for different consumers.

But I DID compare it to the Pro.
And I did NOT like the Pro, so I bought the Yama-Cat Viper instead.

 

[prorideupper800]

Two Stroke vs. Four Stroke

Here's the Long and short of it you buy a light weight Two Stroke so when you get stuck it don't take a D-8 Cat to get you out, the Yamaha's are great reliable sleds but with out a Turbo are gutless even in the Midwest at 1500 ft. My 2013 Pro is Super easy to get unstuck no matter the situation. I do a lot of boon docking by myself and that's the sled for me.

 

[BigFish BC]

I'm not sure how but somehow I feel as though I'm being attacked for being anti-Yamaha. I like Yamaha. I love their engines. I think they're headed in the right direction with the viper and could easily own the mountain market with a little more commitment. Although I see many faults with their past chassis and don't think they're anywhere near being a market leader now at least they're competitive and that was the point of my first post. Stop trying to be first place over night and just be happy that Yamaha finally has a competitive platform for the first time in about 15 years. If you bought a viper that's great, but don't try to justify your purchase by comparing it to a pro. They are completely different machines meant for different consumers.

iam not attacking you,you are in the yammi forum not the poo forum & i dont care what you ride & i have not once told anybody they should buy one.4s strokes are not for eveyone, i always tell peaple to ride befor they buy.i dont need to justify anything i buy or ride but to myself,something all the 2s guys need to get through there heads.the only peaple trying to justify there purchase are all the non yamaha owners in this thread bashing something nobody has any time on.i have no problems with peaples opinions we all have one but iam real tired of the over exageration, but hey thats just my opinion.

 

[christopher]

Here's the Long and short of it you buy a light weight Two Stroke so when you get stuck it don't take a D-8 Cat to get you out, the Yamaha's are great reliable sleds but with out a Turbo are gutless even in the Midwest at 1500 ft. My 2013 Pro is Super easy to get unstuck no matter the situation. I do a lot of boon docking by myself and that's the sled for me.

Gutless is probably an over-statement, but them NO ONE here is even discussing riding a Viper without a Turbo on it, so its yet again just another Bull-Crap argument that falls flat on its face.

And then there is the never ending mantra of getting unstuck.
Many, its the strangest thing.
But I have been riding 4 yamaha's for the last 5 years, and I just don't seem to recall every having to call in a D-8 dozer to get unstuck.

What I seem to recall is that when I got stuck on my Nytro I had to move some snow from in front of it, and then have one of my riding partners give a tug on the front ski and away we go??

 

[stingray719]

Here's the Long and short of it you buy a light weight Two Stroke so when you get stuck it don't take a D-8 Cat to get you out, the Yamaha's are great reliable sleds but with out a Turbo are gutless even in the Midwest at 1500 ft. My 2013 Pro is Super easy to get unstuck no matter the situation. I do a lot of boon docking by myself and that's the sled for me.

You may see this Viper that belongs to a friend of mine in the UP this year as he is from your area. Pull up and try him he likes to race, and his sled is NOT boosted and does 109mph in the 1/4 mile at 11.2 seconds. Come back and let us know how that goes....

 

[stingray719]

Gutless is probably an over-statement, but them NO ONE here is even discussing riding a Viper without a Turbo on it, so its yet again just another Bull-Crap argument that falls flat on its face.

And then there is the never ending mantra of getting unstuck.
Many, its the strangest thing.
But I have been riding 4 yamaha's for the last 5 years, and I just don't seem to recall every having to call in a D-8 dozer to get unstuck.

What I seem to recall is that when I got stuck on my Nytro I had to move some snow from in front of it, and then have one of my riding partners give a tug on the front ski and away we go??

But we have an RMK guest sled and it is not that light or that powerful......WAIT! I just realized it is a 2006 RMK and there are big changes from that model to now! **snickers**

Christopher isn't it funny how the haters keep insisting this Yamaha is the same as all the previous?

 

[m1kflyingtiger]

We did have a nyto die (cracked oil resivoir) on us way back up some technical stuff one day. Actually in the place where that vid of BOOSTED on the nypex was taken. It was a hillatious trip out. We only had enough rope to tie two sleds to it and the snow was too deep and fluffy. It didn't matter how much we packed it we couldn't get enough traction to tow it out. Ended up with 6 of us on the rope pulling it up the hills and coasting it down till we got to the flats.

As much as we give him chit for it being a pig, it wasn't any harder than if it had been my pro, or my buddies cat. At that point, with 6 guys on it, each person has an extra 16 lbs of work is all.

This thread has kinda turned into a pro vs viper thread, which is unfortunate because there was a great topic in here. I've ridden them back to back. Same day, same snow, pull a line on my pro, pull one one the turbo viper with dealer installed 180 hp turbo, and there was nothing I could do on my pro that I couldn't on the viper. Actually there was more the other direction, because I know I couldn't haul a sled with a moose in it from my cabin with my pro. It would crinkle the tunnel and overheat the sled. It pulled like a freight train and the only limitations I found to it was I was paranoid of dropping a prototype 2015 sled off a rock face.

In comparison to its cat brother it rode more balanced, more predictable, more eaisally maneuverable (or "flickable" for those pro bros not into proper English), and more responsive. It is 100 lbs heavier than a pro. That being said the m8 is 54 lbs heavier than a pro and the xm is 45 lbs heavier than a pro. (RTR weights) there is a bigger weight gap from the pro the the m8 than from the m8 to the viper.

 

[motojunkie101]

Gutless is probably an over-statement, but them NO ONE here is even discussing riding a Viper without a Turbo on it, so its yet again just another Bull-Crap argument that falls flat on its face.

And then there is the never ending mantra of getting unstuck.
Many, its the strangest thing.
But I have been riding 4 yamaha's for the last 5 years, and I just don't seem to recall every having to call in a D-8 dozer to get unstuck.

What I seem to recall is that when I got stuck on my Nytro I had to move some snow from in front of it, and then have one of my riding partners give a tug on the front ski and away we go??

I rode my nytro stock for a year and another year with just a skid swap. You know, not only did I survive I had fun once I got it dialed in for me. It ran with mod 700s which was plenty good for me at the time. You can ride them stock, just don't expect to run with an 800 and you will be happy.

My m8 153 limited feels just as heavy when it is stuck. Seems like a moot point to me. I will say 240hp does get stuck less often though!

 

[christopher]

This thread has kinda turned into a pro vs viper thread, which is unfortunate because there was a great topic in here. I've ridden them back to back. Same day, same snow, pull a line on my pro, pull one one the turbo viper with dealer installed 180 hp turbo, and there was nothing I could do on my pro that I couldn't on the viper. Actually there was more the other direction, because I know I couldn't haul a sled with a moose in it from my cabin with my pro. It would crinkle the tunnel and overheat the sled. It pulled like a freight train and the only limitations I found to it was I was paranoid of dropping a prototype 2015 sled off a rock face.

I suppose that is kind of MY FAULT as that was the sled I chose at the very beginning to make the comparison against.

Me personally, I don't care all that much for the Pro.
When SnoWest did the Deep Powder Challenge a year or two back I got a full day on all 3 of the 2S Mountain sleads. At the end of the day I clearly chose the Arctic Cat as my personal favorite. So I have admit, i was NOT all that unhappy with Yamaha picking Cat to partner up with. I LIKED how the cat rode and handled. It seemed "More Attached" to the snow than the Pro did.

I always felt like the Pro was snowboarding ontop of the snow. I never felt really connected to the terrain. Maybe that just comes from too many years on a Nytro and being overly connected??

Either case, it might be the lightest, but it was certainly not my favorite.