Tork
TY 4 Stroke God
Would be tough to get the 3 cylinder above 140 HP without making a complete redesign and adding gear reduction.
Reason I say that is it is 3/4 of the FJR1300 Sport touring 1300cc 4 cylinder motorcycle engine which makes 145HP at about 9K RPM.
You make power 2 ways, displacement and/or higher revs.
To get the 3 cylinder to 1200CC you would have to basically add back in the 4th cylinder (not enough meat in the cylinder walls for much of a bore)
Longer stroke can mean even less RPM, and this was not designed like a hi-rev sportbike motor to begin with.
But with the 4 cylinder 165HP would not be difficult, but honestly I think much more than a 40 lb weight reduction would be pretty tough.
Reason I say that is it is 3/4 of the FJR1300 Sport touring 1300cc 4 cylinder motorcycle engine which makes 145HP at about 9K RPM.
You make power 2 ways, displacement and/or higher revs.
To get the 3 cylinder to 1200CC you would have to basically add back in the 4th cylinder (not enough meat in the cylinder walls for much of a bore)
Longer stroke can mean even less RPM, and this was not designed like a hi-rev sportbike motor to begin with.
But with the 4 cylinder 165HP would not be difficult, but honestly I think much more than a 40 lb weight reduction would be pretty tough.
nate007
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- 1. '06 Apex -twin screw
2. '04 Redline Revolt 800
3. '09 Nytro XTX - twin screw
Far be it for me to interject a theory here....but
If they end up making the Nytro chassis a 160 horse machine, wouldn't they end up killing the sales on the current model Nytro?
If you look at the Apex/Vector series, the Apex outsells it by a good margin, and quite possibly a driving force behind the new style Nytro.
Ask yourelf what you would want if given the option, 138(ish) or 160 horse in the same sled?
I hope for the sake of the customers who like the ergos of the current Apex, they do make the weight adjustments but keep it somewhat of a plush riding trail cruiser/power sled.
If we want light and fast, buy a Nytro.
There are times wen I on't feel like flying through the air and mogul mashing, and I like the raw power of the Apex with a smoother ride. I hope they keep these options open.
One the other hand, if they do make this sled as rumored, is there anybody interested in a mildy customised, low mileage screamer??!!!
If they end up making the Nytro chassis a 160 horse machine, wouldn't they end up killing the sales on the current model Nytro?
If you look at the Apex/Vector series, the Apex outsells it by a good margin, and quite possibly a driving force behind the new style Nytro.
Ask yourelf what you would want if given the option, 138(ish) or 160 horse in the same sled?
I hope for the sake of the customers who like the ergos of the current Apex, they do make the weight adjustments but keep it somewhat of a plush riding trail cruiser/power sled.
If we want light and fast, buy a Nytro.
There are times wen I on't feel like flying through the air and mogul mashing, and I like the raw power of the Apex with a smoother ride. I hope they keep these options open.
One the other hand, if they do make this sled as rumored, is there anybody interested in a mildy customised, low mileage screamer??!!!
grader
TY 4 Stroke Master
the fjr1300 sport touring is just that, a touring machine. the nytro being run in snocross is probably close to 155-160hp now, so getting more hp from a bored out motor is not that hard. the number one reason to go with a three cylinder is reduced weight, one less cylinder, valves, no gear reduction, etc. brp has shown us how far they are willing to go with the xp, taking the hole saw out and swiss cheezing the whole sled. if yamaha is to compete they have to keep getting lighter, but not to that extreme. they could easily turbo a smaller cc tripple(700-800cc) and make 170hp, but dont hold your breath waiting. the other factor to look at is fuel milage. the fuel injection systems are open loop with no 02 sensors. these are currently not needed for the epa regs but could improve mpg easily.it makes me wonder why these sleds all have 30 pound exhaust systems from the factory, and every aftermarket shop in the world can build it with at least the same or more hp, meet the db levels, and be at least half the weight.
This is kind of off the wall but I wonder if the EPS (electric power steering) from the Grizzly has been tried on sleds yet....
QCRider
TY 4 Stroke Master
My opinion is that the 4 cylinder motor is not the future of Yamaha snowmobile motors. It was an easy way into the 4 stroke market, but it is not the ideal setup at all. It's a copy cat world, and if this were the best way to go about powering a sled with a 4 stroke, don't you think we would have seen something similar from Arctic Cat/Suzuki? How easy would it be for them to do the same thing Yamaha did? They have released a few 4 strokes and none of them has been a bike based high revving motor that required gear reduction. In fact no other OEM has gone this route. Why? W-E-I-G-H-T!!
When you start looking at the weight of the motor you have to include the reduction gears as well. The reduction gears while acting as a torque multiplier also reduce fuel mileage. It's basically like driving your 5 speed car in 3rd gear all the time at highway speeds. I love the motor, but they needed something else and they knew it. That's why the evolution of the 3 cylinder motor has happened as it has. There is more than one way to get 160hp from a 3 cylinder that does not include higher revs and reduction gears. Increased displacement is one way, as it forced air induction. Getting an extra 20 - 25 hp out of the Nytro motor with boost would be very reliable and very achievable, but you would be adding weight this way as well. The better option might be to turn it into a 1200 or 1300 cc motor. There is definitely a limit to how much they can bore out that motor, and stroking it won't really increase horsepower, but it is an achievable number for a 3 cylinder non-reduction 4 stroke motor.
Anyway, it's fun to talk about isn't it? I would really like to see it, though I'm not sure it would be enough to get me to blow $11k on a new sled.
When you start looking at the weight of the motor you have to include the reduction gears as well. The reduction gears while acting as a torque multiplier also reduce fuel mileage. It's basically like driving your 5 speed car in 3rd gear all the time at highway speeds. I love the motor, but they needed something else and they knew it. That's why the evolution of the 3 cylinder motor has happened as it has. There is more than one way to get 160hp from a 3 cylinder that does not include higher revs and reduction gears. Increased displacement is one way, as it forced air induction. Getting an extra 20 - 25 hp out of the Nytro motor with boost would be very reliable and very achievable, but you would be adding weight this way as well. The better option might be to turn it into a 1200 or 1300 cc motor. There is definitely a limit to how much they can bore out that motor, and stroking it won't really increase horsepower, but it is an achievable number for a 3 cylinder non-reduction 4 stroke motor.
Anyway, it's fun to talk about isn't it? I would really like to see it, though I'm not sure it would be enough to get me to blow $11k on a new sled.
SledFreak
TY 4 Stroke God
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It's a 3 cylinder, 160, but closer to 170 on the dyno in the Nytro chassis, but the styling on a an Apex. It's the only way they will lose the 40-50lbs.
LJ 452
TY 4 Stroke God
I think they should further refine the Apex chasis by this I mean reduce weight 10-40 lbs. whatever is conceivable without sacrifice. Keep the Apex GT and LTX but can the RTX. Basically the groomed trail versions short and long. But 128" the short not 121", to me 121" is not enough to get the power to the ground and maybe 144" the 136" but with tipped rails. Change the rear exhaust and seat to more of a Nytro but without changing the ergos. This would do a few things, center the mass beter (that rear muffler is heavy), reduce the tunnel to motor compartment flex. and use a common seat to reduce parts. I also think that the straight out the back reduces the feedback to your head as there is no wall for the sound to hit and bounce back toward the operator. I see the Nytro and Apex sharing A-Arms again for durability and less product. I do feel that they should dump the Apex RTX and just have the GT's and ER's. As the Nytro and Phazer are the only RTX's that seem to truley be purpose built. Besides if I want to bash the moguls I would rather do it on the lighter Nytro not the Apex. Just like the Doo RT is not sold as a mogul masher. Can the Apex mash the moguls yes, is it the ideal sled for that No. the Nytro is. Oh and one last thing put EFI on the 3 holer. It's a great motor and if you could bump it up to 125-130 with FI I think you have a winner more so than they already have. Why are they not doing this. Cost? MPG?
06RSRAGE
Expert
How about just drop a SC in a Nytro and just call it an Apex. That would be light weight, powerful, and easy. Plus its already being done and seems to be very durable.
morrisond
Expert
SledderSteve said:
Yes, if we don't see it this year, we'll see it next, apparently only adds 2 lbs.
I would shure like to see aht apex chasis the same with some up grades and more hp.Leave the nytro's for the ditchbangers.Build a muscle sled with more hp.
Laban
Extreme
QCRider said:
The Z1 is HEAVY. The Ski Doo's are underpowered. Then add the fact that the difference in weight between the Nytro engine and the Apex engine is a couple of lbs.
I'm guessing that Yamaha would rather build a 800+cc high-revving triple (Phazer X 1.5+) then the Nytro but the snowcross rules says 1050cc, no gear-reduction.
pro116 said:
Same here!
Kråkan
TY 4 Stroke Junkie
Laban said:
The diff between Apex/Nytro is more then a coupple of kg.. The old vector engine was 3-4kg lighter than the APEX engine and the Nytro engine is supposed to be 3-4kg lighter than the old engine. Correct me if I am wrong..
The vector in Apex chassis was good because the low center of gravity that the smaller engine had. That is also one thing to consider. Not just weight.
One thing that strikes me odd is that there are MORE and MORE talk about weight in this forum when in other forums Yam guys talk about weight not being an issue... :ORC
2008 Nytro RTX
TY 4 Stroke God
If Yamaha comes out with something sick Ill be sure to trade the Nytro in for it.
received my ''horizon newsletter'' last week,one article was about dirtbike new model intro,it said that its always exciting to introduce new models to the public,stay tune for our 2009 snowmobile unveiling,from what i've seen,you wont want to miss that one,this is the exact word from an insider
