Warning, -16 late build Viper turbo breakdowns, bad rods.

[Studroes144]

Other than quicker revving why did the rod get shortened? I've always heard and been told a shorter rod will have more side force on the piston throughout the stroke and I'm sure it affects the rod as well.

 

[cannondale27]

So they can just change piston for lower compression is my guess.

 

[cannondale27]

Or maybe they wanted it to rev a bit quicker. We are 100% sure the stroke of crank stayed the same?

 

[cannondale27]

Is a good question Studroes. Normally stroking crank is only reason anyone shortens the rod.

 

[shagman]

Or maybe they wanted it to rev a bit quicker. We are 100% sure the stroke of crank stayed the same?

Had to or it wouldn't be 1049.


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[Studroes144]

Used to be pretty fond of sport wheelers several years ago (banshees) and built a stroker engine that used the stock rod length, aftermarket crank and rods so they were strong, never had any engine problems but every year it needed to be bored with new Pistons cuz it would get low on compression, cylinders would get wore to where it showed the extra side force from the longer stroke and standard length rods. Looks like this new crank is the same layout but shorter rods can give it that same affect from added side force, if that's the case then I'd say there could be several possible failures when an engine gets boosted, piston, crank, cylinder wall or rods, just seems like the rod is the weak link, if you beef up the rod but still keep it short, what's saying that you won't have piston failures?

 

[Studroes144]

Another thing I should add too is after freshening up that engine 3 time on the wheeler I decided to go to a long rod stroker, reworked the engine and head layout so it would all work plus I raised compression a decent amount, 3 years on that setup and it never lost compression. Going shorter in my opinion is not a good idea, especially seeing the engine has tons of compression to begin with then start forcing more air into it, if anything they should've went longer with a lower compression piston to make it work.

 

[Sunvang]

Got it. But he is also doing the crank and pistons. So Sunvang could do the Carillos and go with aftermarket lower compression pistons. Would make sense if in there already and it all fits.

New rod is 2mm shorter then the new one, so the old motor rods and carrillo wont work without the piston. And the new rods are wider where the bearing is, so a old rod on a new crank would make it have 0.9mm sideways play, compared to 0.15mm that is stock. If it works or not i dont know, but it is a risk.


If i had the money, I would do the Carrillo rods also.

 

[Yamadog]

Carrillo don't offer rods for the new motor yet. Talked to them, and they sat they could have them ready in 6-7weeks.

If your going to the old crank they work it is only if you are staying with the new crank.

From looking at these pictures and # u would think the 2016 would be stronger.

It is all about the metallurgy and that is why I went Carrillo on my rebuild but they worked with the 14 crank cause it was the same as the nytro
.

 

[cannondale27]

Maybe we should think of the downstroke. On Phazer the skirt of piston actually sticks out of the bore on downstroke. By using a shorter rod and moving the piston pin down the piston would be up higher in bore on downstroke. Who knows why. But if with the new parts a guy was able to stroke the motor 2mm that would be something! My quad has 2.2mm stroker crank and it is a unreal difference in power.

 

[Yamadog]

A couple of yrs ago I stroked an 07 Apex motor out of a crashed one and stuffed it into my 1st RX that had blown the motor and with a little head work, fuel controller and the stroked crank it went from he stock 155 to about 189 hp.

 

[cannondale27]

You know as bad as this situation is if Yamaha can get the parts right all the commonality of the motor parts will open up alot of possibilities without having to go aftermarket. The UTV is stuck at 1000cc because of some manufacturer agreement but I dont believe one exists for the sleds and the Jet Ski. Anyone ever look into the Jetski Motor?

 

[Tarzan]

So they can just change piston for lower compression is my guess.

Yepp,if Yamaha come with a new model with a factory turbo they just have to change piston to the engine to lower compression. Yamaha will not go with chim like mcx.

 

[shagman]

You know as bad as this situation is if Yamaha can get the parts right all the commonality of the motor parts will open up alot of possibilities without having to go aftermarket. The UTV is stuck at 1000cc because of some manufacturer agreement but I dont believe one exists for the sleds and the Jet Ski. Anyone ever look into the Jetski Motor?

Jet ski motor is just like snowmobile 1049cc.


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[Dpaulo]

Just spoke to my dealer,

I have a late build '16 xtx le

Brand new 0 miles (didn't even get to register it yet)

Would trade it for an early build ltx le
For a grand....

What you guys think? Go for the early build proven motor???