What's thoughts on the axys 850

[cdnredneck_t3]

From what Eric Woog said on Facebook they left the bore the same and lengthened the stroke. Should increase the bottom end torque I would think.

 

[skegpro]

Dynotech measures a broke-in Cat 800 at 155 HP. Same as the Poo.

Really shows how consistent dynotech is if that's the case.

Here they have the cat 800 dynoed at over 160HP.

So either they are lying or you are.

But don't take it personal my 800 etec used to be over 160hp then magically the 850 came out and it was only 150ish HP.

Go figure.

 

[skegpro]

From what Eric Woog said on Facebook they left the bore the same and lengthened the stroke. Should increase the bottom end torque I would think.

4 mm longer stroke

 

[JMCX]

Really shows how consistent dynotech is if that's the case.

Here they have the cat 800 dynoed at over 160HP.

So either they are lying or you are.

But don't take it personal my 800 etec used to be over 160hp then magically the 850 came out and it was only 150ish HP.

Go figure. //uploads.tapatalk-cdn.com/20180307/2eafab977562efdc6cd105d267094cf7.jpg

I looked again and sorry l was wrong. The production Ctec 800s dyno at 151 HP! The only 'stock' one that hit 160 was a preproduction unit that obviously had some engineering tweeks. Dynotech used a PCV to tweek a production unit up to 155HP.

All of this is well laid out by Jim if you have a subscription.

 

[dragonweld28]

i subscribe to dynotech and feel they are the most reliable testing facility out there.
Cat - 151
Axys - 153
Doo 850 - 168.
New polaris 850.... 153 x 1.09 = 167.

Im sure that they will get there hands on one soon and will have real numbers for everyone.

 

[skegpro]

i subscribe to dynotech and feel they are the most reliable testing facility out there.
Cat - 151
Axys - 153
Doo 850 - 168.
New polaris 850.... 153 x 1.09 = 167.

Im sure that they will get there hands on one soon and will have real numbers for everyone.

What model of cat engine are you talking?

So confused, some of dynotechs charts for the ctech2 say 160 hp.

Can you clarify which are not 160hp?

 

[dragonweld28]

they were able to achieve 160 with a PC5. They added fuel and timing. All the other 2018 Ctec 800 motors dyno'd at 151-152 hp

 

[takethebounce]

You always have to look at dynotechs reports closely. Remember they were the ones who achieved 163hp on the 800 etec. That was once with a hot tune and timing advanced. Then Doo took that number and used it for marketing.

Much of the time dynotechs numbers are posted after running pipes or other mods. The only way to closely compare is run them all stock on the same day only after break in is complete. Even then two of the same sleds can have slightly different numbers.

As far as the ‘19 850. I would like one but I can wait. Mine still has warranty until Dec 2019.

 

[skegpro]

they were able to achieve 160 with a PC5. They added fuel and timing. All the other 2018 Ctec 800 motors dyno'd at 151-152 hp

If you got a curve for the stock one can you post all I can find is this curve and they didn't say anything about the PC5 being used......

 

[JMCX]

If you got a curve for the stock one can you post all I can find is this curve and they didn't say anything about the PC5 being used......


//uploads.tapatalk-cdn.com/20180308/6a58dda96cdd6605e68f26c2335e21f4.jpg

Do you see the date at the bottom left of the graph? That is the ringer preproduction 800 Ctec. The production ones seem to be all in the 151 range. Add timing and fuel tweeks 155hp. Add pipe and timing, fuel get 160ish. In one write-up Jim speculates what Cat may have done after testing a modified factory pipe that, with timing and fuel tweeks, is almost identical to the preproduction unit. It is not fair to Dynotech to post what is supposed to be subscriber information. I have been following Dynotech for 25+ years. Jim goes to great lengths to be accurate and clear on what is going on.

Cat obviously has the chassis dialed.

 

[skegpro]

Do you see the date at the bottom left of the graph? That is the ringer preproduction 800 Ctec. The production ones seem to be all in the 151 range. Add timing and fuel tweeks 155hp. Add pipe and timing, fuel get 160ish. In one write-up Jim speculates what Cat may have done after testing a modified factory pipe that, with timing and fuel tweeks, is almost identical to the preproduction unit. It is not fair to Dynotech to post what is supposed to be subscriber information. I have been following Dynotech for 25+ years. Jim goes to great lengths to be accurate and clear on what is going on.

Cat obviously has the chassis dialed.

We'll wtf, that's worse than what VW did in my mind.

I want my 10HP back.

 

[takethebounce]

We'll wtf, that's worse than what VW did in my mind.

I want my 10HP back.

It’s okay. Doo guys thought for 5 years the Etec made 163 hp yet wondered why a 145hp Pro out rode them. To this day most of them are still scratching their heads.

 

[LUCKY 7]

That is so true. A DOO buddy of mine always let me know that his 163hp sled had way more HP than my pro. He's passed on now and I wonder if he ever realized he was wrong.

It’s okay. Doo guys thought for 5 years the Etec made 163 hp yet wondered why a 145hp Pro out rode them. To this day most of them are still scratching their heads.

 

[Eldereldo]

We'll wtf, that's worse than what VW did in my mind.

I want my 10HP back.

Might be able to, guess there is a new ECU program on the 2019 that’s is more aggressive, should be able to get the 2018 updated and get some of that lost power back.

But I am curious about the compared results. Do they do multiple runs over several months to account for variations in atmospheric conditions caused by high or low pressure systems? Or do they somehow supply air to the motor at a standard pressure, temperature and humidity to control all that.

 

[52weekbreak]

Given challenges with new releases it will be interesting to see if Polaris gets it right on the first go. Always nice to see new stuff coming out.

 

[52weekbreak]

4 mm longer stroke

I've been told that while the length of the stroke is helpful, there is no substitute for volume.

 

[Lund]

To me it will be interesting to see how long these 850 hold out. It is in my opinion and observation from past experience that they might not live as long if they are tuned to run as fast as the 800, 8,000+rpm.
Generally a longer stroked motor don't like to turn as fast, harmonics have always been a big issue with them but i understand the attraction to them as they will produce a better torque curve.
Sled motor have always fared better in a square configuration for performance longevity.
About 15 years ago a buddy of mine converted a water craft motor to a sled for that very reason. Longer stroke makes better torque, well the intent was good, it just couldn't take long term high rpms needed to run the clutches properly. Water craft motors are longer stroke then sled motors but also run at a lower RPM.
Of course these are not water craft motors but specifically sled motors but the principle still applies. Long stroke motors don't like high RPM's for too long.
I'm thinking they won't live long or as long as an 800.
JMO and food for thought.

 

[CUSO]

Well the 850 engineers apparently have been doing homework:

Stronger, re-engineered cranks, Both sleds have had improvements there.

Bearings are more heavy duty, more homework.

Better lubrication of bearings. A Plus.

Updated pistons... and con rod bearings... Another plus..

Sorry to rain on your parade Lund, but I think larger stroke 2 strokes are here to rule the technical aspect of mountain sledding..

To me it will be interesting to see how long these 850 hold out. It is in my opinion and observation from past experience that they might not live as long if they are tuned to run as fast as the 800, 8,000+rpm.
Generally a longer stroked motor don't like to turn as fast, harmonics have always been a big issue with them but i understand the attraction to them as they will produce a better torque curve.
Sled motor have always fared better in a square configuration for performance longevity.
About 15 years ago a buddy of mine converted a water craft motor to a sled for that very reason. Longer stroke makes better torque, well the intent was good, it just couldn't take long term high rpms needed to run the clutches properly. Water craft motors are longer stroke then sled motors but also run at a lower RPM.
Of course these are not water craft motors but specifically sled motors but the principle still applies. Long stroke motors don't like high RPM's for too long.
I'm thinking they won't live long or as long as an 800.
JMO and food for thought.

 

[Lund]

Well the 850 engineers apparently have been doing homework:

Stronger, re-engineered cranks, Both sleds have had improvements there.

Bearings are more heavy duty, more homework.

Better lubrication of bearings. A Plus.

Updated pistons... and con rod bearings... Another plus..

Sorry to rain on your parade Lund, but I think larger stroke 2 strokes are here to rule the technical aspect of mountain sledding..

I wasn't trying to spin a negative thought about it, it was just a thought.
As for the engineer comment and doing their home work. It doesn't sound like you've been around long because it wasn't that long ago...LOL... certain engineers said the same about a few big motors that were in production a few years ago. Big this Big that, lots of testing, several years of R&D and the funny thing, they turned out to be bombs.
Funny part, both these bombs were from the builders of these super duper 850's.
But just like the past, lots will be sold...hopefully your right and they truly did their home work or DEJAVU

 

[LennyR]

But was part of the problem the initiative to keep them as light as possible ? Can not the harmonics issue be compensated for with balancers , plus beefier components. And if so , is the additional weight justified by the hoped for performance increase ?