kinda let down today

[Murph]

To be perfectly clear.....I believe there is an algorithm in the ECU that measures rate of acceleration. If the motor gains revs too quickly, it will cut out.

The motor can gain revs too quickly in hero snow, track unloading, and other situations WITHOUT actually hitting the rev limit-- that is why when you open the throttle slowly it won't have a problem, or if you get out of the throttle and then back in it. A motor acceleration algorithm is how we used to do traction control on roadrace motorcycles when wheel speed sensors weren't allowed.

I have run all three of our Stock Pros in 60 degree weather over the last two seasons at 8000' and have not experienced a "barometric" parameter issue.

 

[SNOMAN1174]

Fcr112 it sounds like the same thing. I can't convince myself that it was hitting the rev limiter. A couple times I was barely moving with very very minimal track slippage and the bog was def there. Just like you said after the sled cooled down and more importantly after the sun started hiding some everything went back to normal. I'm really liking temp as the issue.

 

[winter brew]

I can see the temps being the issue at that high of altitude....didn't realize you were that high....combined with warm temps it very well could be out of the compensation range and just running rich.

 

[SNOMAN1174]

Yes winterbrew. I'm really high when I ride........the elevation is to.

 

[IceCap]

I have been trying to fix a WOT bog for some time now.... mine only does it after a longer pull of 20-30 seconds. I have been thinking that it is a temp problem.

Not sure if it is the pipe building to much heat or the intake temp is to high because of under the hood temps are to high??
I really hope someone will figure these sleds out..... The dealers don't know much.... I think Polaris knows about this and what is causing the bog ..... they are not willing to address this issue.

 

[FCR112]

My issue started after the sled and the temps cooled down significantly. I also have a Pro rather than an Assault, so take that into consideration about my track comments on the hardpack.
In my case the track was definitely spinning when it happenend. I think Murph is onto something.

 

[Super Sled]

To be perfectly clear.....I believe there is an algorithm in the ECU that measures rate of acceleration. If the motor gains revs too quickly, it will cut out.

I've experienced this too this spring riding on a 55 degree day on crusty snow at wfot and I think Murph is 100% right here.

The question then is, why would Polaris add that code into the ecu.......

 

[Joe57]

Just to be clear, we AK riders rarely get above 6,000 feet. Yes, the mountains are big and impressive....but they be at sea level, mang.

Turnagain Pass, the bowls above the Placer River, Lost Lake....all beyond fantastic mountain riding destinations are for the most part below 4,000 ft.

You boys in the Rockies ride much higher elevations then we do.

Sure, Mt McKinley is 20,000+ but you can't ride there (legally).

Hell when I leave the house I'm a little over 7000 ft and we ride above 11000 on some days............ my sled did the same thing when riding around 50 degrees

 

[Reg2view]

I've experienced this too this spring riding on a 55 degree day on crusty snow at wfot and I think Murph is 100% right here.

The question then is, why would Polaris add that code into the ecu.......

Avoid overrev and warranty claim, tossing crank out of phase, e.g., blown belt, trackstand hero, primary spin, gearing fu, maybe.

 

[SNOMAN1174]

So I am now convinced the problem was temp related. Same sled, same riding spot, only dif was temp was much cooler today. No problems at all. In the morning when we unloaded at 9am the sled ran awesome. Pulled 8k rpm and no bog at all. At the peak of the day the temp got into the upper 40s. Sled did not bog but was a bit more doggy. Talking to the people who were with me last week when the bog occurred I guess it was closer to 60 or 65 degrees last time out. If the ecm does not properly compensate over say 60 degrees this would explain the bog. Today being colder and all other conditions the same had no bog. I have no way to prove my theory other than getting a ecm spec confirmation from polaris so I guess it will remain a theory but today pretty much convinced me. There is probably another 2 or 3 weeks left so I'm gonna test my theory this week. Weather supposed to warm back up so I will see if bog returns. My guess is it will.

 

[FCR112]

Mine ran perfect all day today. 35 miles of crusty azz, slippery, spring/summer snow. Crunk! (not sure if I made that up but it means crusty junk) ... I'm still going with Murph's theory on what I experienced last time out. Waited until about 2pm to start. Temp was 55, ended at 39 degrees 5 hours later. Elev 11000 and up. Good day!