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I am noticing this on BOTH the 2020 850's were running and it's not something in the last 6 we have owned which has come up. I'm thinking the maps have changed but it could also be the muffler temp sensor.

I've really picked up on this while doing clutch work and wanted to get it out there and a discussion started and hopefully others can chime in with their own personal experience.

I'm finding the pipes on the 20's have to be hot to perform and there is very little grace period. If lots of 20's are like ours I would tell guys now plan to loose a lot of drag races to 17-19's

If your out on a 20 running it no problem rpm is spot on as long as it's cruising 40 mph or better but slow it down for even 30 seconds and punch it and rpm is low. 7400-7600 on my clutched one and slightly better 7500-7700 on the stock one. Now run it hard for 30 seconds and slow down and hit it bang 7900-8000.

Stop for say 30 seconds to line up and race and the pipe cools off and RPM is down. Not sure if bumping 2* timing will help but that's the road I'm headed towards.
 

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Have not noticed this at all on my 2020. Always bang on 7900-8000 RPM. Same as my 18 850 was.

I would suggest ...back to stock clutching and ditch the XS-821 belt. Good Luck.
 

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I am noticing this on BOTH the 2020 850's were running and it's not something in the last 6 we have owned which has come up. I'm thinking the maps have changed but it could also be the muffler temp sensor.

I've really picked up on this while doing clutch work and wanted to get it out there and a discussion started and hopefully others can chime in with their own personal experience.

I'm finding the pipes on the 20's have to be hot to perform and there is very little grace period. If lots of 20's are like ours I would tell guys now plan to loose a lot of drag races to 17-19's

If your out on a 20 running it no problem rpm is spot on as long as it's cruising 40 mph or better but slow it down for even 30 seconds and punch it and rpm is low. 7400-7600 on my clutched one and slightly better 7500-7700 on the stock one. Now run it hard for 30 seconds and slow down and hit it bang 7900-8000.

Stop for say 30 seconds to line up and race and the pipe cools off and RPM is down. Not sure if bumping 2* timing will help but that's the road I'm headed towards.
If you're using the 821 belt that's the problem
 

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If these have can sensors, the 19 and 20 are very sensitive to cans. The stock can makes the most hp on a stock can when its hot.

Sent from my iPhone using Tapatalk
 

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Is the sled still in break in mode? That type of pipe temp and rpm issue is almost always related to a fuel rich scenario. If it’s still in break in mode, I wouldn’t be too concerned yet.
 

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Discussion Starter · #6 ·
Have not noticed this at all on my 2020. Always bang on 7900-8000 RPM. Same as my 18 850 was.

I would suggest ...back to stock clutching and ditch the XS-821 belt. Good Luck.
Belt and clutching is irrelevant as the stock one meaning out of the box stock does the exact same thing. Been using the xs belt for 3 seasons never ever had this.

I'm leaning towards map change or temp sensor. No cans on the sleds what so ever.

Brent you have a free ride no? If so they run the center body temp sensor which sharpens them up a lot.

This is something I have not done to my 20 yet but have in the past.
 

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Discussion Starter · #7 ·
Is the sled still in break in mode? That type of pipe temp and rpm issue is almost always related to a fuel rich scenario. If it's still in break in mode, I wouldn't be too concerned yet.
1,000 miles on one 840 miles on the other. Break in is long done.
 

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Belt and clutching is irrelevant as the stock one meaning out of the box stock does the exact same thing. Been using the xs belt for 3 seasons never ever had this.

I'm leaning towards map change or temp sensor. No cans on the sleds what so ever.

Brent you have a free ride no? If so they run the center body temp sensor which sharpens them up a lot.

This is something I have not done to my 20 yet but have in the past.
Yuppers. My summit had the center probe as well.

These big paddle track sleds can be difficult to clutch. Have to clutch for hot hot heat soaked motor. Then expect a little over rev on cold days. There is a ton of load on the drive system vs the shallow tracks with nails in it.

Big highway gears can be a culprit as well. tough to recover to rpm with big track at speeds.
 

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What outside temp are when this is happening? I know all my skidoos never ran right in anything over 25f, and my 2019 850 is super slow in warmer temp
 

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Belt and clutching is irrelevant as the stock one meaning out of the box stock does the exact same thing. Been using the xs belt for 3 seasons never ever had this.

I'm leaning towards map change or temp sensor. No cans on the sleds what so ever.

Brent you have a free ride no? If so they run the center body temp sensor which sharpens them up a lot.

This is something I have not done to my 20 yet but have in the past.
Could you explain how you used them before.
Interesting situation on low rpm with a cold pipe. Not what I would expect, could be a program change to help with cold seizures or wear to the piston during swelling period. Just trying to put some logic behind what your seeing. Just a guess so far.
 

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Interesting. If the sled has 1k miles on it and 840 on the other one, it's definitely not a break in issue.

I know you've been a huge proponent of the XS 821 belts...so I'm sure that's not the issue...especially if the stock clutching and belt setup did the same thing.

Meat head...A cold pipe doesn't mean that the engine is cold...and I'm sure when he says "cold pipe" he's really just saying any time the pipe isn't hot.

I would consider a hot pipe anything over 800 - 850 degrees.

You can have a sled with a coolant temp of 130 degrees, but a pipe temp of only 600 degrees. This would happen if you were putting around at low/medium speeds in crappy snow conditions. In this scenario, the piston and cylinders would be dimensionally stabilized. Yes, a long WOT pull would heat up the top of the piston considerably, but that's not what we're talking about here, because the pipe would be hot at that point too.
 

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Interesting. If the sled has 1k miles on it and 840 on the other one, it's definitely not a break in issue.

I know you've been a huge proponent of the XS 821 belts...so I'm sure that's not the issue...especially if the stock clutching and belt setup did the same thing.

Meat head...A cold pipe doesn't mean that the engine is cold...and I'm sure when he says "cold pipe" he's really just saying any time the pipe isn't hot.

I would consider a hot pipe anything over 800 - 850 degrees.

You can have a sled with a coolant temp of 130 degrees, but a pipe temp of only 600 degrees. This would happen if you were putting around at low/medium speeds in crappy snow conditions. In this scenario, the piston and cylinders would be dimensionally stabilized. Yes, a long WOT pull would heat up the top of the piston considerably, but that's not what we're talking about here, because the pipe would be hot at that point too.
Your kidding me.. never would have guessed that about a cold pipe. Stop and think about it. Most of the time after sitting taking a break talking about a race. What happens next after a 1/2 hour??? Go figure a race breaks out. I see it all the time. Long cool down followed by wot for a half mile. Think the pistons wont swell fast than the cylinders? Society is fixing everything for the stupid ones. Do you think brp is not protecting a 6k power plant?
I get your point but agree with it looking at a larger perspective. The low rpm is likely controlled by the rave valves to do its job for some sort of reason in the logic.
 

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Any way to activate pipe temp on your gauge so you can confirm? I had it done on my 17 and 19, actually muffler temp.
 

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Discussion Starter · #14 ·
Any way to activate pipe temp on your gauge so you can confirm? I had it done on my 17 and 19, actually muffler temp.
We're going to be exploring that avenue as well but it's looking a lot like pipe temperature / muffler temperature are dictating performance. I'm leaning towards the pipe needing to be hot to make power this leads me to believe timing has been pulled from the 20's possibly??? Less heat in the pipe down low maybe I don't know but if we add say 2* and this solves it we should have an answer.

You really wouldn't notice this unless you stop to drag race and it takes a few moments to line up or say moving pivot weights around and it's down instantly.

For example my sled is over revving stop and add 2-4 g pivot (example) and it won't pull 7400. Get pipe hot again and it's still wanting to pull 8000-8100. Cool down to line up and take off 7400 :( get it hot again riding around 8000-8100.

That's just an example of how they both behave given the time frame. The stock one has had zero adjustments and does the exact same thing. I'm being lead to believe pipe temp is critical. We'll see as time goes on but I'm putting it out there now to discuss.
 

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So Polaris has a comparable 850 since last year. and they even gained a few hp with a better tune in the 2020s. And now brp is making the 2020 slower/neutering them?

That sounds crazy
 

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ive always found that with my 19' if cruising say 40mph or faster at a steady rpm, hit it WOT and has a hard time revving past 7600rpm. but if doing the same thing cruising at 40mph steady rpm and let off throttle slowing to 30mph and nail it wide open it will hit 8000 or higher. its probably more clutching in my case.

You really wouldn't notice this unless you stop to drag race and it takes a few moments to line up or say moving pivot weights around and it's down instantly.

For example my sled is over revving stop and add 2-4 g pivot (example) and it won't pull 7400. Get pipe hot again and it's still wanting to pull 8000-8100. Cool down to line up and take off 7400 :( get it hot again riding around 8000-8100.
you are definitly onto something with these results^^ have you tried a similar test with your 18' since noticing on the 20's??
 

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ive always found that with my 19' if cruising say 40mph or faster at a steady rpm, hit it WOT and has a hard time revving past 7600rpm. but if doing the same thing cruising at 40mph steady rpm and let off throttle slowing to 30mph and nail it wide open it will hit 8000 or higher. its probably more clutching in my case.

you are definitly onto something with these results^^ have you tried a similar test with your 18' since noticing on the 20's??
clutching
 

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We're going to be exploring that avenue as well but it's looking a lot like pipe temperature / muffler temperature are dictating performance. I'm leaning towards the pipe needing to be hot to make power this leads me to believe timing has been pulled from the 20's possibly??? Less heat in the pipe down low maybe I don't know but if we add say 2* and this solves it we should have an answer.

You really wouldn't notice this unless you stop to drag race and it takes a few moments to line up or say moving pivot weights around and it's down instantly.

For example my sled is over revving stop and add 2-4 g pivot (example) and it won't pull 7400. Get pipe hot again and it's still wanting to pull 8000-8100. Cool down to line up and take off 7400 :( get it hot again riding around 8000-8100.

That's just an example of how they both behave given the time frame. The stock one has had zero adjustments and does the exact same thing. I'm being lead to believe pipe temp is critical. We'll see as time goes on but I'm putting it out there now to discuss.
Regardless of it happening on the stocker, I do not think you can ignore some of Ski-B's thoughts. With the ramps you are using and conditions you may be overloading low to mid so that if the engine is down just fraction it hold it back. With those dalton ramps try clicker 4 with a little more weight, less start on the helix or more start on the secondary spring, nothing new to you of course.
 
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Discussion Starter · #19 ·
Regardless of it happening on the stocker, I do not think you can ignore some of Ski-B's thoughts. With the ramps you are using and conditions you may be overloading low to mid so that if the engine is down just fraction it hold it back. With those dalton ramps try clicker 4 with a little more weight, less start on the helix or more start on the secondary spring, nothing new to you of course.
I have some ideas for sure on what's going on and I am more or less tossing the scenerio out there to others who may find themselves having troubles. It's taken me a bit to keep figuring things out as I go and want to help others get onto it quicker. Something for guys to watch for. I know I will have a solution to it no doubt. As I sit I have made considerable gains in the 2020 which I am excited about.
 

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Power valves have long governed the peak rpm on skidoo's.
My 18 cuts its nuts on a hot pipe. Yesterday was a prime example. Set the cruz at 7100 rpm on the grade, around 90 ish. Every slow down or stop yielded low return rpm at 7400 nearly every time. It's so predictable its sickening.
So basically this is a good tool for some, learn how and when to line your sled up against another. Great thread to inform new 850 owners so they don't look like a clown on race day. My 18 likes a cool ish pipe at the line. Hot it lays down.
Keep up the fight. Likely impossible to fix it.
 
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