Dalton QAY70, TB 270, need your help

[uofm]

Stock springs. This is what I have on a 2018 Sidewinder with an 1.75 back country track with a stock can. This morning 11 degrees, flat hard pack trail. Pin it runs right up to 8950 rpms, pulls like a freight train. Smile from ear to ear.
An hour or two later snow is lose, warmer by 5 or 10 degrees. Sled will not pull 8000 rpms. Not smiling from ear to ear. 3rd day in a row it does this. I can barely out run a vector (disappointment) to say the least. This has to be in the clutching (springs) is what I can figure. Any help with you experts out there? Help me finish the season smiling again please.

 

[jonlafon1]

That’s a huge drop in rpm. Check both springs. Deep lug track and heavy sugar snow will drop you for sure but 950 rpm? Seems a lot. To heavy on the clutch weights?

 

[SaskAttack]

Agree with jonlafon, replace springs. They can and do take a set after a while and cheapest "fix" so worth a try. front first.

 

[Crossfire12]

Heavier secondary spring, you have 270hp, on ice no resistance

 

[Motorhead]

Stock springs. This is what I have on a 2018 Sidewinder with an 1.75 back country track with a stock can. This morning 11 degrees, flat hard pack trail. Pin it runs right up to 8950 rpms, pulls like a freight train. Smile from ear to ear.
An hour or two later snow is lose, warmer by 5 or 10 degrees. Sled will not pull 8000 rpms. Not smiling from ear to ear. 3rd day in a row it does this. I can barely out run a vector (disappointment) to say the least. This has to be in the clutching (springs) is what I can figure. Any help with you experts out there? Help me finish the season smiling again please.

Sounds like a boost leak which occurs once all warms up?
I also run both stock springs on my TD 260-270 tune but with a 1.25” track. Mine may fluctuate 100 rpms dependent on ambient temp and snow conditions, but 850 like you state does not equate to clutch set up for me.

You state 270TD tune with QAY 70. So it is the Max Spool 16?
2 bar or 3 bar?
Stock BOV or aftermarket.
What kind of boost readings when it is running good and when it’s not?

Why do you think it’s clutching? 850 rpm loss is a lot!

 

[uofm]

Sounds like a boost leak which occurs once all warms up?
I also run both stock springs on my TD 260-270 tune but with a 1.25” track. Mine may fluctuate 100 rpms dependent on ambient temp and snow conditions, but 850 like you state does not equate to clutch set up for me.

You state 270TD tune with QAY 70. So it is the Max Spool 16?
2 bar or 3 bar?
Stock BOV or aftermarket.
What kind of boost readings when it is running good and when it’s not?

Why do you think it’s clutching? 850 rpm loss is a lot!

There is just no rhyme or reason behind it. The rpms slowly drop off over a few hours or less of time. I figured the stock spring's were to weak and after running a bit lose there tension or strength. I have no way to test for a boost leak. Can the dealer do that because I had it to them and they said the inter cooler vent was froze shut. They let it thaw out for 2 days, took it out and they said it ran fine. I took it this weekend and it did not run over 8100 rpms when I took it out in the snow. But first thing in the morning super cold on super frozen trail it pulled 8950 and ran like it should. Drove it for a half hour. Went in for breakfast and ate probably an hour and a half later went back out and the trails were loosened up from a quick warm up and a bunch of sleds tearing them up it dropped down to about 8300 rpms. I am at a loss. I do not know much about turbos but I know something is wrong. I was going to start with the clutching. I was sceptical also with that much drop because a 270 hp sled should wind them clutches right up.
Where do you reccomend I start? If it is a boost leak where do I go from there. I checked all the clamps. They are tight. The sled has 1900 miles on it.

 

[maim]

have you checked it for peak rpm after you have been running it for awhile, 10+ min? sitting even when off will heat soak a sled and until it has been moving for a bit and cooler air has worked its way through.

 

[KnappAttack]

Knowing that information from the dealer, I'd be installing a aftermarket blowoff valve. It could be leaking open and/or sticking open perhaps. It should not be dropping 600-650 RPM from clutching unless you are way off to start with.

Is the intercooler plugged with ice and not cooling the intake charge? What are your intake temps when this happens? It's got to be dropping power from hot intake temps or a stuck open blowoff valve.

Got any turbo buddies that know anything there you are riding with?

 

[Motorhead]

There is just no rhyme or reason behind it. The rpms slowly drop off over a few hours or less of time. I figured the stock spring's were to weak and after running a bit lose there tension or strength. I have no way to test for a boost leak. Can the dealer do that because I had it to them and they said the inter cooler vent was froze shut. They let it thaw out for 2 days, took it out and they said it ran fine. I took it this weekend and it did not run over 8100 rpms when I took it out in the snow. But first thing in the morning super cold on super frozen trail it pulled 8950 and ran like it should. Drove it for a half hour. Went in for breakfast and ate probably an hour and a half later went back out and the trails were loosened up from a quick warm up and a bunch of sleds tearing them up it dropped down to about 8300 rpms. I am at a loss. I do not know much about turbos but I know something is wrong. I was going to start with the clutching. I was sceptical also with that much drop because a 270 hp sled should wind them clutches right up.
Where do you reccomend I start? If it is a boost leak where do I go from there. I checked all the clamps. They are tight. The sled has 1900 miles on it.

Your 270 TD tune should show the boost level on your gauge if you scroll through and simply leave it on hours.

Check what you have for boost during the smile time, and during the frown time. That May help in choosing what might be your next step. What a TD tune are you using?

 

[uofm]

Your 270 TD tune should show the boost level on your gauge if you scroll through and simply leave it on hours.

Check what you have for boost during the smile time, and during the frown time. That May help in choosing what might be your next step. What a TD tune are you using?

In lies a problem. The left side of my gauges quit working. Story of my life.

 

[ClutchMaster]

That’s a big difference that goes away for a clutch issue. Sounds more like power loss to me, even at 8000 rpm you should still have 200 hp kicking a vectors a$$.

 

[Motorhead]

In lies a problem. The left side of my gauges quit working. Story of my life.

My hour gauge is on the right side cluster on my 17 Winder.

Would be nice to have someone with a bit of knowledge with theses Winders take a peak at it.

Cracked tubes, cracked exhaust, BOV, turbo problems, and more could drop your boost numbers.

Too many other things that it could be. Fuel problems are a whole other line of thought, that’s why it would be nice to rule out boost problem. Clutching probs?? Again not my guess, but that is just a guess.

Others answering your questions are much more capable then this backyard DIY tech. So hope you find your problem sooner then later.

 

[sxr70001]

Martin Powersports in Cadillac is a TD dealer, they might be able to help you.

 

[uofm]

Martin Powersports in Cadillac is a TD dealer, they might be able to help you.

I work in Cadillac. And I have never heard of them. Priceless in Gaylord did my programming. I was going to call them and try to get it up there but Saturday is the only day I can take it. Would you recommend Martin Powersports? Will they check the sled out or do they just program?

 

[sxr70001]

They are pretty good guys and seem pretty knowledgeable. They will be able to check things over.