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850 Khaos always takes a few pulls to start?

J

Jaynelson

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Nov 26, 2007
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Some do, some don't. If your's is taking 3-4 pulls to start, I bet holding just a little throttle will get it down to 1-2 pulls when warm.

Cold I would recommend a couple/few pulls with no throttle, and then use it if needed.

If it runs good otherwise, there's no real fix. Electric start kit maybe.
 

Matthew runge

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2021 khaos 850
800 miles
Ves extreme oil

This sled always takes 3-5 pulls to start. It doesn’t matter if it has old or new plugs, has been sitting 15 minutes or 15 days or months.

I’ve seen other posts of many people having the same issue, but I haven’t seen any posts of what the “fix” is. Has anyone diagnosed this on their sleds? Thanks
Change to cobra pull cord and it will start right up. The factory pull cord stretches too much and loses that pop
 

BeartoothBaron

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Sounds kind of similar to my Pro 800. On warm starts, I've learned to always give it a full commit pull: that usually starts it with one pull. A tepid or off-axis pull won't do it unless you just turned it off. If you don't get it in the first couple pulls, it won't start unless you hold the flipper open (I think it floods out). Cold starts are worse for me though. Could take a dozen or more pulls. Doesn't seem to flood out cold; maybe it just takes that much time to get things charged up enough to fire the injectors. You're pretty well warmed up by the time it's running, anyway...

Meanwhile, I hop on a Doo 850, and it's like starting my old 600 by comparison. It's not something that I'd think of switching brands over, but would be a big plus if they could nail it down. I don't need e-start, but Polaris does a good job of making it more of an upgrade than it should be.
 

Teth-Air

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I have had 2 850's and both started after 2 pulls cold and just 1 flick of the wrist when warm. My buddies would flood easy though. Something is not equal in the calibration with these sleds. Not likley the TPS anymore but it could be fuel pump or exhaust temperature sensor or map sensor etc. I wonder if aftermarket cans are resulting in different sensor temperatures? Hotter spark plugs seem to help.
 

BeartoothBaron

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Yeah, come to think of it, I have pulled the rope on an 850 (Poo) that was easier to start than my Pro. Sounds like some aren't bad, some are finicky. And how will you even know until after you've bought one? I've never bought a sled in a time and place where you could test out the cold start, and even a warm start might be different if it's 80 degrees vs typical riding temps.
 
A
Nov 26, 2007
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After the latest update my 850 has really gone haywire, several pulls to start, and it now has a start and stop surge around 4,200 rpms. If you are trying to simp[y putter around a parking lot for instance "just above engagement" the sled won't run, it surges as if someone is pulling the kill switch up and down. I asked the dealer if I could back to the prior map and was told they could not do that. It appears every mapping update they have installed creates more glitches and problems than the prior version. I wonder if they have anyone in the country on the snow that gives them a test run prior to leaving Roseau.
 

TRS

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they may have an issue in their shop that is causing the ECU flash to miss data.
Steel buildings and fluorescent lighting do cause problems.
 

MARV1

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Adjust the throttle tighter! My 2019 SKS has electric start but I’ve used the recoil many times just to feel the cranking compression! 10 added lbs of electric start is worth it, comes standard on 4/5 of skidoos.
 

Wheel House Motorsports

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It’s a 19-21 850 fuel injection system weakness.

Happens on every one I have ever seen or ridden. (A serious pull on the rope with a crack of the throttle does make for one pull starts warm most of the time)

The 18-21 800 seems to start easier than the 850’s.
exact same experience.

tiny touch of the throttle and a real pull usually gets it to 1 pull when warm. otherwise 3+ when its cold is just how it is and how they've been.

22+ with the additional flywheel pickups seems to have helped a bit, much more consistent 2-3 when cold and 1 when warm.
 
A
Nov 26, 2007
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For those having stalling issues when trying to go into reverse, give your belt deflection a look. If you run an extremely tight belt, (as in one that turns the track when you pick up the rear of the sled or squeals) you might want to loosen it up a bit. The belt will create just enough drag on the crank that reverse spin won't happen, just kills it. I've run into several misinformed snowmobilers over the years that think when they put on a new belt that the squealing is normal for a while. Yikes!!!!
 
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Winshady

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Only thing I can say is, you gotta rip that cord. By the end of the day I can barely start my 850. Because I’m tired. Maybe give it 2or 3 pull throughs then one good hard yank. I’ve ordered an electric start sled but not sure if the weight penalty is gonna be worth it.
 
C
Jan 14, 2020
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Unplug your whole key switch from the harness. My 850 starts 1st pull nearly ever time now and isn't a weak start.

Kinda stupid but the key switch is blocking power or something
 

Snowman10

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Change to an aftermarket throttle block that eliminates the TPS plunger or purchase a bypass that also eliminates the TPS.
Chris Perkins at 208-794-8673 makes the bypass for 2011-2023 sleds and sells them for $25 vs $40+ from others. I purchased three of them, added one to my sled and the problem was solved. I then gave the other two to some buddies of mine, so that they would have one in their group of riders in case it happens to one of them.
You should carry one of these bypass plugs that clips right into the wiring harness for safety reasons as well. In February my TPS plunger all of a sudden went out 9 miles from the truck. When this happens or if you break a throttle by hitting a tree, the sled will start, but it will not engage the primary clutch and you are stranded. You cannot splice the wires together (I tried that), because there has to be a resistor installed as well.
Luckily for me a Polaris Dynamix Rzr with a new set of tracks pulled up and drug me back to the trailer, which was way better than putting a strain on a buddys sled and or belt. The owner of the Rzr couldn't even tell that I was back there.

The bottom line is that every group of riders should have one of the bypass units with them when riding, just in case they have problems with one of their sleds.
 
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S
Apr 30, 2011
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When I bought my 2021 Khaos 850 it would start every time on 2 pulls. Reverse worked flawlessly. 2nd year it had an issue dyeing when I put it in reverse 3 out of 4 times. Dealer noticed it when I took it in for the fuel pump recall. He asked if it was happening all the time. Said to bring it in if it doesn't get better. I should have just left it with him. It was still under warranty then. Later in the second year it started to take 3 or 4 pulls to start. Then this year it just stopped working all together. I could run it up the trail from the trailhead for maybe 10 minutes and the sled would die. It would start up again but only go another 5-10 minutes before dyeing again.

Pulled the top end off (my warranty expired...I did not buy the extended) and found the cylinder on the PTO side had a cold sieze. Piston had a hole in it. So I put cylinder juggs, new pistons and rings, new wrist pins. It starts on second pull now and the reverse is working flawlessly again. And has more power than it had when it was new. Maiden voyage was last weekend (5/20/2023)...got 3.5 hours with 2 hours above 3500 rpm.

I used a Indy Specialities top end. He beefs up the bottom of the cylinder to better support the skirt. Looks to be a better design than factory. Hope to report in a few years on how it holds up.

Those having starting issues should start by checking compression on both cylinders. If you have compression issues you will not get the power needed to flick it into reverse. If compression checks out OK, are the plugs fouled? I had an issue with one plug fouling after 2 hours ride...every time. With the new top end the plugs look perfect after 3.5 hour ride.

I hear a lot of people using the Throttle Safety Switch ByPass to fix the issue with sled dyeing. I bought one and turned out to not be the problem. The problem I was having was grabbing throttle the wrong way. I twisted the throttle block a little so that my thumb pad is pushing on the throttle and now it works as it should. Keep in mind, if you use the by-pass you no longer have the protection for a frozen or sticky throttle cable. I saw one video of a guy who got caught up in his track tunnel when the sled rolled over on top of him. A TSS would have saved his jacket and the skin on his back. If installed correctly the TSS should work and not require a by-pass.
 
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