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Discussion Starter #1
I have a 2013 switchback 800 pro r. Pulled out valves to clean, found one valve oily like I have always seen them. The right one was dry chalky brown but was oily under the bellow. Do I have a problem here. Thanks
 

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My guess would be that the right side is getting a bit more heat than the left side because of the pipe. The cooler side condenses more oil on the valve guillotine than the hotter side. I have not noticed that on my 800 SKS, both my valves are about the same when I pulled them to clean them.

If it were carbed, you may be able to adjust jetting on the hot side to add a bit more fuel to cool things down, but with EFI.. .no chance to do that. The oil under the diaphragm would indicate both sides are getting adequate oil, as the oil under there is coming from the exhaust gas that condenses on the undersides of the bellows.

Welcome to the forum!
 

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Discussion Starter #3
My guess would be that the right side is getting a bit more heat than the left side because of the pipe. The cooler side condenses more oil on the valve guillotine than the hotter side. I have not noticed that on my 800 SKS, both my valves are about the same when I pulled them to clean them.

If it were carbed, you may be able to adjust jetting on the hot side to add a bit more fuel to cool things down, but with EFI.. .no chance to do that. The oil under the diaphragm would indicate both sides are getting adequate oil, as the oil under there is coming from the exhaust gas that condenses on the undersides of the bellows.

Welcome to the forum!
Thank you, and thanks for the info.
 

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If the problem was on the PTO side, I would suggest checking that side crank seal for a leak, as that can cause a lean condition. You may want to check your air horn adapter to see if it has a tear, that could also create a lean condition. The MAG side does not usually have issues with leaking seals...

Spray a little carb cleaner, WD40, or even starting fluid around the air horns with the engine idling. If you get a change in idle, you may want to tear into things to check that adapter. Which is a PITA to get in to... just saying.
 

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Discussion Starter #5
Lol ok, these sleds not as easy to work on as the old ones. The side I'm concerned about is the mag side, I did a compression test on that cylinder it was at 100. Sled has not run since March, so not sure if that makes a difference.
 

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100 is pretty low for the 800, I would be a bit concerned. What was the compression on the other side?

You may want to pull a plug and put that side piston to bottom dead center and take a look with a light or better, a borescope. You can also pull the exhaust and check the piston skirts for damage, that may be able to show something, as well. The 800 has had a lot of issues over the years, when something isn't feeling quite right, do further checking...
 

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When you tested did you have throttle wide open?
Pull both plugs and then hold open and pull 6 - 7 times as hard as you can.
 

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Throttle closed plug still in clutch side. I will do compression test over doing what you have told me. Thanks for your help.
 

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Discussion Starter #11
Hi Dan, so did another compression test as you said. I have 100 both cylinders, clutch side was just a bit lower say 98-99. Not what I wanted.
 

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Yikes!That stinks! Yeah you are in need of a top end rebuild. If you decide to do pistons also send the cylinders and pistons to Indy Specialties in MN and they will match up the cylinders to the pistons/rings for a nice tight setup.

The ONLY Positive to all this is that it is only the 12th of October, thankfully you have 2 months to riding season depending on where you live in the states. More then enough time to send them out, re-install, tune and get it ready for snow.
 

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Marinette County, Wisconsin. Yeah we got at least till end of December since trails can't legally open till Dec 15th.
 
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