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Discussion Starter · #1 ·
Hi fella's, i have a 08' 146 that has a weird bog between 5000 and 6000 rpm, which is a nice easy trail speed, any ideas what this could be caused by? thanks.
 

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It only happens if im riding at half throttle, if i nut it or anything i dont have they bog at all. would a sticky DMP act like that?
IDK,....have you looked under the hood and seen all the electronics that make that these things tic? lol, maybe disconnect the dpm and see if helps? Flip the choke right when it does it? Just throwin' ideas out there.
 

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If it was acting up and bogging only at elevation, a stuck DPM could be the culprit as it is not leaning out the sled as you go higher basically. Chances are you would have a WOT bog too or not reach Max RPM.

I am not in winter mode so I have to think about sled issues for a moment...

If the throttle is crisp from clutch engagement, through to 5000-6000 and bogs in that range, but the bog clears up above 6000rpm, it could be the clutch not shifting out correctly, but sounds more like an engine management issue.

The easiest way to check the rave's is pull the rave caps off and run the motor. When the engine off, the rave's will be slightly raised. Start the sled and the raves should lower (close) as the vaccum is pulling them closed. As you increase the RPM's to 4500-5000 they should open up mid way , then at 7000rpm they will open all the way.

If you have a bad rave solenoid, or even a vaccum hose leak, they might be opening too early. Also the rave stem seals can wear over time and leak allowing air to fill the bellows. Chances are with minimal mileage its not a seal issue, but a vaccum line issue. Double check the hoses going to the top of the raves.
 

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I had a similar problem at sea level - it required a switch to #20 pilot jets. Fuel mileage suffered - but the mid range bog was gone.
 

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Discussion Starter · #9 ·
I understand not quite snow mode yet, i pulled my water sled out of the trees to get it ready for fall and it is starting to feel like winter in the wind, made me think of how my other sled was running when i road it last and thought i should pull it in the shop and get it ready.
 

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If you have the time, pull the carbs and check to ensure the jets are not clogged with something. It only takes something very small to clog a jet.

Some of the '08 sleds had a carb issue, some metal filings clogging the jets. If this bog is something that wasn't there one day but there the next it could be a clogged jet.

Is there any mods done to the intake system? Extra venting to the air box? With 800 miles on the sled I would certainly service the clutches. Check all the buttons/orings for wear. Rollers should be in good shape, but its possible the sled is not shifting correctly. Double check belt wear. Are you using the 377 series belt? Stock clutching?

What about track tension and chain tension? Does the track rotate freely when turning it by hand? Is there any play in the secondary? Should only have 1-3mm of play back and forth in the secondary.

With all that, I would still look at the engine management system. If you had a clutch issue the problem would likely show up at different rpm ranges, rather than just in the 5000-6000rpm zone. Everything I mentioned should be checked regardless prior to the season.

If it was intermitent I would also consider snow clogging the exhaust or even some snow injestion on deep powder days.
 

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Hey hold my beer,
I think the problem is someone isn't properly holding your beer for you and it's interfering with your throttle control during cruising. I'd get new riding buddies myself.
 

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GF's 08 has this same issue. I have cleaned carbs several times, cleaned very dirty Rave Valves, Cleaned DPM, still need to see if Boots have a crack. I know that this issue was very prevelent in the 08's due to carb issue. most people had to replace carb sets.... Have not gone that far yet. It is interesting in that when you get past the bog, the sled flippin rips! I have seen several people post about the replacement.
 
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