08 xp 800 bog

[NEVADASLEDHEAD]

My o8 xp 800 gets a bog after it is fully heat soaked. Takes almost 1 hour to start happening. Light throttle around 6000 rpm the engine drops down to 5000 rpm and sounds like a fouled plug. When it hits 5000 rpm it clears and goes back to 6000 rpm and starts all over. Will also happen for a split second while climbing if i let out and get back into it. Any ideas?
Stock sled except for clutching

 

[MARCUSO]

Apparently when the 800r gets the water temps up to a point, the MPEM in the motor retards the timing. This might be it. I know Mountain Magic has a bypass valve to fix this. Engine tech makes it.
http://www.engine-tech.com/shop/product_info.php?products_id=48&osCsid=g1m2ihn21agp8p53o2esk65tr0

 

[Trashy]

I have a similar thing happening with mine, (08 XP) driving me crazy!!!
Most noticeable on the trail ride in and out at half throttle or so, kinda goes flat but if you give it more throttle it pulls hard and if you back off it falls on its face... But it seems to be almost unnoticeable in deep snow or whenever it is 3/4 throttle or better. WTF???

 

[mwv]

I had near the same thing happen too, climb a hill it would run fine idle back down than run like crap again, replaced the carbs went good for 2 days, than on the 3rd it was back again.
Turned out that there was tiny plastic balls in the fuel lines and the carbs from the fuel tank. Cleaned out the tank, carbs and fuel lines and has been running great now for close too 4 months now.

 

[Trashy]

I had near the same thing happen too, climb a hill it would run fine idle back down than run like crap again, replaced the carbs went good for 2 days, than on the 3rd it was back again.
Turned out that there was tiny plastic balls in the fuel lines and the carbs from the fuel tank. Cleaned out the tank, carbs and fuel lines and has been running great now for close too 4 months now.

Don't think thats what is happening to mine; its too repeatable... will do it consistently again and again... I'm not convinced its heat soak related but I will do some testing and verify that.

 

[mwv]

Don't think thats what is happening to mine; its too repeatable... will do it consistently again and again... I'm not convinced its heat soak related but I will do some testing and verify that.

It is very possible, I found my problem after cleaning my 2nd carbs, my needles were sticking clean it up ran it than sticking again thats when I found the tiny little plastic balls. Take a look on yours maybe thats the problem. The only thing that got me was why the filter was not getting them.

 

[Trashy]

What size are these plastic balls and where are they coming from?

 

[mwv]

the balls are very tiny, they are coming from we think from when brp made the fuel tank and didn't clean it out enough.

 

[fatguy1]

Make sure your heated carbs Are not turned on. I had this happen to me, I had forgotten to turn the heated carbs off after a cold ride. The next ride it was warm and after a while I had the bogging problem.

 

[ceder]

09 bog

My 09 163 x was doing the same thing, it turned out to be FM in the DPM. Cleaned and lubed it, ran great after that.

 

[Trashy]

Had a look today, the carb heaters are off, so much for that idea

 

[f=stir]

ceder what is the fm in the dpm?

 

[ace_brc]

I had a similar problem right out of the box on my 09 took it to my dealer and he said it was the solenoid, it was sticking so he replaced it in about five minutes and haven't had a problem since.

 

[BoneStock 600]

bog

Guys this sounds like a rave valve stuck wide open to me. I have seen a half of a dozen of these this way. Pull your rave caps and verify the valves will move free. If not you have the same problem the rest of the pack has been having. Hope this helps

 

[ceder]

bogging

Sorry I should have been more clear on the FM in the DPM. It had corrosion in the solonoid, all it needed was cleaned with WD 40 and good as new.

 

[Trashy]

Guys this sounds like a rave valve stuck wide open to me. I have seen a half of a dozen of these this way. Pull your rave caps and verify the valves will move free. If not you have the same problem the rest of the pack has been having. Hope this helps

UUmmmmmm.... help me out; I'm new to this Doo stuff... WTF is an FM in the DPM and a rave cap?

 

[MARCUSO]

UUmmmmmm.... help me out; I'm new to this Doo stuff... WTF is an FM in the DPM and a rave cap?

R.A.V.E.= Rotax Adjustable Variable Exhaust. Pull the bolts and slide out the valve, clean carefully with a razor... and don't run amsoil interceptor....and don't remove big spring holding the boot.

 

[Trashy]

Thanks Marcuso... I will check them.
I run Amsoil Dominator, but it did it before i switched...

 

[BoneStock 600]

Rave Valves

You only need to pull the rave valve caps to see if the valves are hanging up. Real simple 8 mm socket and 2 bolts remove them. Then push in and pull out on the valve to make sure it is free. I bet one is stuck open. I run Amsoil Dominator and it works awesome in the xp. Dont worry about that oil!

 

[Trashy]

Thanks guys... this makes more sense considering how consistent the bog is. I will have a look when I get to work tomorrow and can test this weekend.