Cure for the low end bog 2010M8??

[snowbuster]

Both m8's we have ridden the last few years do this, I was told the fuel runs rich at low rpm's, especially on the descents. We found that burping the throttle helped to keep the plugs from fouling while descending. I think the oil injection has a role in this, as the oil injection seems to not respond as quickly when you are off the throttle. I have experimented with a pod type intake with a mesh hood and it made little difference with this problem, however did add significant noise as the "silencer" is removed. You needed to ride with ear plugs. The best solution that my machine (2010 hcr) experienced was removing the oil injection and going with premix and adding 25-50% av gas. Runs way cleaner and snappier throttle response. Also reeds were checked regularly, they had no chips or cracks.with the better fuel the air fuel gauge started to work properly as well,not jumping around wildly. I have since added a turbo kit, had to take some weight out of the primary clutch weights, and it works well. In the trees when you are constantly on and off the throttle i have no hesitation or bogging. Good luck with your machine.

 

[Modman]

Both m8's we have ridden the last few years do this, I was told the fuel runs rich at low rpm's, especially on the descents. We found that burping the throttle helped to keep the plugs from fouling while descending. I think the oil injection has a role in this, as the oil injection seems to not respond as quickly when you are off the throttle. I have experimented with a pod type intake with a mesh hood and it made little difference with this problem, however did add significant noise as the "silencer" is removed. You needed to ride with ear plugs. The best solution that my machine (2010 hcr) experienced was removing the oil injection and going with premix and adding 25-50% av gas. Runs way cleaner and snappier throttle response. Also reeds were checked regularly, they had no chips or cracks.with the better fuel the air fuel gauge started to work properly as well,not jumping around wildly. I have since added a turbo kit, had to take some weight out of the primary clutch weights, and it works well. In the trees when you are constantly on and off the throttle i have no hesitation or bogging. Good luck with your machine.

Sorry, but I'm confused on a couple statements. Adding av gas to the fuel on a stock motor will hurt performance more than it should help it, its like adding diesel fuel to your car. Secondly, shouldn't you have added weight to the primary if you added a turbo? Boost should allow you to pull more primary weight, not less, since you are adding more power you can weight heavier and pull full shift faster, otherwise I'd think you'd be over reving.

 

[Uptown]

Same here 2010 m8, runs rich at idle. loads up on every decent and smokes lots if I let it idle for a few minutes. I just installed Boysen Rage cages but my stockers dont look faulty at all. I already leaned the oil injection think it runs around 35 to 40\1 oil ratio. I think i will monitor the oil consumption closer and make sure it is at 40\1, using Amsoil Intercepter since new. after that I now have a PCV and will be tuning my own map. Will be putting a A\F gauge on after the sled show. Very curious to see what it reads at the lower RPM \ throttle positions. Anyone else have ideas?

 

[Modman]

Same here 2010 m8, runs rich at idle. loads up on every decent and smokes lots if I let it idle for a few minutes. I just installed Boysen Rage cages but my stockers dont look faulty at all. I already leaned the oil injection think it runs around 35 to 40\1 oil ratio. I think i will monitor the oil consumption closer and make sure it is at 40\1, using Amsoil Intercepter since new. after that I now have a PCV and will be tuning my own map. Will be putting a A\F gauge on after the sled show. Very curious to see what it reads at the lower RPM \ throttle positions. Anyone else have ideas?

They (Cats) all smoke lots in the morning when cold and idling, when descending, just blip the throttle a little or keep it up on the idle range a little. They load up but they clear out just as fast IMO, I've never had issues with it when riding, other than the odd stutter but once the power valves open, they clear out. I wouldn't cut the oil too much, a lubed motor is a happy motor. I will post some pics of cut plugs later today hopefully, I found that has helped by opening up the flame kernel to the fuel mix.

 

[snowbuster]

The av gas didn't make a big difference down low,pulled great. The difference was at altitude the pump gas wasn't as clean or snappy. I think the premium gas we think we are buying is not cutting it. The av gas is supposed to be 100 octane, maybe that is what is helping. My gauges constantly flash the low octane code when I don't have the av gas in, sputtering etc. You are right about the adding weight to the primary weights for the turbo kit, I didn't elaborate: the boon docker weights were 78 gram in the kit, but I couldn't get past 7800 rpm. So I installed cutler adjustable weights, took some weight out and at elevation I am hitting 8050 rpm with better low end response. I think I am sitting at about 77 grams now. I have a 2.5" x162" track, which may affect this as well. At low elevations I think it does over rev, I always take it easy up the trail.

 

[Uptown]

Sooo i fired up my 2010 m8 tonight. let it run and warm up. Had it on a stand so i could spin the track. I ran it for about 15mins- 20mins, engine and coolers were very warn but not burning to the touch. WHAT A Smoke bomb!! geez it was rediculous. after it warmed up the smoke at idle was not as bad but if i hit the throttle, mid or pinned it just put out a heavy cloud. Just installed rage cages, so this tells me my stock reeds were fine. It has always ran like this hence why i leaned the oil pump when i first got it. Thinking now need to take a closer look at the oil consumption again.
I wasnt to concerned about it before but I am working on a couple doos and they do not do this! plus the 800r is a carbed model which runs great!! Also i understand when it is under load and ripping , engine and pipe are hot it does not smoke like it did tonight but Thinking my oil ratio is higher than i thought it was, definately wil be checking and adjusting it more!

 

[snowbuster]

I remember one of the dealer visits the mechanic found one of the check valves on the oil injectors was stuck open, he indicated that this would cause excessive oil consumption. I think he changed them, but I didn't keep track of the usage, so don't know if it helped. No question they run rich, enclosed trailers get pretty thick inside!

 

[Uptown]

HA funny thing. After installing the rages cages my oil linkage moved positions! now i have to get it reset to the leaner setting I had it at before. Also i remembered I used alot of fogging oil last year so it will take a good real ride at WOT tro clear her out. Must say This Cat is a Awesome machine, cant wait for the snow!!

 

[potoski]

I've got the same sled. First I took all that plastic crap off the inside of the hood, the air box. Right up to the plenum. That's the last piece the air travels through before it hits the throttle bodies. From there I fabricated a piece of aluminum with two short pieces of pipe coming off it. Slid on a couple k&N filters, a vent kit in the hood and Baaaam. No more bog. It would be easier to buy a kit from timbersled or speedwerks. No fabrication req,d with those. I shed probably 8-10 pounds. And totally got rid of the bog. A dodge diesel has less plastic to try and breathe through.

 

[swabby]

Put a boondocker turbo on it.

 

[monsterv101]

could it be the safety switch on the throttle ? that's what it was on mine. I put a tether on mine and bypassed the switch ( its the switch that cuts motor out if throttle is stuck open but not pressed like if cable freezes

 

[potoski]

I put a cold air intake on. Basically got rid of all the existing plastic and bolted on 2K&N air filters with the snow socks over them and Baaaam. Totally got rid of my bog. I custom made mine but there is a couple company's that sell them

 

[marcel.]

I put a cold air intake on. Basically got rid of all the existing plastic and bolted on 2K&N air filters with the snow socks over them and Baaaam. Totally got rid of my bog. I custom made mine but there is a couple company's that sell them

You should post some pics this sounds like a good idea