wondering if anyone else has ran into this issue, any it may be my own fault but looking for some thoughts on this.

current around 600 miles on my 800. the last few days it was a little hard to start...it would start then sputter and die and took me ages to get it running. a lot of fuel smell when trying to start it the third or fourth time (which makes sense).

I noticed after I finally got it running and went for a good ride it was getting extremely hot around the air box. this prompted me to remove and inspect the filter when I got home. the filter didn't look overly bad but when I cleaned it, it was definetly very dirty. I cleaned it oiled it and installed it again.

what did concern me was that there was oil in the airbox. not a lot, maybe a couple ounces tops. just lingering around in there. the shop tells me the service bulletin / recall is only for the 400/500 and they haven't seen this on an 800.

wondering if possible that a clogged filter caused some back pressure / breathing issues? anything else I should look out for. seems to be running much better with the cleaned filter as it should, but anything else I can look out for before going on an long rides? I also checked the oil when cold and its at the top of the XXX's on the dipstick but doesn't appear to be overfull at cold.

[2015 Z Force 800 53/Trail EPS]

Not sure what the CForces have on the airbox inlet but the ZForces stock come with a bag prefilter that slips over the intake tube. When that prefilter gets plugged up, it causes excessive vacuum inside the air box which pulls harder on the crankcase vent tube moving more oil and vapors from the crankcase to the air box. The other thing that causes excessive flow from the crankcase is extra blowby. This happens when the rings no longer seal well to the cylinder and ring grooves. This happens with age of course but also happens very quickly when abrasive particles get past the air filter. Many who kept the stock CFM filter had this issue or those that didn't properly oil or service their foam filters. Warm it up well, then open up the box and run it. The crankcase tube vent port should be visible. Give it about a 1/4 throttle and notice if you see a a strong flow of gasses coming in. There will always be some...but usually not too noticeable.   

Thanks for the advice. Fliter was plugged solid. Cleaned replaced and all good.