My 2016 zforce 500HO is filling the air box with oil . The other nite I was out for about 1hr and when I got home and pulled the drain plug from the air box and probably 1/4 cup of oil drained out . The bike has 190 km on it and I have already added over 1/2 litre of oil . It is at the dealer now and they have been talking to the head service rep for Cfmoto Canada and they admit they have a problem and are trying to come up with a fix .
  I did a lot of research before buying but am having second thoughts
Have been reading some post and just to let you know it does not matter if I drive fast or slow and no it has not been  tipped even slightly the last time out .

[2015 Z Force 800 53/Trail EPS]

Sounds like she has a broken ring. Can and does happen on new machines more then people think. If it is this, shouldn't be a tough fix.

They checked the compression an it is 145 so the dealer did not think that is the problem

[2015 Z Force 800 53/Trail EPS]

Oil gets pushed up the crankcase vent by crankcase pressure, and the only place it gets that is from the cylinder area so it's related to piston, rings, head gasket or cylinder...unless..it has a boat-load of exhaust back pressure and its blowing by the exhaust valve seals....or it's very over filled on oil.

I am starting to push the dealer hard for a fix and will keep everyone posted . What gets me is the bike works very good for a 500 lots of power and a top speed of about 60 mph .

You should not have to push your dealer.
There is a TSB for this problem.

[2015 Z Force 800 53/Trail EPS]

I am starting to push the dealer hard for a fix and will keep everyone posted . What gets me is the bike works very good for a 500 lots of power and a top speed of about 60 mph .

Yeah that doesn't sound like one with much of a problem. Here's another thought. On many other machines like my Kawasaki, the crankcase vent is ported into the inside of the air filter so as it pulses it can't get dirty air back into the tube..however, when the air filter gets restrictive as it gets overly dirty, vacuum inside that area increases and pulls harder on the tube which pulls more oil and vapor into the airbox. CFM doesn't port their crankcase vents inside the filter area..at least not on the Z8s, but..if for some reason there were excessive vacuum on the air box from say..too small of an inlet port, that would have the same effect...and that you say you get 60mph says you do open it up...which would max-out the vacuum levels on the box..so maybe this is something to look at as well.  Just tossing thoughts out there.

This was a very common occurrence with the 2010-2012 Polaris Sportsman 850, and I witnessed it firsthand when my father in law bought a new '11 Sportsman 850 SE that had this happen frequently. We'd be following him, and he'd hit a mudhole with an off camber rut, come out the other side and its blowing white smoke like a WWII destroyer laying down a smoke screen !!
It was so bad we couldn't ride through it for fear he had stopped ahead and we'd rear-end him. Two trips to the dealer with no resolution, so once it went out of warranty he traded it in on a Honda Pioneer. It had damn near a half a quart in the airbox, and I had warned him about it before he bought it, but he assumed they had fixed it for the '11 model year after the owners of the '10 models had raised such a stink about it.   

We are all very curious about the new 500s, as info on them is extremely sparse, and I don't even think I've found any good YT videos that showcase them, so feel free to let us know your opinion on the 500.

The air filter is not dirty ;started doing it when I drove it home from the dealer which is about 3miles away .
The 500 ho zforce does have a crank vent into the air box .
As for the 60 mph I did that once for about 2 minutes just to see what max speed was .

Hi, I have the same problem with filling the air box with oil on my new Cforce 550 eps. ATV has been recalled and I'm waiting for the service

Problem solved ? Finally got my bike back from dealer , what took so long was they had to get the authoized repair from cf moto Canada . The repair was to vent the countershaft seal and to lower the oil level to 2.4 litres from the 2.9 litres that is called for in the service manual . They took it for a 50 minute run with no oil entering the air box I have only had time to drive it for about45 minutes and no oil in air box . So far so good . When I get a chance to go for a good distance I Will post  The results .
  I hope this is the fix because for a 500  and weighing 1200 lbs plus me and my wife the thing works very good !

On a new model there is going to be little odd things pop up. If they pay attention they should be sitting pretty good after a couple years.

I'm picking up a cforce 500 on Wednesday I'm hoping maybe they fix the issue

The reg. 500 or the 500ho?