[CBaines]

I recently bought (what i thought was a decent deal) on a 2016 CFMoto CForce 500 HO. I bought it from a person i have known for years, he had only put about 5 miles on it and parked it due to issues with his knees. Anyway long story short, i bought the unit in mint condition with 5 miles. I got it home and drove it around for a while and everything ran fine. After about an hour or so of riding it, it cut off on me. I started it back up, and went on with my business.

Now anytime i ride it, its not dependable because after about an hour or so of riding, it just cuts off and it's a pain in the rear to get it back started. Even if i get it started as soon as you give it gas it cuts off again. For it to work normally again, i have to let is sit for a few hours or overnight. After it's sat a while it will fire right back up and you can ride it for a hour or so again.

I had read on the forum here that some of the 2016 models have weird issues with the harness going to the fuel pump relay, so i made a pigtail like they have described here, and hooked up and was hoping that was going to fix it, but it didn't. I'm sure someone is going to ask about temperature of the unit when these issues occur the temperature isn't always the same. It goes up to 4 bars, then the fan kicks on and bring it down to 2-3, so the fan seems to be working. I am using the recommended 89 octane fuel in the system, and have even tried 93 octane but didn't help. We've checked the plug and it looks just fine, so it doesn't seem to be rich/lean at all.

I figured i'd post here and see if anyone else has had this issue, or knows someone they can ask how to fix it or what test to do next.

I need to get it into the dealership for the Cylinder Head bracket recall, but they are backed up right now and can't look at it for a few weeks. So i'm trying to resolve this other issue since i have nothing but time now.

Oh the other issue i've had with it sometimes starting it just runs up to 4k RPMS and stays there, and quick on/off of the key, and the idle is reset, so it's not a cable issue mechanically, but maybe a sensor? It hasn't done that in a few weeks though, so maybe it worked itself out.

[ctdls]

You have not mentioned what you did after bringing out of hibernation. Bad fuel comes immediately to my mind, stabilized or not. A simple spark plug, a lot of starting on/off combined with prolong idling kills plugs even with no miles.

Stock batteries do not even qualify as junk, more so if it has not been maintained properly.

Begin with basics prior to looking for manufacture defects.

[CBaines]

So we ran the tank of gas that was in it out, added new 93 octane fuel, same problem persists. It's had a new battery installed, and according to the dealership the fuel pump was replaced before the previous owner purchased it from the dealer.  The thing that boggles me is you can drive the crap out of it for the first hour then it starts acting up, which typically tells me the fuel is fine. Also sometimes when you turn on the key after this has happened you dont hear the fuel pump initialize (normally it's a loudish noise when it turns on), i had read though since it's fuel injected once the injector is "loaded" it won't prime anymore until some of that fuel is burned off(not a mechanic, so no clue how that works)

As far as the plug, it's got spark and works fine for an hour or so, and then works fine again the next day, have you seen issues where a plug will work for an hour and quit for a few hours, and be fine the next day? I had some simular issues like this with my LTZ 400 and it was just the ignition coil over heating and i had to replace it, but with these electronic models, there's not much you can do the self-trouble shoot without a PDA.  Has anyone been able to find a pigtail to allow a Standard OBD-II scanner to read from the ECU on this model?

[NMKawierider]

Just an interesting comparison, on my Brute Force when the tank check valve stick shut, it would run about an hour before there was so much vacuum in the tank that the pump couldn't pull enough fuel to keep it running. When I opened the gas cap a big woosh of air would rush in and it was OK again for..another hour or so. My check valve on my Z also failed but it stuck open and would so something dofferent but..they are the same types of devices doing the same thing..basiclly allowing air in as the pump pulls fuel out but not allowing gasses out. When yours acts up, loosen the tank lid and see what happens.

[ctdls]

Many things you can do without a PDA, it's a tool & like any other it's only as good as the person using it. No magic button that you press & it magically tells you what is wrong & fixes it self.

Starting it with the old fuel never mind running it out isn't a wise thing to do. Varnish, plugged filters all comes to mind, PDA monitors nothing regarding this.

Good that you replaced the battery, that eliminates having enough voltage to turn over & not start.....provided the new battery maintains voltage while cranking.

You need proper or near fuel pressure, the PDA does not tell you this. The pump cycling only tells you it operates, get a gauge on it & leave it on & make pressure is correct when the unit pukes.

Spark plugs.....I'm sure NMK can tell many stories how he has been haunted by a $3.00 item  I still get caught from time to time, thinking I'm smarter than the plug 

[ricksmoto]

i know this is an old thread but just in case someone stumbles upon it i thought I'd chime in, it sounds like the old fuel has left deposits in your carb or injectors , old gas does this and when new fuel is used the solids break loose and plug jets or injectors.