I also have a 2019 800 XC and it definitely has engine braking.

Were you at a dead stop or very slow speed before going down hill?  The system will "free wheel" at a very low RPM.  Try just bumping the throttle a bit going down hill, if the 2020 system is the same as the 2019 system you will feel the engine breaking "bite" in with just a small bump of the throttle.  Once engaged and up to the required RPM you should be able to fully release the throttle and feel the resistance all the way down the hill.

Remove the top and left side plastic panels.  You'll see a fuel line looking tube that runs from the canister under the left rear fender area to the throttle body.  Disconnect the line from the throttle body and tie wrap the line to the frame and cap the inlet to the throttle body.  Alternatively, you could disconnect the line that runs from the canister to the throttle body from the canister and plug the line there.

Someone posted the official service bulletin under this topic but it appears it was promptly removed.  I believe CFMoto is keeping the temporary countermeasure on the down low as it is a modification of the emission system. 

The latest countermeasure for the "hot stall" issue is to disconnect the EVAP canister from the Throttle Body and cap the inlet to the Throttle Body.

The reason given is, when the engine is hot and the air temperature is 21C or more, the EVAP system can build so much fuel vapor going into the Throttle Body that the EFI system can't compensate for it.

Per my last post on this topic, it appears like there is now a reliable countermeasure that any dealer can implement for you to address the hot stall issue.

I called a number dealers that have implemented the current countermeasure on a number of units that have regularly exhibited the hot stall issue.  The dealers I spoke to have confirmed that it has cleared up the issue with these units.

My 800 XC also has the hot stall issue and all of the following "fixes" were applied under warranty by CFMOTO.

ECU reflash.
Valve Adjustment.
Fuel breather canister plumbing changed / re-routed.

It is still occurring.  However, the good news is CFMOTO is not done trying to correct this issue for everyone.  I reengaged them yesterday regarding the issue and have included their reply below.  Therefore, continue to engage your dealers when this issue occurs.

Thank you for contacting CFMOTO-USA.  CFMOTO-USA is fully aware of the problem you are experiencing, and our Service Team has been diligently working toward a temporary countermeasure that will yield satisfactory results to owners of CFORCE ATVs. This temporary countermeasure has recently been approved, and will be officially released soon. Unfortunately, no details can provided directly to you.

Please contact the CFMOTO dealership of your choice and arrange to have your CFORCE scheduled for a free repair at no cost to you. Your CFMOTO dealer should be instructed to call the Technical Service and Warranty Department, who are ready and waiting to walk dealers through the repair process until the official documentation is released.

We apologize for the time this has taken, and remain committed to providing CFMOTO owners with quality products and dealership services.

Best Regards,
CFMOTO

I don't have an immediate need for the 2019 CForce 800 XC Service Manual but I would like to have a copy for my records.

Anyone able to make it available?

The 800XC hands down!

My wife and I take many multi-hour rides and are never uncomfortable on it.  It takes everything we throw at it and it is a pleasure to drive single rider or two up.

The 600 or the Polaris are no where near as comfortable or smooth running.

Sheem2153, I don't know how big or highly ranked your dealer is but I would check with them to see if they can arrange to have a CFMoto representative on site while trying to reproduce the issue.  I believe CFMoto would be interested in seeing 1st hand a few machines being run under conditions where this issue is reproduce-able.  Based on my direct experience with this same issue, CFMoto and my dealer has been super responsive in trying to address this issue and my machine has had an ECU re-programming, valve clearance adjustment and some fuel system EVAP line routing changes and my machine seems to be running good after these changes.  That said, my valve clearance adjustment was done later in the riding season up here in the north east region of the United States so I have not been able to run it under hotter summer conditions when the issue is most prevalent.  CFMoto currently believes the valve clearance adjustment is the true fix as the machines they have seen with the issue have had clearances that were set too tight (under spec.) from the factory.  That said, I believe they are still interested in reviewing additional examples of machines with the issue as I am not sure they are fully ready to declare victory related to the issue with what they know today as the problem is somewhat elusive and hard to recreate after a repair is attempted.  Good luck and keep us all posted.

Thanks for the update engineereskimo.

Your experience with valve clearances appears to support CFMoto's current theory of the root cause of the "hot stall" issue.  Please do keep us posted.

I will vouch for the fact that this is a hard issue to declare victory on as I have a unit that had the ECU flashed for the P0172 error issue and it experienced a "hot stall" event after the re-flash.  That said, my "hot stall" after the ECU re-flash only occurred once in 290 miles which were logged over multiple rides averaging 20 to 50 miles each.  Additionally the "hot stall" occurred only on the hottest day it was ridden.

I have had conversations with three very helpful CFMoto dealers that have had conversations with CFMoto headquarters regarding the elusive stalling when hot drive-ability issue.  It is my understanding from speaking with them that CFMoto has been able to reproduce the issue and is evaluating the root cause so they can determine the proper fix.  The most likely cause being pursued at the moment is that some units may have had their valve clearances set a hair too tight at the factory.  Therefore, when things get really hot, the affected valves expand and do not completely close causing the misfires / stalling.  They have loosened the valve clearances to be clearly in spec on only a few machines experiencing the issue at this time and it seems to have corrected the problem.  However, with so few machines where this adjustment has been made and the difficulty of creating the issue (i.e. long rides on hot days, up and down hills with two riders on board) I do not believe CFMoto is declaring victory until they see more machines where the valve adjustments have truly resolved the issue.  The dealers I spoke to indicated that CFMoto is interested in seeing more machines exhibiting the issue so the valve clearances can be checked and adjusted if needed to see if the problem clears up in larger numbers of machines.

I have been sharing information with a dealer in Minnesota who has been working with CFMoto headquarters regarding the stalling when hot issue.  He has informed me, based on information owners have been providing, CFMoto has been able to reproduce the issue during their tests.  CFMoto is researching a revised TMAP sensor, a modified gas cap and possibly other things but I do not believe there is a formal solution as of yet. 

I agree with the previous post.  My experience has been the XC is a joy to drive and takes you where you want to go minus this somewhat hard to recreate stalling issue (does not happen all the time or every ride, it seems to only happen on hotter days during longer rides).

Keep providing information to your dealers with as many details as possible.  The dealers and CFMoto appear to be listening.

Oh.  You mean the oil alarm?

Yes, this is a non issue and is normal to beep a time or two or three when starting.  Especially when very cold out side.

Thanks for clarifying.

A brand new machine not running is "normal".  You need to find a new dealer.   

Take it back and get it fixed.  Every dealer I spoke to praises the responsiveness of CFMoto when it comes to support issues that crop up.  This problem is tough to reproduce with a 5 minute ride around the dealer's parking lot.  It mainly occurs during normal trail riding (longer trips) on hotter days (above 80 degrees F).  If yours is doing it and it is reproduce-able, get it to the dealer.  I get the sense from talking to my dealer that CFMoto is eager to get a good example machine in the shop with the issue so it can be addressed.

Danoduke,

Re-read my post closely.  As of now, there is no real fix for this issue yet.  The ECU reflash with hide or suppress the P0172 error code but will NOT fix the running issue (stalling above idle when hot).  I have contacted CFMOTO directly about this issue.  They need to get this issue under control and fast.  The numbers just keep growing regarding this issue.  If you share the ECU reflash information with your dealer be sure to be clear that the current ECU reflash does not fully repair the issue and demand that this fact is conveyed to CFMoto as part of the warranty claim.

Regarding the stalling when hot issue, I had the ECU reflashed under CFMOTO's advisement to address this issue and the P0172 error code displayed related to it.  I no longer get the P0172 error when it occurs but I still have the drive ability issue where the bike stalls anywhere between 10% and 40% of the accelerator travel when the machine is good and hot.  If the accelerator is pressed very quickly from idle past the 40% point, the stall can be avoided and the machine takes off like a rocket with no stuttering or misses.  This is not optimal and makes the bike impossible to control well but it will get you home and prevent being stranded miles from nowhere.  The engine temp is fine when this occurs and displays 3 bars on the temp gauge.  It seems to be related to a external hot issue in the engine compartment when the machine has been used on a decent length ride with two riders aboard and driven up and down moderately steep hills.  If the bike is left to cool, the normal driving characteristics return and it accelerates and runs smoothly through the entire accelerator travel again.  I reported this back to my service dealer and am waiting for the next recommendation from CFMOTO.