I'm telling you guys I for one am convinced, that the older and more you use them the slower the Cfmoto gets. For now it's just a theory. But I can confirm 2 Cfmoto 800 that I seen don't run as they did new mine and my bubbys. Shoot new I would get 72mph top speed and buy the time I sold it I was at 68 or somewhere close to that and my buddy can't get past 64mph? Why ?? Not sure it's weird and he has no mods.

Exept the clutch, nothing can cause that... Also, always check your speed with gps. The speedometer are NOT accurate.
Any transmission system with a belt do that (same with snowmobile). check your clutch, belt, bearing first...

How I know if the secondary cloutch is the problem , and can I fix it or I have to replace it .

I'm telling you guys I for one am convinced, that the older and more you use them the slower the Cfmoto gets. For now it's just a theory. But I can confirm 2 Cfmoto 800 that I seen don't run as they did new mine and my bubbys. Shoot new I would get 72mph top speed and buy the time I sold it I was at 68 or somewhere close to that and my buddy can't get past 64mph? Why ?? Not sure it's weird and he has no mods.

I'm inclined to agree with you. When my machine was new I saw 72mph few times and didn't even know it had a rev limiter. This last weekend (just over 1000 miles on the clock) I couldn't get over 68mph and actually hit the limiter. It's got to be drive or belt related. I'll be taking it down after veterans day weekend pulling the whole body off and fixing a lot of stuff as well as re-clocking the clutch.

Ill throw in my 2 cents of info I have observed.  The sliders on the helix seem to wear quite quickly and when they do it causes a lip to hang over the ramp part of the helix.  This causes extra drag due to more surface area plus the hang over area is not polished/machined like the face of the ramps are so it seems to cause more drag.  I filed the lip off my helix sliders and it seemed to help but you also have to remember that because those helix sliders wear SO FAST it changes the ratio because that part of the sheave is now riding lower on the ramps.  Because it is riding lower due to the helix sliders wear it also does not ride up as high so that may be the loss of high end.

We all know that belts wear and that is a loss of performance also but that is to be expected on this type of drive system.  The other thing to think of is a lot of the time the "rollers/sliders" dont actually roll and they slide.  When that happens they wear flat spots and slide even more.  But when flat spots are worn in them they create better "low end gearing" because the cam plate can ride further down in the sheave.  But because they have that flat spot it also does not push the cam plate up quite as high so you lose some top end.  There are all VERY small measured things but when you add them together and amplify them through the entire drive line it will make a difference.  I plan on ordering new helix sliders and all that and will report back with my findings as I have also seen the loss in top end (although that loss doesnt REALLY bother me).  But to be up front with everyone I am running OD weights and I will replace my belt at the same time so I will not be able to pin down exactly where my gains (if I get any) will come from.....sorry but im not pulling it apart twice just to figure it out...I dont care as long as I see the gains and the belt is a maintenance item to me. LOL

Chuddly, your are 100% right.
The loss of performance have nothing to do with our engine.

Check your clutching system.

For what i have seen, the belt is very good quality.
At 3500 km mine is like new.
I really think the secondary and fly weight are the weak part of our clutching system..

I have a CVTech Trail block primary an i know they are very good so for me, the only thing i need to improve in the clutching system is the secondary.

[2015 Z Force 800 53/Trail EPS]

I also 100% agree that the loss of top end can be clutch-related. What I still am working on is..no matter what happens to a clutch and it's ratio-ing, it shouldn't prevent the engine from increasing RPM to the limiter...even down hill with the wind at your back...lol. To my knowledge the only things that can do that is:

1. Ignition restriction as in what the limiter does
2. Fuel and/or Air restriction/limitations
3. Aerodynamics- Power -V- air resistance.

Now for mine, here's what I have been thinking about. Most of you know that I have had a tank vent check valve failure and have added an in-line check valve. That has worked very well by the way. But..that OE check valve was stuck open..why? I first though it was just a failed check flap from over filling but what if it's open because it's got dirt and crap in it..it is ported into the dirtiest area on the machine...and I know gas was washing up and out the vent and that will wash stuff straight back down into the tank. And if enough stuff does get into the tank it will collect either on he intake screen or in the fuel filter restricting flow...and lets add that after sitting a while and turning the key on, the fuel pump does take almost twice as long now to pressure-up and shut off as it did new, one would have to think at least my RPM limitations to the 6800 range may well be fuel supply-related, especially sense it runs so well all the way to it. OK, maybe it could also be a failing fuel pump but with only 800 miles on it I would hope not. I will report what I find.   

Hell, I still can't get over 55 mph. And never heard the rev limiter except one time in 4WD IN DEEP DEEP snow.  Don't want to call my dealer and say hey I tried to get to 70 ,ph and only got 55.  Feels like I should have more pedal.  Like that lil green screw is stopping it.  I thought that was something they kept on it so you didn't go crazy on a test ride, or so you don't floor it until it's broke in then removed after purchase.  But nmk says it's supposed to be there.  I don't know.

Hi I guess you verified that when accelerate the pedal to the maximum the throttle valve is to be thoroughly 90or. In my case because it does not regulate llegab thoroughly. Another thing to check is that the fuel filter was dirty and replace.

NMKawierider, that can make sense because on my Power Commander with autotune, the PC5 put more fuel specificaly at 6700 to 7500...

But before messing with that, i think you need to look at your secondary. NeXT week, i will try some helix from Artic Cat (same design as our)

Hi I guess you verified that when accelerate the pedal to the maximum the throttle valve is to be thoroughly 90or. In my case because it does not regulate llegab thoroughly. Another thing to check is that the fuel filter was dirty and replace.


On the other hand most of us performed 800 tests with the original equipment. After that we started playing with various things, tire pressure, windshield, LED spotlights, height suspencion extra weight etc. All this causes us down the final speed.

[2015 Z Force 800 53/Trail EPS]

Well for mine, rule out junk in the tank and intake filter. The tank is spotless as well as is the intake filter as best I can see it. Yes, I made an access panel for getting to the pump. Got better things to do then to pull a dozen pieces of plastic just to check that screen. Next- check pressure and volume.

Ill throw in my 2 cents of info I have observed.  The sliders on the helix seem to wear quite quickly and when they do it causes a lip to hang over the ramp part of the helix.  This causes extra drag due to more surface area plus the hang over area is not polished/machined like the face of the ramps are so it seems to cause more drag.  I filed the lip off my helix sliders and it seemed to help but you also have to remember that because those helix sliders wear SO FAST it changes the ratio because that part of the sheave is now riding lower on the ramps.  Because it is riding lower due to the helix sliders wear it also does not ride up as high so that may be the loss of high end.

We all know that belts wear and that is a loss of performance also but that is to be expected on this type of drive system.  The other thing to think of is a lot of the time the "rollers/sliders" dont actually roll and they slide.  When that happens they wear flat spots and slide even more.  But when flat spots are worn in them they create better "low end gearing" because the cam plate can ride further down in the sheave.  But because they have that flat spot it also does not push the cam plate up quite as high so you lose some top end.  There are all VERY small measured things but when you add them together and amplify them through the entire drive line it will make a difference.  I plan on ordering new helix sliders and all that and will report back with my findings as I have also seen the loss in top end (although that loss doesnt REALLY bother me).  But to be up front with everyone I am running OD weights and I will replace my belt at the same time so I will not be able to pin down exactly where my gains (if I get any) will come from.....sorry but im not pulling it apart twice just to figure it out...I dont care as long as I see the gains and the belt is a maintenance item to me. LOL

What are  helix sliders and are there aftermarket upgrades ?

Sorry...what I call Helix sliders are the cam sliders.  I have many upgrades....exhaust, EJK and so on.  I may even port and polish the head over the winter.  You just never know with me LOL

Chuddly, i think your better to work on the clutching way before a port and polish job ..
With an engine with a very mild cam like our and the low rpm capability if you gain 0.05 hp it Will be good...

Our clutching system just dont transfert all the Power to the ground and the secondary set up on this machine is way off. The shift is bad. After 50 mph, the acceleration is not very good. Its like if the engine run free with no Power transfert.
With the wet clutch delete and the Trail block primary the Power from 0-50 mph is awesome, but after that the clutching dont shift the way it should.
If we can fix that, i am sure the engine have the Power to push at least 75 mph...

Sorry...what I call Helix sliders are the cam sliders.  I have many upgrades....exhaust, EJK and so on.  I may even port and polish the head over the winter.  You just never know with me LOL

Sorry I meant upgrades for the cam sliders, I have a strange noise coming from the cvt and I want to get some parts in stock for when I take it apart for inspection, I have heard the cam sliders wear quick so I would like to get some here ready.

I've been looking at Dr Pully but i'm not sure what I need, I'm not interested in top speed I haven't been 55 mph but would like to improve acceleration with a different setting and upgraded sliders etc.