[Petet Hill]

Have a problem starting a cf 188 493cc engine in my side by side utv. Using a stobe to check timing marks. Does anyone know what  the timing should be at turnover please. Its fitted in a Loncin LX 500 utv -2.  Does anyone have one of these? Checked everything several times and cant find a reason for not starting.Appears to be firing about 30 something degrees btdc. Nice spark. Fuel. Compression tested.

[NMKawierider]

No idea what machine you are talking about but firing 30+ degrees advanced it will never start. Best check the valve timing, the rotor as it may have slipped and the pulse coil.

[Petet Hill]

Thankyou for replying.
The cfmoto 500 atv manual says 32 and 34 in two different sections?
What makes you think that 30 plus would be wrong. What would you expect it to be on a cff 188 engine?
Valve tappet clearances are correct. Line on fly wheel is inline with arrow. Paint marks on fly wheel hand pull  line up. Piston at tdc down through spark plug hole. Timing marks on cam sprocket and end of cam correct. Its a mystery.

[NMKawierider]

Thankyou for replying.
The cfmoto 500 atv manual says 32 and 34 in two different sections?
What makes you think that 30 plus would be wrong. What would you expect it to be on a cff 188 engine?
Valve tappet clearances are correct. Line on fly wheel is inline with arrow. Paint marks on fly wheel hand pull  line up. Piston at tdc down through spark plug hole. Timing marks on cam sprocket and end of cam correct. Its a mystery.

Odd indeed. I would have expected 5-15 degrees of advance at startup and idle. 30+ above 2K. But..you have the manual. This engine isn't in a CFMoto vehicle..is it. Meaning it's not a CForce,UForce or ZForce, Tracker, Snyper..ect.

[Petet Hill]

Correct. Its a Loncin Lx500 utv-2
Has a 3 plug cdi similar to yamaha but some one has put a cfmoto cf 188 500 in it. Suspect you are right and 10 deg btdc shoild be more correct but getting 30 plus. Working out how to put the 2 plug cgmoto cdi in it. Would be nice if a cf 188  cfmoto 500 owner could confirm btdc figure at start up

[Petet Hill]

Well i attached the cfmoto 2 plug cdi
But no battery on the pin out to aux relay.
Went back to the Lx500-utv o2 cdi.
I may have left the 4:pin plug off or wired the 2 pick up wires the opp eay round. Not dure but the timing light said it was correct. It fired up and revved very well but switched off ss i had left tappet covers off etc Will tidy everything up and try to find out what cured it? Think its just felt sorry for me in lock down. Will report back what he was causing the advanced timing observed. The main issue was the piston rings being seized in a closed position. Very little compression.. How this vould have happened is a mystery.

[Petet Hill]

Well ive cured this problem and the engine is running sweet. Took abit of time to get all the air out the water system.
Had to re engineer the throttle length as it was over revving and a new choke cable . Good ldle speed now.

[Petet Hill]

Well I spoke too soon. Back to 30 plus degrees advance. Will have to remove the flywheel to eliminate it. If the flywheel was slipping under power it would cause it to advance buy why the same amount each time? Could be the initial starting torque that let's it slip and then it stays there but occasionally slips back the other way at switch off or is there something stopping it slip any further ?Surprisingly it will fire up at this advance when warm but runs rough.

[Petet Hill]

Have found my issue here as i have commented elsewhere but want to conclude this thread. Found the solution actually on a rhino forum.
My utv has a 3 plug cdi same as rhino.
My reverse light was on and i had  a reverse switch faulty. A very common fault. I assumed this fault would just affect light indicators. Not so. Under a no earth situation on the reverse wire the cdi has a limiting affect. Reduces revs in forward gear and more so in reverse. Symptoms of alternate pulses switched off. Spits backfires. Vibrations and noise and in my case an advanced timing light indication.
Ordered a new sensor but meanwhile grounded the reverse wire and it now  starts brilliantly and revs up no problem. Had this fault on this project for ages. Cant believe it! Not sure if a pure cfmoto machine cdi exhibits this in the same way but would be interested to know.