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Discussion Starter · #1 · (Edited)
Hi, I need help to diagnose a failure. My kfx in first start when its cold its hard to start but starts. When I've driving for about 15 minutes and its at normal temperature working. When I turn off and turn it back on it turns on at first cranking but yesterday I was driving in the forest and I was in enduro trail. But I was very tired so I turnned off the atv for around 20 minutes and when I tried to turn on it never started, my battery dieds a friend unistalled his atv battery. I installed it in my atv, everything was working ( fuel pump and electric start)It was crancking normally but it didn't turn on. my friend battery died too another friend tow me with his atv when I was towed I shift to third gear and realease the clutch and magically the atv turned on. then I left running in neutral for the battery to charge. when the battery was charged I turned off the atv and turned it back on and it turned on easily.

The battery was discharged when I left it because as it was an enduro track the atv would turn off in parts of the road that were difficult and I would turn it on many times. But the problem that it no longer starts even though it has a new battery has happened to me several times just pulling the ATV and putting it in third gear and releasing the clutch it always starts. I already changed the spark plug, filter of the fuel pump and it always gives that problem. I did a diagnosis and it does not have any error code.

I was thinking that it could be the decompression spring and I read a lot about it in the forum but I don't know because some people comment that the crancking becomes slow but in my case it's normal. I also thought it could be the valve clearence but I have not checked the measurements but in the forum I have read that it only happens when it is very hot, which in my case was very hot but I let it rest for 20 minutes while I rested and in what I changed the battery had already passed 40 minutes and it didn't even start. I wanted to install an accel starter coil but I don't know if this could solve the problem so help me diagnose what is wrong with the atv.

my atv is completely stock it only has the mxe lexx exhaust

If your recommendation is to change the decompression spring, do I buy the oem or is there one with better performance?
thanks in advance
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