Idled, then died, won't start

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Daytonaman
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Joined: Wed Mar 10, 2021 10:41 pm

#1 Post by Daytonaman »

Fuel pump runs as normal
Replaced plug
Has good spark
Has new bat; also tried external battery
Flywheel not spun
Thumps white cranking-weak combustion-
Poured raw gas into plug hole-no ignition.
Tried ether into air box-no ignition
FP runs fuel around normally

Would a D&M kit help with diagnostics.

Canniboomer
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Joined: Wed Mar 10, 2021 10:41 pm

#2 Post by Canniboomer »

D&M kit for diagnostics like this?.... is not so useful. It only gives various "faults" if something is left unplugged.
It could be a motor internal problem, or the VDO IACV, or maybe the idle screw is backing out = too low, or both injectors not firing?. Also the cylinder may be washed out by now for less compression, after all the cranking and direct gas into it. A couple of teaspoons of oil down the hatch is always ok to help restore that. Suggest turning flywheel manually for all the testing, rather than laboring the starter and dealing with extra 1-way bearing wear and noise while doing the checks. Give a call for parts and maybe other tips, short of yanking out the motor -- yet. Good luck!

Daytonaman
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Joined: Wed Mar 10, 2021 10:41 pm

#3 Post by Daytonaman »

Thank you CB; that keeps me going on this bike. Bought it new and it has low time. Great ride, no problems ever.
When I prime, I use 2 stroke mix.
Next I will check fuel pressure.
Plug was always dry.
Either caused backfire out the air box
Oil spews out the breather, but it always did a little
Where to put a FP test tee; b/4 or after the reg.



Canniboomer
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Joined: Wed Mar 10, 2021 10:41 pm

#4 Post by Canniboomer »

You say all stock?... if so, the ATK Dale fuel fittings will have chronically leaned out the cylinder by now. Anyway, another possible reason for lost compression. All 4 fittings MUST be gutted out at the very Least, to remove all 12 choking pieces of flow-blocking innards. Or much better is to go with the HighFlow Kit, for about 4-times the flowpath and a very quiet and cooler running pump -- never cavitating again. But stock fittings?.... pump killers at best, motor wear at worst.

Daytonaman
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Joined: Wed Mar 10, 2021 10:41 pm

#5 Post by Daytonaman »

I assume the 4 fuel fittings are the quick-connect ones on the tank. I did see a tech advice on that.
I'll try that; still want to check fuel pressure.

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