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Old 12 April 2016, 03:26   #11
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and run it on just petrol cos your weakening the afr putting oil in
He's just rebuilt it. Normal run in procedure is 50:1 plus the autolube for the first tank.
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Old 12 April 2016, 04:43   #12
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Plugs are new and clean, adding oil as it's a rebore with new pistons rings etc and standard practice for rebuild. So thinking stator coil, ignition coil or cdi?
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Old 12 April 2016, 12:50   #13
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no spark at the s/plugs check all earth connections are clean and tight, then check other connections, if ok check the stator and trigger voltage with a multimeter,then the switch box working your way from stator to s/plugs.
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Old 12 April 2016, 13:02   #14
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Most likely an earth or coil issue.
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Old 12 April 2016, 15:23   #15
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He's just rebuilt it. Normal run in procedure is 50:1 plus the autolube for the first tank.
with autolube jet sizes adding oil to the fuel tank will reduce the amount of petrol in the mix the air volume is fixed with the throttle opening the jets can only flow so much fluid so by adding oil you will lubricate more but be running a weaker air fuel mixture which we all know isn't good burns pistons ect, surely a better idea would be to increase the amount of oil the oil pump sends into the inlet . or am I overthinking this I grew up on 2 stroke mopeds and kh 250,s and had a few seizures in my kack handed tuning attempts
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Old 12 April 2016, 15:28   #16
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Well it could be, but it would be rotten luck to rebuild an engine and have something major die 20 minutes later. Someone else (Maiden voyage .... Big thanks to Cheshire fire and rescue) had a very similar issue recently. My money would be on a wiring issue (perhaps something came loose, wore through, got hot, shorted out).
I'm still struggling to diagnose this issue, although I haven't had much time as I was away last weekend
I have purchased a multi meter, I'm now trying to figure out all the various settings before I can test ignition components, I can't say I'm particularly confident in my electrical diagnostic abilities though :-)
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Old 12 April 2016, 15:38   #17
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Just checking the obvious, but you haven't mentioned it. Have you run out of fuel or developed a fuel issue?
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Old 12 April 2016, 15:40   #18
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Ignore that. Didnt RTFQ. Apologies.
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Old 12 April 2016, 16:15   #19
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Gone through it all and think it all fingers are pointing to the coil which now thinking aback would explain the random knocks here and there before I stripped the engine as the pack started to fail
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Old 12 April 2016, 17:40   #20
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with autolube jet sizes adding oil to the fuel tank will reduce the amount of petrol in the mix the air volume is fixed with the throttle opening the jets can only flow so much fluid so by adding oil you will lubricate more but be running a weaker air fuel mixture which we all know isn't good burns pistons ect, surely a better idea would be to increase the amount of oil the oil pump sends into the inlet . or am I overthinking this I grew up on 2 stroke mopeds and kh 250,s and had a few seizures in my kack handed tuning attempts
Yeah that would explain the lack of spark?

Modern synthetic oils burn as part of the combustion process, old mineral oils didn't..
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