YZ 250 2007 lost spark, ran diagnostics all good

[PawPaw]

As will I.....but I would add, If I failed a coil with an ohm meter, I would back it up with the tests I refered to above. plus I don't know anybody who has never replaced a good part, but if I test it a couple different ways and not rely on one test that some 4 eyed pencil protected engineer came up with, then I'm more comfortable with my diagnosis. But too each they're own, I'm only speaking from my 30 years of field experience and am in no way telling you your wrong, go with what your familiar and comfortable with.

I respect your background as I too have 45 plus years of experience in motorcycles repairs and have been a service manager for one of the largest bike shops in the south serving 5 different brands of street, dirt and other equipment. Each of us has developed our own ways and we are both most likely to continue as we feel best.
I speak from my experiences and you speak from yours and that is good to deliver more than one viewpoint.
What does come to lite here is that the person posing the original question has really tested nothing, but rather is just telling us everything checks out to be ok. If that were the case the bike would start and run correctly as I think you and I both know that to be a fact.

Paw Paw

 

[2strokesteve89]

Steve, I am not sure what meter you are using, but my cheap meters show a difference when testing for continuity on a harness. The ones I test on a motorcycle are easy! The ones on a tanker or tractor and semi make you a little more resourceful. (Ask me to show you a shop made "test plug". Sometime.)15 years ago the industry made it possible for someone to troubleshoot without needing to know how to build one.

Matco and snap on vantage pro.....I guess my whole point was for example that if you show a non active circuit that may have one strand of wire connecting it at one point show continuity. and then put a load on the circuit the weak connection would certainly fail, if though I checked the circuit live with a voltage drop test. I would find the problem very quickly,it has nothing to Do with my ohm meter but everything to do with how I check for faults. I know this has almost nothing to do with the OP's issue, just trying to clarify the point I was making as I was winding down the rabbit hole.

 

[ossagp]

I bet we would all agree that chasing spark can get pretty frustrating.

 

[2strokesteve89]

I bet we would all agree that chasing spark can get pretty frustrating.

Especially if it runs and is an intermittent miss. Or only dies when hot and then restarts shortly afterward, and then you have a window of a few minutes to check it can definately be frustrating.

 

[ossagp]

Yep.

Matco and snap on vantage pro.....I guess my whole point was for example that if you show a non active circuit that may have one strand of wire connecting it at one point show continuity. and then put a load on the circuit the weak connection would certainly fail, if though I checked the circuit live with a voltage drop test. I would find the problem very quickly,it has nothing to Do with my ohm meter but everything to do with how I check for faults. I know this has almost nothing to do with the OP's issue, just trying to clarify the point I was making as I was winding down the rabbit hole.[/QUOTE

Especially if it runs and is an intermittent miss. Or only dies when hot and then restarts shortly afterward, and then you have a window of a few minutes to check it can definately be frustrating.

Maybe one of the most frustrating things electrically that I ever experienced was a bad circuit on a set of clearance lights and a "nazi" at a scale house.