Checking for spark

Hey guys - I haven't checked for spark on a bike since my last 2 stroke, which was a 1978 CR250. None of my 4 strokes ever developed a problem where i had to check.

Went to ride my 07 YZ450F yesterday, and kicked it about a hundred times and not even a hint of it wanting to start.

I pulled the plug and it looked OK, and then i put the plug back in the cap (coil) and touched the threaded portion to a head bolt and manually turned the motor over with the kickstart lever. Could not see any spark at all.

So my question is - is this still the correct way to check for spark? Nothing has changed with these new-fangled ignitions has it? still check for spark like this?

I took my coil to the dealer this morning and it tested OK. Tried a new plug, but no spark with that either. The 2 other components left to check are my Graves CDI, and the Electrosport stator.

I have a sneaking suspicion the electrosport stator might be the culprit. Really strange though - i wouldn't think a stator or really any other electrical component would just go out while the bike is sitting in my garage for a couple months.

Hey guys - I haven't checked for spark on a bike since my last 2 stroke, which was a 1978 CR250. None of my 4 strokes ever developed a problem where i had to check.

Went to ride my 07 YZ450F yesterday, and kicked it about a hundred times and not even a hint of it wanting to start.

I pulled the plug and it looked OK, and then i put the plug back in the cap (coil) and touched the threaded portion to a head bolt and manually turned the motor over with the kickstart lever. Could not see any spark at all.

So my question is - is this still the correct way to check for spark? Nothing has changed with these new-fangled ignitions has it? still check for spark like this?

I took my coil to the dealer this morning and it tested OK. Tried a new plug, but no spark with that either. The 2 other components left to check are my Graves CDI, and the Electrosport stator.

I have a sneaking suspicion the electrosport stator might be the culprit. Really strange though - i wouldn't think a stator or really any other electrical component would just go out while the bike is sitting in my garage for a couple months.

Do you have a teenage son?

A healthy YZ450 should jump 1/8" gap easily testing the way you describe.

Thanks Gray - figured i should be seeing a spark that way.

Red - no, why?

Thanks Gray - figured i should be seeing a spark that way.

Red - no, why?

"I have a sneaking suspicion the electrosport stator might be the culprit. Really strange though - i wouldn't think a stator or really any other electrical component would just go out while the bike is sitting in my garage for a couple months."

Well, everytime I start wondering how something could possibly be moved/lost/broken/empty/dirty/full/plugged-up, I remember that I have teenagers... So I had to smile when you said; "sitting in my garage" as I picture your 17 yr old getting sideways on your bike with a big smile (and, of course, wiping it down before Dad gets home from work).

Sorry to be a cynic but I came by it honestly!

Ha Ha - Ok I get it now! No, I have no one to blame for funny stuff in my garage but me!

Still seems very weird though - bike ran absolutely perfect the last time i rode it a couple months ago. How does an electrical part just go bad just sitting in a garage?

I have a diesel pu and the service engine soon light came on in august. Its the glow plug sensor gizmo ($150 for the dealer to diagnose). Its a $100 part and i've been putting it off wanting to spend the money on my 450! Well its been in the low teens lately so i ordered the part. Guess what.......now the SES light is off and the truck is starting perfectly! Like you said how can these electrical parts go bad (or repair themselves) just sitting around.

12-18-08: Update SES light back on last nite ...ha ha!

One way stuff like this happens is loss of contact at the terminal connections. This can be for a variety of reasons, like corrosion from moisture intrusion, physically weak or damaged terminals, etc. I bears checking before spending up for a part that may not be bad.

Make sure your kill switch button is not stuck. I have seen this happen before.

yea, kill switch is one of the first things i checked

Gray - good idea - i'll check all my connectors first for corrosion. I do have a brand new moose stator already mountedin a new ignition cover just in case something like this happened

Did you try a new plug....sometimes they short out way down inside the shell

and it is sparking but not at the electrodes....Try a new plug before you go nuts changing things.......

yep - one of the first things i tried - new plug and disconnecting kill switch

Wow that is a weird one......you "Un-plugged and plugged all the connectors" Checked the ground wires .....I'm thinking out loud (it's 4:00am ) Just wondering, do you have a heat gun or hair dryer? remove the ign.cover and try heating that area up a bit and see if that does anything...Thinking moister might be playing a role here....I'm kinda stumped at this point other than checking the stator out put....

haven't had a chance to unplug/replug all the connectors yet - prob do that on sunday - just too busy til then.

it has been very rainy over here the past couple weeks, and hawaiis climate is pretty corrosive with the salty air even though i'm several miles from the ocean. i really hope it's just a connector and not my stator of cdi

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