OK what does it mean if when you do a spark test there is no spark but when you move the plug's hook electrode ~2-3 mm away from ground there is mondo spark from hook electrode to ground... Of course the front cylinder doesn't do that. It sparks when hook electrode is in contact with ground. BTW its a virago not a GS so front and back cylinder instead of left and right.
Cool.
Srinath.
Have you swapped plugs (dumb question, but...)? It sounds to me that the plug that arcs away from ground is somehow internally shorted, and the spark is jumping to ground from the hook rather than from the tip to the hook (which is grounded already). Other than that, it's like you said: WTF... :dunno: :cheers:
The Same plug sparks on front cylinder's cap, and doesn't on the rear one till you take it 2-3 mm away.
Cool.
Srinath.
have you considered a virago BBS?
:roll:
Coil + and - connections backwards?
Oh... lemme see what that looks like... I haven't touched the coil in a while... and it ran fineeven yesterday morning.. of course it acted up day before yesterday prompting me to think it was carb icing... Could have been electrical all along.
And werase... no virago BBS. Those morons are always talking about how to bolt on extra chrome... nothing useful or mechanical or remotely needing thought ever gets discussed on those girlie bike sites. yea yea my fault for owning a girlie virago... Bought it form a girl, in fact in its loooong history its all been owned by women so I guess I deserve that.
Cool.
Srinath.
OK aren't all the coils nearly the same... I mean if a 12 volt 2 cylinder bike uses 1 coil per cylinder... coudl't I shove the GS'es coils in the virago... The reason I ask is... well the generic coils are so monstrously large they wont fit in the match box sized spot in the virago's frame bracket for coils. The GS'es will I think... in fact they look like the same damn thing.
Cool.
Srinath.
It sure seems to me that the insulation in the plug is cracked, but since the problem went away in the front cylinder that sort of rules that out. :dunno: For some reason the circuit is complete between the center electrode and the ground electrode (the hook) so you can't see the spark except when there is a gap from the ground electrode and the ground. If there was a problem with the coil the spark wouldn't make it to the plug regardless of the plug's position, so I wouldn't suspect the coil.
Check the lead between the coil and the plug. Perhaps when you are changing the plug's position from grounded to ungrounded you are actually changing the position of a crack in the lead insulation.
Just a thought. Good luck.
I have to test it thoroughly. I just know the saprk to rear cyl is non existent when its put in the way its supposed to be. It could be wired backwards, the plug cap could be crap, the wire could be grounding or open... any number of things. I'll diagnose it... I am the master of diagnose...
Cool.
Srinath.
Coils are pretty interchangable, but there are performance differences because of the coil resistance. Low resistance coils draw more power, and can take longer to charge, but generally deliver more spark power. The charging time can be an issue at high rpm.
I don't think a Virago would be a big concern with GS coils. Bigger coils physically generally will deliver a more powerful spark.
The virago's coils are pathetically small... even smaller than the GS (I have to compare side by side to be sure) I just think the GS ones will fit in the space they occupy... the generic ones which are huge wont fit there... I'd have to make some custom brackets and hang them somewhere and have extensions to wires etc... Hence I am looking at GS ones.
Cool.
Srinath.
If the Virago takes the same plugs as the GS then I would think the GS coils would work. If the plugs are different, there must be a reason....
Excellent point. However they sell replacement coils for all bikes... and if its 12 volt and has a 1 coil per cylinder... well that's all that matters.. So the same coil is for the GS and virago. I could swap in the GS's plugs as well...
Oh comming to think of it... I think if you want a plug with that screw in top thing instead of the exposed threads... NGK will reference you the BP7es for the GS'es plug which is the virago's. Lemme check and make sure.
Cool.
Srinath.
Plugs change for thread length, heat ranges, etc., a whole bunch of reasons that have nothing to do with the coils.
I've used a lot of different coils in applications they aren't intended for, and never had a problem. I know high rpm can be an issue, because the coil charge time gets down to millisconds. And some big coils will draw more current than the stock wiring will carry, resulting in weak sparks.
My Norton was never so happy as when I chucked those pathetic Lucas coils that could barely throw a 0.015" spark, and stuck in those '60s Chevy car coils with a 30 thou gap!
And worse the same bloody spark plug has 2 different numbers. I am checking to see it is the coil and its getting GS coils whether it likes it or not. Yea RPM capacity and charging time... yes that stupid bike barely makes 8000.... with its monstro long stroke and torquey motor it doesn't need more but its a slow motor.
Cool.
Srinath.
Coils are OK, switching the plug in to the coils seems to switch the defect... so its the crank trigger or black box...
Cool.
Srinath.
OK crank trigger checks out... The manual says 140-170 ohms and its right at 147.5 in both. OK that means its in the junction box I think... ok I can open it... this is not the kind filled with Goo... anyone knows how to test the relays and stuff... I did it before on my eli and I used the crude method. I got a broken junction box off a ZX7 or something and took out relays from it, and started replacing then... till I found one that worked. There are only 3 so its easy. Any more scientific way to do that. Electronic gurus...
Cool.
Srinath.
OK I made a 4 pack of wires... to let the crank trigger to black box connection get inverted... like the front's coil has been put in the rear's connector and vice versa... and then I routed the front ignition coil to the rear cylinder and vice versa... so the front trigger makes the black box thing the rear needs to fire, and signals the ignition coil which in turn is routed to the front cylinder... ok now it doesn't start... at all... misfires and pops in the pipe etc... and no start... I send them the right way and the front runs and rear doesn't. Am I missing something... and whay is happening... Funny thing too... the rear cylinder is also split into the fuel pump relay... Wonder if that screwed it up... BTW fuel pump runs and works fine though.
Cool.
Srinath.