Intermitten problem

[Kevin]

My son has his 82 V at college, he called and says it starts and runs ok for a while and then it sounds like one cylinder drops out and  tachmeter quits working. The revlimiter wire has been cut. This problem comes and goes very abruptly. Where do I start?   

[YellowJacket!]

I would check the plug wire and see if it is not only tightly sealed into the coil but firmly seated on the plug as well.  Check that first.  Could be a bad coil - I have an extra one.  Could also be a bad plug.  My money is on the coil/plug wire as thats where the tach gets its signal from (I think) ;D

David

[Tiger]

 :) Kevin, if you haven't already done so, go down to your local motorcycle shop and buy a yard of "premium" plug wire, 2 x new plug caps and 2 x new D8EA spark plugs... ;)

               8).......TIGER....... 8)

[Rick G]

I find real wire core plug wire at small engine shops, Napa quit carrying it.

[Coil Coyle]

Kevin,
         The tach and the coil with the grey wire quit firing if the wires that come out of the case from the ignition pickups are shorting to ground or to each other. These are the three cloth insulated wires right in front of the shift lever. My RK did this for weeks until I found the frayed insulation.
         The connection into the ignition box for the grey wire could also give this symptom. The orange wire to the coil being disconnected could give you this symptom. The connection for that coil's pickup into the ignition box could also do that. A failed transistor on that coil could also do that. There is a schematic on the home page under technical/ wiring diagram for you to work from. Clean all of the connections, look for fraying and let us know what you find.

$0.02
;)
Coil

[h2olawyer]

Just a minor point - don't confuse the pickup wires with the stator wires.  There are also three of those & they are normally cloth insulated as well.  All six wires come out of the right crankcase cover, at the same location.  The stator wires will all be white (or yellow).  The picukp wires are each differently colored.

H₂O

[Kevin]

Thanks for the suggestions.

[pullshocks]

Not to highjack your thread but after reading this I may have been barking up the wrong tree focusing on carb problems

I am experiencing symptoms a lot like this at idle and to some extent up through maybe 4000 RPM with a sensation of misfiring.  But it runs absolutely neck snappingly great from 5K past red line (oops).

At idle the tach is very eratic and goes to zero quite a bit.  It idles at a basic level, sputters up briefly, then back down. 

I recently checked the spark plug wire and cap with a volt meter and it was in spec.  I also took readings on the coil and it seemed to be in spec.

I'll be taking a look at the pickup wires and TCI connections tonight.