Went for a ride today and on the way home the tach Stopped working and the top(rear) cylinder was not firing. Replaced coil and rectifier along with plugs. Still no tach or fire in rear cylinder. Coil tests fine. I would check jets but it appears to be electrical considering no spark and no tach.
Any suggestions?
Bike has always run great with no issues till now.
It's an MC-16 ('87) with 9k kilometers.
Please help

Have you checked pick up coils at flywheel? If its just on one cylinder and ht coils are good I'd check pick up resistance. Also make sure your connections to ht coils are good and there is no burning around wires or connectors. Good luck!

Replaced cdi for rear and its firing better now. Still missing a tiny bit and tach is a little off so I'll replace the other cdi and see what happens

Found out rear cylinder isn't firing on idle but will fire at 3k RPMs or higher. Under 3k tach drops to zero. This has had me scratching my head for a little while.

Any suggestions?

Could be a duff battery, dirty/faulty pickups, duff coil
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