vf 500 f2 1986 keeps cutting power out and rev counter dies

hi new to v4s and this site i have a 1986 vf500 f2, she starts and runs great till she warms up then the rev counter drops to 0 and 2 pistons have problems sparking. checked the coils theyre not the problem any ideas where my next port of call would be. fantastic bike other than that. thanx for any help

 

You almost certainly have a defective pulse generatator coil, the one that fires the ignition coil that sends power to the tach .

They often fail when hot but work OK when cool.

How many miles on your bike ??

 

shes got just under 50k miles.thanks for the directions. i'll look into it and let you know how it goes.

 

had a 1985 magna that would not fire on 2 of the cylinders.

problem was bad solder joints in the cdi box.

one night with a beer and a soldering iron, i removed, cleaned and reflowed solder all over the board.

problem fixed.

could also be your issue.

 

:behindsofa:


IF you have 50K on a good-running VF 500, that may take the record 'round 'ere, and if it's on the original engine, extra points.

:behindsofa:

 

finally sourced the new part.for only £15.i'll let you know how it goes.

 

thanks very much for the help, i replaced the pick up coils and she runs a treat. can finally ride it for more than 20 min. now this is my favorite bike.