fouling out

[Mookie78]

I have an '84 Virago 1000. Rebuilt carb, total tune up...after about 15 miles it starts to chug and will foul out the one plug. We have changed the plug cap but nothing has changed the problem. Could it be the coil? I hate to get one and that not be the cure. Thanks

[CB750F]

Could be the coil craps out when it gets hot. You can test a coil to see what the resistance is in it but you'll need a shop manual for the spec. Testing it cold won't tell you what the resistance is when it's hot but if it's at the high side on the resistance spec you can bet it will go even higher when it's hot.