||09-29-2019 12:40 PM
Originally Posted by Will750
i havo no way of checking ignition timing at all. There is only 19000 original miles on the bike and from what i can gather without a guage there is compression there. The timing is spot on 305* degrees on the rear as instructed by the service manual. How would i go about checking the ignition timing. And if all else fails i think a rebore is the last option on this.
Do the thumb check on the two shallow spark plugs, put your thumb in the hole and crank it. Would be a good idea to unplug the other spark plug wire, in case it decides to fire with your thumb in there. You should see enough compression to blow your thumb off the hole, if you get nothing, or it's really weak, you'll know that's a problem.
Need a timing light to check ign. timing, but I'm not seeing many ways that could be off. A sheared key on the rotor maybe. Although .... Any chance the pickup coils are mixed up?
That would definitely screw up ign. timing.
edit: Another check of the ign timing - With the shallow plug connected and grounded, put your thumb in the hole, crank it. Watch the spark plug for spark to occur at about the same time as the compression on your thumb. If this happens a long time apart, good chance the pickup coils are reversed.