QuestionQUESTION: came in noisy, sprocket shaft nut loose, put set of wheels in it & new rings & slugs, IN valves & guides (ex side ok, repl in 01, all got new seals) got anything needed while cases split, got a new s&s E, bench leakdown test 2%, customer rides bike 30 miles & fouls rear plug (only), I bump #38 jet to #265 & reset carb, same thing happens on road test (main @#66), I test coil & primary side fails test, replace coil & wires (5ohm coil & stock prestolite ign) 30 miles & foul rear plug, wtf, float level @ min, next going to try #64 nain as cust says this happens after a high rev throttle drop. God, only with a 79 xl. other than that all else is well. Think Ive laid it all out. Oh stock s&s a/c (paper), drags, 12v all around, although I dont know if that is so during event, mix screw out 1 1/4, going to test ride today if I can get a rider - im not able to ride anymore -- oh yes this didnt happen before I worked the bike (oh course). stock cams. there are plug inserts in the heads (loosing ground @ rear head w/ high rev harmonics?) oh yeah, old coil would only jump 23kv, new does 35kv. any & all suggestions are appreciared.
ANSWER: A few questions. When you say new rings and slugs. What is a slug? Did you split the cases and replace anything? When you replaced the rings, did you hone the clyinders? What was the piston to cylinger wall clearence?
Mike
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QUESTION: slug = piston, cyl's honed, then ball honed, then washed w/soap & water, then lightly oiled; .002 clearance slip fit w/feeler guage- tight. The rear plug is not getting oil fouled. Also, ring end gap .010. The plug is getting gas fouled. the front one is getting good color. It makes no sense.
AnswerIf your plug is getting gas fouled then you have an ignition problem.
I would start by checking the new coil and plug wires. Even though they are new, they might be bad.
If all the ignition checks out then check for a intake leak and lifters to tight.
Good luck and happy riding
Mike
