Hello I'm new to this forum my name is Rick I just bought a 1985 GPZ 750 A3 with 9000 miles don't know much about the history , it hadn't been run in over a year first thing cleaned gas tank cleaned carbs noticed pilot jet screws were all the way in also spark wires one and two were reversed , any way hard starting finally after a while starts and runs pretty good but getting puffs of smoke from left side notice some oil residue on no 2 plug fires the motor and no smoke the next day it smokes again maybe piston ring of valve seal bad plugs any help would be greatly appreciated the bike is in great condition worth saving thanks
If it only smokes when you first start it and then doesn't smoke again until after it sits for an extended period it may just be the valve seals need to be replaced. You can do a compression test to verify rings are ok, and it that test does show low compression (and if the valve clearances are not tight) then run a leak-down test to find the source of the compression leak. Ed
