Motorcycle Repair: oil seal, shaft drive, crank case

Question
I have a Kawasaki 1980 440 ltd (kz440d). the rod that is used to change gears, not the foot pedle rod, but the one that connects to the left hand gear changer. I am leaking oil from there and if I am correct I have to tear the whole engine down from the top to get into the lower crank case. Am I correct in that this is the only way for me to change out the oil seal?

I ask this because the primary drive gear blocks the oil seal. Therefore I would be unable to access in removing or installing the oil seal.

Answer
Hi Richard, try changing the engine oil first. That seal will leak if the oil is fuel fouled and extremely thin. Try some 20w50w oii and change out the filter. Clean the area with some Brake Cleaner in a spray can and either wipe it dry or use compressed air. Road test the bike and inspect it for the leak, it may be have magicaly vanished...it may not have. Worth a try though. If you still have a leak the seal is replaceable without engine tear down. The Primary Drive gear also known as the Counter shaft sprocket needs to be removed as does the shift lever. Drill two very small holes opposite of each other into the seal about an 1/8 of deep, use a 1/16th bit or smaller, then screw two long sheetmetal or equivelant screws into the seal. Grasp the two srews with two pair of small Vise Grips and work the seal out. Lubricate the new seal on its sealing lip with motor oil and install it with a peice of pvc pipe that will slide over the shift shaft leaving enough length sticking out to tap against, gently tap the new seal into place, reinstall the Counter Shaft Sprocket and shifter, adjust your chain and away you go. NOW THIS ALL HINGES ON THE PRESUMPTION YOUR BIKE IS NOT SHAFT DRIVE! IF YOU HAVE SHAFT DRIVE THEN YOU WILL NEED TO CHECK THE SERVICE MANUAL FOR THE PROPER PROCEDURE.  I hope this was helpful

Randy