Crankshaft play

[Walt_M.]

It would probably be worth your time to put a dial indicator on the end of the crank to see what the clearance is. If it is over 0.006, you may well have more as yet uncovered problems. I would hate for you to put in the kind of work yours is going to take, judging from the photos and have it blow up a mile or so into your first ride.

[munkyfistfight]

Now my question is........how tight does this nut have to be on the crankshaft? I can't see a way to measure the torque on it. Should it just be tight enough that the shaft doesn't move anymore?  I only ask because I can't find a wrench that'll fit over the nut. My adjustable wrench will fit, but I don't think I could tighten it down enough with that. Will the lock tab hold it in place once it's tight enough?

[motoracer8]

Walt, the numbers you quoted are rod bearing clearences, and you are quite right they are small. Where I got the crank end play numbers, was from the Yamaha tech dept. I repaired a Vision engine some years ago that had been run out of oil, It ruined both rod bearings, one main bearing, and the thrust bearing surface cast inside the crankcase. If you look on page 3-34 of the factory shop manual you will see what I'm talking about. The damage to the engine exceded the value of the bike, crankshaft $600, Crankcases $400, This was when you could still buy parts for them, and there were not alot of junkers around. But the owner wanted it repaired, so I welded and machined the crankcase, had chromecraft fix the crankshaft, and I resized the rods. He did most of the assembly work himself, I assembled the bottom end so I could get the end play right. He rode it untill 2001 without probblems [with oil] and sold it to buy a Suzuki.

   Ken G.