How to torque flywheel bolt

Humm, I am have to question the Masters here. I have always prevented torqueing on the opposite ends of small engine cranks fearing that it could twist the centerlines out of true. I use either a strap wrench on the flywheel or an impact wrench, Maybe I am off base here but it seems that say 80 foot pounds of torque to tighten a flywheel is a lot to ask of a crank that only produces about 10 foot pounds of torque. I should bench test my thoughts about this on an old crank.
 
I suppose, I always figured that 10 ft. lbs. was an average over 720 degrees of rotation on a 4 stroke, and that all the force required to maintain that average was developed over 180 degrees (ignition stroke). For the other 520 degrees the motor is developing varying levels of parasitic drag.

In addition, I always used the output side to lock if a stock flywheel key was specified by the rules. If you lock from the flywheel, ignition timing will retard during tightening. If you lock from the output, timing will advance during tightening, so you'll end up with the max timing advance legally available.

JMO
 
Good points made Bob. The degrees of power out put takes my guestamation up to 40 foot pounds instead of 10.
I think some of my concerns of deforming a crank came from some warnings of torqueing the opposite ends of multiple piece 2 stroke cranks.
 
I hear about lapping the flywheel and stuff like that do I need to do anything like that before I torwue it down. We never pulle the flywheel off just the cup.
 
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