I have to take my sons head off his TTR125 Yamaha to see why it's smoking and burning oil. I believe he ran it low on oil . Which Torque wrench do you guys recommend for re-assembling it. ft/lbs or in/lbs? 3/8" or 1/4" wrench? I would appreciate your thoughts.

 

Probably the 1/4 drive in inch/Lb's for doing head work.

I have 1/4, 3/8, and 1/2 drive wrenches, and find that I use the 1/4 & 1/2 drives the most.

The 3/8 & 1/2 drive are Sears Craftsman Microtorque and are well made. They're about $75 each, but occasionally sell for $40 during the holiday season. Sears quit selling a 1/4 drive, so I have a Harbor Freight 1/4 drive unit. Chinese made, but not bad quality, and much, much, lower $$.

Once I started using torque wrenches, I realized that I had been way over tightening everything. A mechanic told me (after I had purchased my torque wrenches) that if you don't have a torque wrench, and good rule was to tighten until you just feel resistance, then continue another 1/4 turn. I have tested his general rule with a torque wrench, and found the rule to be pretty close to the actual measurement.

 

Don't do it!!! He is your son...lol

 

Thanks KQ400Pilot, I'll go to sears and see what they have. I don't trust Harbor Freight for calibrated instruments.

LOL mudslinger2, I guess the cops will be at my house when I get home.