torqueing variator and clutch nuts

[boo]

Just watched a video on Modern Vespa about installing a new drive belt.
Something that really caught my attention was the mechanic said it was very important to use a torque wrench and torque to spec.
The variator: If the variator is torqued too tight or too loose, that can cause major problems in the engine because the variator shaft is laterally indexed by torque pressure and MUST be correct.
Too tight and it can cause excessive wear on bearings. Too loose, and the shaft can move side to side, in and out, and break the oil pump chain.

I have read many post about people using nothing more than an impact wrench to remove, and tighten variator nuts without problems.

This video has made me rethink this procedure.

[JJJoseph]

Vespas are wierd & ridiculously expensive.  I've never had a problem just playing it by feel.  Anyway, Chinese parts are so cheap you can afford to learn on the job. On airplanes you always have to use a new nut, but on scooters, I usually replace the nut every two or three times.  If it's too loose, the nut soon flies off with a helluva bang, but just tighten it up a little more the next time. If you're really worried, use a torque limiter (not cheap!)