After 2 loose flywheels events within 1st 2 months daily running, I tried an Economical non-machine shop once & Done fix attempt almost 1 1/2 yrs ago. After cleaning & repairing the Gouged out shaft grooves & replacing factory set screws with hardened replacements, I reinstalled the hi temp Heated Flywheel Hubs onto dry ice Chilled main shaft using Red Thread Locker coated set screws tightened with a Larger, file Tapered Allen hex wrench, hammer tapped deep seated into set screw for max non-strip hi torque Tightening...After room tempeture Normalizing, No more loose flywheels so far....I did Red Paint dot index Mark both shaft ends to flywheels & check alignment frequently for any new slippage...If any future maintance Removal of flywheels is necessary, a butane mini-flame torch is expected to release the Red thread locker....I suspect my loose spring govenor/slower speed mods combined with the stock high compression torque Kick activated the flywheel slippage....tom..