Are they fragile, or just intolerant of heat? I thought all the fragile parts got replaced eons ago.
If you "listen" you can hear not only each shift point but when the convertor locks and unlocks. If not that then watch the tach: when the convertor is unlocked the engine looks like it connected to the wheels via a rubber band: apply just a hair more throttle and the rpm rises slightly, with no mph change = convertor unlocked. This is very noticable at low(er) rpm's -- which is where the most slippage occurs. Versus when it is locked up: varying throttle means no rpm change (unless if mph changes).
Slippage = heat generation; force a downshift at that point, and it will either lockup or at least have enough engine rpm's such that slippage is greatly reduced. [The locking torque convertor locks the parts together for no slippage. I don't know if this vintage transmission uses "variable" lockup or not, but IMO it's no better than being unlocked.]
If you are worried there are two things to do: one is get a trans temp guage. A 1996 should have OBDII, and should (should?) have trans temp available over the OBD port. It might not, as this is getting kinda old; but an OBD reader like a Scanguage etc is a plug and play operation. Alternatively you can add a mechanical temp gauge; or finally just add a trans cooler. The vehicle should have one, but if lacks one then I'd add it before long.
A motorcycle on a flat trailer isn't much of a wind load. An enclosed trailer at speed, regardless of weight, is a major wind load.
