100C is only 212F. I believe the maximum is 240F so you have a long ways to go. My last 3 124's ran around 100C. If that makes you nervous, contact Jim F on his website. He offers 2-3 different resistors that lowers the "turn on" temp of the aux fans. He built a special for me and my fans are on most of the time in the summer but the temp never exceeds 90C. We have a local shop that will rebuild this electric motor very reasonable so I have no fear of wearing one out. Last summer i had to take a friend to a funeral in Parker City, about 100 miles from here. It was 115F and I drove at a steady 85mph. The temp stayed at 110C. Pretty damn good for a car not designed for super hot temps.
Anziani
'93 320CE 205K
'95 E420 125K