Optimal tempreture for engine oil ?
you should never give a car beans till the temps have stabilised across the entire engine block, gearbox, axel and wheel bearing and the engine oil is above 80C
the other day my tuned to death 1290 KTM at 25C ambient temps, still took more than 10 miles to reach 78C - then ragging to death you can get it to 85C
so if you're hitting 99C on an accurate gauge in the sump (rather than say the entrance into the oil cooler) inside 5 miles of gentle driving I'd say the oil is working too hard - but still inside its limits - decent modern oils can last for a bit at 300C with rubbish starting to play up at 220C









