Originally Posted by xlite
It should be noted that less oil causes motors to run cooler not hotter. I've verified this on Rotax UL engines, HTs, and weedwacker friction bikes with IR thermometer. All the way down to zero oil which ran the coolest. The do blow w/o oil but not because of engine heat but rather localized seizure due to lack of lubrication.
Originally Posted by Pablo
I was going to say, you were just getting on it more.
and yet... as I was deliberately testing the engine and its performance, I was VERY careful to run the exact same route, the same distance (about 5mi), the same fuel, and ofc at the same speed (WOT being about all she sees lol), and as all of this was on the same day - conditions weren't a factor...
I took her out with the old oil and mix, ran the route to warm her up and check the plug. = norm
I drained the fuel, mixed up a batch w/the new and filled her up - ran the route again. = HOT
I drained the fuel, remixed w/more oil, filled her up - ran the route = norm
I'd even be willing to admit it's all in my head, as the other effects may well have been - if
the motor hadn't been so obviously hotter than normal. In addition to the "ting" of a cooling motor, a substantial amount of additional radiant heat could be felt, as well as some paint burn, a symptom I'm normally well past.
So my question is then, what would have caused not only such an increase in temperature, but one with a repeatable effect, and one cured easily by reverting to my previous mix?
I'm not denying your expertise, the very opposite actually - as now you have left me baffled o_O
I'm totally willing to try it again too, just to eliminate my own doubt if no other.
edit: again no offense, but I've now searched for anything to substantiate xlite's findings and I can't seem to find anything - could ya maybe point me in the right direction? I'll never
get this past my technician friends elsewise
(They're Yamaha outboard techs, so not as familiar with straight air-cooling)