You really don't need me to say it, so I'm guessing you're looking for a second opinion on your own thoughts: If ambient temp is cool, all fluids are at correct levels and not old? The fan is working when it should and the bike is still running hotter than it should? You got a pump that's out, or a blockage.
I know old Hondas. Not so much the Yammy. Given what I know, I'd be thinking oil pump or a blockage in the filter.
I am unused to having a radiator on a bike. Assuming your antifreeze is good and the ambient temp is agreeable? I'm still going to say oil. Motorcycles ran for decades without radiators. If the coolant is frozen, that would obviously impact engine temp, but I just don't see that happening on your ride.
I'm going with some sort of blockage with the oil. Just my 2c. Hope it helped you see things from another angle.
Everything is fine. Coolant is less than a year old, fan ok, level ok, oil is fine foe another 1500 miles (20W50) might need to go back to 10W40 maybe?
The spark plug did a double stint... 13K miles... Ill change that first...
I was riding this morning to Miami and it was fine without the DBK. 185-188 The funny thing is... the temos were climbing slowly and reach 186. It was flicking between 186-188 but never saw 187? ( That how bored i was on 95) lol
Anyobe has the same issue. Cant see 187F??? Might need to call Yamaha USA for an answer!!! Thats BS!!!
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