Reply To: Oil operating temperature
about 50c on a fast 70mph road on a summer day but hovers at 90c in rush hour traffic or less 80c but limit should be about 100c before its cooking itself, this confirms data on the EFi service manual on engine temp sensor ranges (only 250 EFi gets it and is for the ECU only, so you wont see it on the dash)
A fan might be overkill , as you want the radiator to not have objects on it to pass air through the back of the rear engine so it gets some air , however since you’re on a naked bike , it should get more than enough air will ever need and a 250 cooler to help it. A fan might be extra tax on the electrics (albeit a tiny tax)
There is no hard data on the 125cc/250cc from Hyosung but generally air-oil cooled engines will hover around 50c at 70mph road , assuming the sensor is in the cylinder head, anything over 100 isn’t good long term