Re: 125 force head
Probably depends upon the model--A, B, C, D---My 1988 D version has the finned head. Internally, all the heads are alike so other than the cooling fins (which I don't think do too much) they all perform the same.
Usually, if the engine had a head with cooling fins, the exhaust cover had fins too. If the exhaust cover is plain, then someone replaced the head at some point, for whatever reason.
Back to the finned head: Think about this. The only air flowing through the interior is the intake air from the top rear opening of the hood. While it is significant at full throttle and high throttle settings, this air is not directed over the fins, so how much can they actually cool over and above the water in the jacket? maybe a couple of degrees?
