Originally Posted by Head2Wind
there was discussion related to this subject some time ago, "should I 'update' a 950 engine with a 990 pump impeller and cover?'.
There was a supposed 'unofficial' view/response from a KTM engineer or something to that effect, that it was NOT recommended to perform this alteration to the cooling system on a 950. As I recall the reasoning was that the cooling passages on the 990 cylinder and head are different. When applying this change to the 950 (the change to the pump increases flow rate) there may be problems/issues related to coolant flow through the head.
That is some interesting info, Ken. I like the "supposed, unofficial" qualifier, that the passages are different. I don't doubt they are, but the 2007 990's have the old style pump.
I wonder what kind of issues will occur, due to the increased pump flow? I'm guessing there will be no noticeable difference, but I like the idea of increased flow at lower rpm, where I have the most overheating problems.