About the new type impeller.
The new assembly includes a longer shaft, made of a darker steel. The new type impeller should be matched with the new type pump shell. I am in need of a wp replacement as I noticed the coolant disappearing slowly without any apparent leak. I will mount the older type shaft since I have it on the shelf and keep the old impeller and wp pump shell.
My bike is a 990, has 50k kms and was made in 2006