Well after having the warning light pop up while riding very slowly in some back lanes (we're hitting 30C here at present) I decided it was about time I cleaned the rad, the K's been through every British winter since I bought it new in 2007, so 6 years worth of detritius.
Removing the bodyworks no biggie apart from the tedium of all the screws
The first three strips of radiator "vanes" from the bottom where corroded but the main core was fine so the corroded vanes got brushed out.
Then a hose from the rear from the top down, along all the remaining vanes until good flow was displayed.
All done, all bolted back and re riding the exact route that resulted in overheating before resulted in the guage barely moving from about a third from bottom
A high speed test, courtesy of a race with a new M5 (the K won hands down) at a gps recorded 151mph, followed by ticking over for 10 minutes waiting for my riding buddies, resulted in the same one third up guage.
Some points I feel:
- The front mudguard is a poor design, too short and funnels muck onto the rad
The inverted triangle shape of the rad is daft, especially as the fan resides at the bottom of the inverted triangle right behind where all the crud flows onto.
The "vanes" between the cores are too fine and as such clog up if so much as a gnat hits them
The radiator "guard" whilst protecting from larger stones etc is a poor design, I'd have thought a louvered design like dirt bikes have would have offered better protection.
Now that the three rows of core no longer have vanes on them on mine there's no way they can clog unless I go riding in ploughed fields and from my tests it doesn't appear to have negatively impacted cooling capacity at all (which was a suprise)
Halfway through as seen from my webcam