I've removed the fan from my '07 10, and with the climate here in Oz, its become pretty much unstreetable any time except the middle of winter. I don't foresee any problems at the track, but in time I'll be installed an 06-07 CBR1000 radiator ; without taking measurements, it looks at least 30-40% bigger than the brand K item, and no doubt an awful lot cheaper than aftermarket. Together with the electric water pump, I expect it will provide all the cooling I need.
Cheers,
brian