Sounds like it might be worth doing a cooling system flush (and maybe an overhaul) - this should clear the crap out and help the cooling process be more efficient
It might also be that your rad is a bit gunked up with road crap so it could be worth spraying through the fins with medium pressure water. Not too high pressure though as I believe the rads are quite delicate!
Mine always gets quite hot when ragging it so I'll let you know if it changes after I do my rad and matrix!
Did you open the bonnet when you'd stopped afterwards, and park so the rad faced into the wind and there was wind flow over the top of the engine? I find this the best thing for mine