Samco make hose clamps which are pretty decent . go for stainless with a decent hex head as opposed to the slotted ones , much easier tightening them with a 7 or 8 mm socket . sounds like your stermostwat is a bit sticky ? As mentioned already , a cheap enough part to replace ! you can also lower the fan temp a couple of degrees so it cuts in a bit earlier ! probably a stupid question , but what condition is your radiator ? flattened fins will cause the bike to run hotter ! an air lock will generally result in water being pushed out of the puke bottle . If this isn't happening the problem leans toward a sticky thermostat . bit of a bugger to change on the roadster but will give peace of mind . Good luck !