Anybody had a problem with rads or stuff on nc30, i seem to not be able to control temp, had 2 days on track and it boils, bottom rad is a bit beaten up, thermostat seems ok, not checked water pump but whole system gets hot, have put a manual fan switch in and it runs all the time on track.Flushed the system and it ran clear,seemed ok for a few sessions then boiled up again.Help please? thanks

I think thats just a problem with these bikes. Mine used to get up to over 120 degrees before I put some new rads on it (and that was with road riding not track). Although I'm sure someone with more knowledge than me (not difficult) will be along soon to tell you otherwise.

bottom rad is scrap, its common. they clog with mud, you try and jetwash and bend all the fins and its blocked solid so no air can pass, boils the bike quicker than a quick thing.
good second hand rads are v rare, most are shite and full of it just as yours prob is.
rick oliver sells custom ones just for this very reason, i hope you dont suffer from deep pockets / short arms ?

Take the rads off and flush them out with a hose to remove any crud. Some of the commercial rad cleaning products might help here if it's really scummed up.

Bend all of the fins so you can at least see light through them. This can be tedious, but it will improve the colling system performance depending how bad yours was to start with. I use a nail file for this, fits well.

Remove your fan, it will just be blocking airflow getting through the lower rad on a track bike! I also remove the thermostat on my track bike for improved flow, up to you if you think you need to. Might also be worth checking the water pump by quickly taking the cover off.

A standard nc30 cooling system will be well up to the task of track days (even in hot weather) if it's in good nick. Problem is that most aren't.

thanks for info peeps, have taken thermostat out, rad is very beaten up, no light getting thru most of it, must be main prob, having new one made at a very good price i think,will let you know how it pans out if i can afford another track day!!