when i put it back together it would overheat after 10 mins on riding so i was thinking and i remembered when i took the thermostat out and had to ask you guys what way it went in lol but i remembered it was rusty so ive removed my one and it works perfect it just takes a little longer to warm to ideal temp ive called a yam dealer and supriseinly its a 35 pound part from them and ebay its 40 quid without p&p so i think ill take a ride up to yamaha in bedworth and get a new one just thought idd post this so if anyone else is having this problem they have a possible answer sorted

can also be linked to air lock in the liquid coolant especially after a rebuild, squeezing the tubing whilst the engine is running after 10 mins sometimes can get rid of airlock, i had airlock in mine so i ran her with no cap on radiator and proceeded to squeez all hosing and vwala bubbles and coolant level dropped topped up problem solved

ken

it seems fixed now done 70 miles atm slowly wearing it in but ill do that tomorrow just in case thanks for the heads up