Motorcycle Repair: v65 Magna overheating, v65 sabre, v65 magna

Question
Why does my 84 v65 Magna run a little hot and overheat in stop & go traffic?  I've gone thru entire cooling system and can't figure it out?

Answer
I guess it depend on what you mean by hot.  I, currently, have a V65 Sabre.  I had Magna once upon a time but it didn't fit me very well....legs and arms too long.  They were nice bikes though.  The Magna has an analog meter with a white and red zone.  Does the gage hit the red zone when driving on a typical 75-85 deg day? Does the fan come on if you just let it idle for a while and does the fan kick back off after it cools the engine down?

If the fan doesn't kick on and off it's probably the switch located on the radiator.  I've heard of folks just bypassing that switch and let the fan run all the time or put a manual switch in the circuit and just turn it on when in town.  I don't like to hear the fan run so a full time fan wouldn't be my first choice but the manual switch isn't a bad idea.  I replaced my switch with a lower setting switch from NAPA so the fan comes on at a lower temperature.  If you take in your old one they can probably match it up...at least it worked for me. I think the switch was from one of the Honda cars but I don't recall which one.      

I'd guess it's either a plugged radiator (air side or water side) or a bad thermostat.  There's not much to go wrong with the water pump except leaking and that's about all there is in the cooling except the radiator.  I suppose it could be a poor ground or connection on either sensor or instruments so you might want to check those connections and make sure they are clean and not corroded. Same goes for the fan switch.  

My Sabre runs between 4 and 5 bars on my gage in town.  The fan kicks on just before it gets into the red zone.  When I'm riding it typically runs 3-4 bars except when I pushing the throttle a little harder than normal or it's a really warm day.

Unless you actually measure the coolant temp or verify the gage reading, this type of problem can be hard to track down.  They are very simple cooling systems and if the bike is running right, it's not an engine problem.  I can't think of a way to make the engine reject more heat than it was designed to but the cooling system can reject less heat that it was originally designed to by reducing the water flow or air flow through the radiator.  

Hope this helps
Rich