Regulator/rectifier getting hot

My stator cover and r/r are to hot to touch after 5 mins of running.
I have tested both and they are within spec. My Bike is an xj600 1991, has anyone experienced this before

 

how hot is hot? do you have IR heat temp gun?
Can you keep your fingers on it for 5 seconds or more w/o letting go?

 

Cannot keep my finger on it for any longer than 1 sec. I do not have an ir heat gun

 

hot rectifiers are usually the result of bad connections , usually on the red wire from the fusebox to the rectifier, do you have the original glass type fuses in the fuse box,
if so an upgrade to blade type fuses is recomended
also try cleaning up the connections on the rectifier and earth connections
try putting a multimeter across the battery terminals and read the voltage the rec/reg is giving out

 

Blade fuses fitted , connections are clean, gvoltage when running 14.2v increasing to 15.2v when r/r gets hotter.

 

So thinking that year / model uses a shunt regulator (brushless), which means any excess power created by the AC Generator is directed to ground. That can be considerable wattage and if you are running without loads (headlight off, LED conversion) then it will exacerbate the heating.

I would determine if it is indeed a shunt regulator and if so do a bit of research on that - some of the reading I came across mentioned 170 degrees, which would be very warm to the touch

 

Your regulator is toast and is trying to toast everything else. Don't run the bike until you sort this, else your ignitor will die.
If, as mentioned above, your bike uses a PM alternator, you should fit a series regulator, which gives the stator a much easier life.
The Shindengen SH-775 is popular amongst the Suzuki crowd, and good used ones can be found from Polaris and Sea-Doo breakers for as little as $30.

If you want a couple of hours of reading, google SH-775 series regulator and dead stators.

 

Many thanks guys, I'll do a bit of research