2013 EFI 4x4. Runs perfectly with the Rectifier/regulator disconnected but when plugged in it seems to run rich, misfires under load and is down on power. Replacement brand new reg fitted, making no difference. Local shop diagnosed too much voltage from stator and says we need to replace the CDI/ECU unit. Have replaced all the usual things like spark plug, air filter, checked valve clearances...
Any suggestions would be appreciated as a replacement CDI is $900 here and with the bike running perfectly normal with Reg unplugged im not sure that the CDI is the cause of the problem. Thank you in advance.

 

Just for giggles, have you checked battery voltage?

 

I'd suspect voltage regulator AC PN 0824-037 $70.16 from Country Cat

 

thanks for the replies.
Regulator already replaced with a brand new unit and battery also replaced (old one tested fine too), no change at all.