I'm having the same issue at the moment, same year, same model. Mine has 25,000km on it.
I've tested the regulator/rectifier, and there is a definite problem there, though whether or not it's the cause or a symptom.
I've discussed this problem with an auto-elecky, and he has suggested that the stator/magnets need to be receiving battery power in order for it to generate the 35v. I'm curious as to whether or not the battery power has to go through the rectifier first, and the dodgy rectifier is preventing any power reaching stator...
I haven't had a chance to do any further tests just yet, but thought I'd pass along my queries and hope they help!
Let me know if you have any breakthroughs yourself, as I'm at a loss at the moment
