Charging Problems when Engine is Hot
Last summer I replaced the stator and R/R with a MOSFET type. I also bypassed the junction box and went straight to the battery from the R/R. Each stator lead and the positive wire from the R/R are protected by an inline fuse. I don't remember the brands exactly, but I think the stator is an Electrosport and the R/R is a Shindigen. If it's important, I can look up the details. Since I had so many problems with the charging circuit before, I also added a digital voltage meter to my handlebars, so I can constantly monitor battery voltage.
Here's my new problem. When my engine is cold, I think everything works like it should. I get about 12.6 V at idle, and between 13.9-14.3 V when running around 4000 rpm. My problem is that when the engine gets up to operating temperature, I'm only getting the battery voltage of 12.4 V across the entire RPM range. (On a side note, the temperature gauge usually lands around 80% of the way to red before reaching steady state. Is that normal, or should it be running a little cooler? Perhaps it's running hotter than it should, which could be the root of the problem.)
My theory is that the stator is bad even though it is less than a year old. The first one I received was bad from the factory, so I don't have much confidence in Electrosport stators. Everything is fine at low temp, but maybe after things heat up and expand, there's a short to ground. I think I could get the bike hot and pull each lead and check if there's a short to ground to confirm my suspicion.
Any thoughts? If it is a bad stator, which stator do you recommend? I'd really like one that can last more than 1000 miles. The stator cover mod might be worth doing this time around.
It would be pretty frustrating to rip everything apart again, but at least this time around I'll know what I'm doing. The worst part about the whole process is getting it to not leak oil from somewhere after taking everything apart. I still get a drip here or there. I'm not sure where exactly, but my hunch is that it's coming out of the bevel gear case shaft seal. How hard are those to replace?