I sought the wise advice of this forum for trouble shooting my charging system. I ended up replacing the Triumph SCR rectifier/regulator with a much better Shindengen Mosfet FH012AA unit obtained from http://roadstercycle.com/
for about 1/3 the price of the inferior Triumph part. The Shindengen regulator runs quite cool and is barely warm to the touch while powering the high beam headlight and two PIAA driving lights.
I received excellent trouble shooting advice in this thread:
In addition, roadstercycle's website has additional information. One of his best tips is to use a 110 volt light bulb of about 100 watts (I used 60 watts) to test each of the three legs of the stator. At about 4000 rpm, the bulb should glow with partial brightness. It is not fully bright because the ac output of the stator is about 60 volts, not 110 or 120volts. This in addition to a running voltage test shows that the stator can hold a load.
You can test the stator by removing the headlight and unplugging the triumph rectifier from its cable in the headlight shell. The three contacts on one side of the connector attached to the main harness, not the regulator are the three output lines from the stator. Test across each pair of the three (three tests) for both voltage and load with the light bulb. You should have low voltage at idle and about 60 volts AC at 4000 to 5000 rpm. With the bike turned off, check each of those pins to ground with an ohmmeter. It should be several megohms if the stator is not shorted to ground. Finally check with an ohmmeter between each of the three pairs (with the engine off). Mine were about 0.6 ohms each and they should all be about the same.
Some people have installed the rectifier in the vicinity of the airbox, but I don't have a good location there, so I installed it at the original location.
However, the mounting bolts are at a different spacing, so I made a mounting plate out of 1/4 inch aluminum. You need the thick aluminum so that you can counter sink the mounting holes for the plate and use countersunk 6mm flathead machine screws so that the new regulator can mount on the plate over the plate's mounting bolts. The new regulator will be mounted with the line of its mounting screws vertical while the original was mounted with its holes horizontal. You can mount the new one with bolts and nylock stop nuts. You need to mount the regulator all the way over to the left side to leave room to slide the electrical connectors on and off.
I cut the wiring harness off of the old triumph regulator to use it for the three stator wires, using the bikes existing wiring harness. Instead of using the bikes original too small positive and negative charging wires in the harness, I ran the new #10 wires supplied by roadstercycle.com and wired them directly to the battery with the supplied auto-reset circuit breaker in the positive wire very near the battery. I also pulled 10 inch or so sections of clear plastic tube over the positive wire to make sure it doesn't chafe to ground. The normal length of the charging wires supplied with the kit is 3 feet. I asked for 4 feet and it was barely enough. Ask for 4.5 or 5 feet to be safe. I used every inch of the positive wire and only cut a couple of inches from the negative wire. Jack Fleming at roadstercycle.com is a great guy to deal with. He answered my questions on Sunday, shipped first thing Monday morning and I had the very complete kit on Wednesday morning.
Here is Jack's video showing in detail how to install the wires in the connectors.
I cut the unused positive and negative charging wires off close to the connector, but long enough that they can be used later for other purposes.
The new system works very well and is showing over 14 volts when running above idle. There is a lot of good information on roadstercycle.com.
2005 Bonnie, Sleepers and Unifilter, AI gone, restrictor gone, Modre's peg kit, headlight & brake modulator, tach, NC wind deflector, gaiters, steibel, vmax mirrors, Hagons & Progressives, PIAA. http://TexasCoastGeology.com