Re: Stator- I went through this last year, trying to decide whether to add the light or not. Decided to spend the money on the Big Bore instead.
For anyone interested, here's the whole story (if anyone else can comment or supply an easier way, let us know):
To add a headlight for a CRF150
1) You'll have to rewind the stator- the CRF150 produces pretty much nothing.
The bigger names in the US that I've been in contact with are:
Ricky Stator website
http://rickystator.com/
Baja designs website
http://bajadesigns.com/
Ricky Stator said they'll rewind the 150 stator to run 150 watts for $100 (last year price though)
Baja Designs will rewind to power a 35W headlight for $90 (didn't get what the wattage output would be but it doesn't sound like they're doing as much as Ricky stator. On their chart they rewind a 0 TTR to 110 watts so this is maybe the same?)
The other thing I looked into was simply changing the 150 for the 230 stator. Both the above companies weren't sure whether the 230 stator would fit perfectly onto the 150 and said I'd have to call Honda to determine but advised that it would still be best to rewind the 150 stator anyway as the 230 stock stator isn't meant to run headlights (only keep the battery up) although it can under the right scenario.
2) You'd then need a regulator- for lights only, you'd need an AC voltage regulator. If you want to run a battery as well (which I was interested in, due to my GPS) you'd need a a rectifier regulator (quoted at ~$45). The wiring issues will depend on what you end up with for regulators, etc (this seems to be my biggest stumbling point so far to determine). Baja Designs has some wiring info on their technical info site:
Wiring options
3) Obviously, you'll need a headlight. Which one depends on what your needs are and how much wattage you end up with.
4) Lastly, a switch to turn the lights on and off would probably be a good idea. I'm not sure if it would be absolutely necessary though, unless you had the battery (or at the amount being produced by that stator if you have a lower wattage light)
Turn around time for the stator rewind has been quoted at 2-3 days.