Hitchcocks Forum

Hi, does anyone know the true output in watts or an easy way to measure it on the 4 wire alternator stators fitted to the Bullets from 1999. Information I have seen vary between 70w and 120w. I am trying to wire in a spot light and want to know if the existing system will cope.
Many thanks Chevy

Hi Chevy. The ouputs quoted are maximums probably set at 5000rpm but all slower revs gradually reduce the output. It might be better to add all the existing loads to see what you use at the moment. So about 30 watts for ignition about 5 watts charging battery when full and nearly 60 watts for main beam and tail speedo light, so that is getting on for 90 watts, so even if you have 120 watts of output at a decent high revs you only have 30 watts to play with. I have not included indicators or stop lights as they are intermittently used, these are going to use about another 25/36 or more watts, but this can be sourced via the battery and replaced as you drive. If you already have the spot light, try it out and see how the system handles it. If you find the battery charge dimished after a ride you will have to switch the spot light on seperately and then you will have no trouble and can even use a 60 watt bulb in it rather than a small wattgae one if run with the headlight on. Sorry I don't have to hand actual outputs which is what you asked for. There are 180w alternators available at a high cost.