Thanks, guys, I am glad you like the looks of the brushless 3 ph alternator. Below a few more photos from today to clarify some questions. My engines are B type, no separate cradle for dynamo, so I cannot say much about that setup. On B type I had to machine the crankcase a bit for the turned down brushless of now 68 mm diameter, just allright, you cannot go lower for the M 3 mm bolts. 69 mm would be easier but you have to get more clearance on the engine case - but then, not a big deal to do. Some places I just dremeled for clearing the cover and so on.
The homemade motor front cap got extended to reach into the engine case for having an o-ring seal, plus an extra ball bearing right next to the original sprocket to run in the triplex chain. The motor shaft is 14 mm and for exercises I made sort of shock absorber with friction plates but I´d say not so essential with my ESA mod. The rotor mass of the brushless is a lot less than the Miller dynamo so a lot less load on the triplex. The motor has 8 poles so a very smooth load for the chain, no real matter but the effects from the old destructive ESA do matter - so a big plus to have the lighter brushless magnet rotor , photos in one of my older threads here. Also performance numbers from my test jig there to find, results from half an hour runs with more than 200 W quartz bulbs, no heat problems , all below 70 degrees I think. Only component for a bit of heat sink is the three phase rectifier, to mount on a bit of alu or so, not a lot to dissipate. My first try of a typical motorbike brushless alternator regulator was very poor as it heated up the motor and regulator quickly by earthing one or two coil sets when exceeding 14 V so unacceptable ! So then I came upon the 48 V motor plus converter 48V to 13.8 V , from solar power business possibly. That setup was completely satisfying , in all respects and I am very confident it will be allright on the bike as it was perfect in my uncooled workshop test jig.
The motors come in four sizes from 100 W to 400 W , 48 V at 3000 rpm, just different lengths so you can choose what sort of power you really want. Speaking for myself I would not want more than 200 W as no idea about what to do with it, no desire to do night rides anymore. The photos below show the 300 W type on the engine, the other motor is 200 W , for comparing lengths. The China types got hall sensors under the end cap which you can skip in our case so dimensions in the Aliexpress files will be shorter when you do that mod.
I came upon this matter after reading the reports of shreddered Alton plastic gears they had at that time so searched for alternatives. And really the typical motorbike alternators today are brushless 3 phase types , just repositioned magnets and coils: Magnets in the flywheel and coils in the center component but technology is exactly same like in my chosen servo motors. I got such a type of moped alternator for testing after a mate spoke about Yamaha XT and SR miserable alternators/dynamos and put it up in the jig for output load checks. Same rectifier and converter used here and got at least 200 W 14 V from this , so another hopeful mod for XT and SR - well, not my business at this time. I am deep into homemade 4 LS brakes for two B Rapides , still confident to get them operative but a lot of headscratching to come for sure.
Vic
brushless motors:
48 V motors
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