[Somik]

Hi guys. My first post! I have a Bajaj Avenger 160 Street BS6 model, and I've recently started having cold cranking issues with the bike (bike doesn't start when the battery is cold after heavy rain, and complains when left parked for a day or two even in usual temperature). The 'Low Battery' indication have started to frequently come up even after a battery replacement, so I'm pretty certain the issue is with the charging system. So I decided to test the voltages at different places in the charging circuit. My model has a 3 phase alternator (three pins come out of the stator coil), and when I tested the phase voltage of each of the pin (multimeter red probe connected to one pin, black probe connected to a screw on the chassis), I got 20-23v AC output on two of the pins on idle RPM, and basically zero output on the third one (goes up go 1.3v when I rev the engine really high). I talked to a local mechanic about this and he said this is to be expected as one of the phases is supposed to be grounded via connecting it to the chassis. I'm here to ask, is what he said right and is this a valid configuration? I did some reading before this and from what I understood the pin to pin LINE voltage (as opposed to a single phase voltage) is what goes into the rectifier and is rectified and regulated to a constant DC voltage to charge the battery. Would this work okay with one of the phases being tied to the chassis? I'm looking to test the rectifier next and I would love some folks sharing their advice on my voltage observations. I also did some reading on theory before testing so I would welcome any theoretical discussion on which configuration (star or delta) the alternator coils are connected in and whether the phase-to-phase line voltage is fed as the input to the rectifier or is my understanding wrong somewhere. Just looking to get a better picture of how the alternator connects to charging system and solve my bike's starting issue. Thank you so much!