have you got a multimeter? If so - check the voltage across the battery terminals with ignition off (shoudl be around 11.8-12.8 when charged), and when running (should be about 13.6~ volts)
If the voltage is not higher when running then your charging circuit has a problem.
If the voltage is low with the ignition off (e.g. 10v) and you've just charged the battery, then you may have a dead cell in your battery, though that would be unlikely on a new battery unless it was perhaps left on charge all the time since you got it or has been damaged some other way (idk what).
If your engine-running voltage is not higher as it should be, imho first thing to check would be just inside the left-hand side of the frame, about where the subframe starts and where the weld-seam is on the main frame spars. on the inside there's a thing bolted to the frame (rectifier i believe). That has a plug going into it from the underside (3 pins iirc). If that's not plugged in properly, or has corroded contacts, that would mean your charging circuit isn't happening and would give you that sort of running-flat along-the-way type issues as you describe.
If that doesn't work then I'd perhaps be looking at contacts in the plug which comes out of the stator etc. I'm not sure what the voltages are supposed to be on those plugs but it'll be in ther service manual.
Btw if you don't have a copy of the service manual... obtain one. There's pdf downloads to be had online (for gen1 anyway).
Voltmeter across the battery terminals should tell you what's going on tho
hope that helps.
If the voltage is not higher when running then your charging circuit has a problem.
If the voltage is low with the ignition off (e.g. 10v) and you've just charged the battery, then you may have a dead cell in your battery, though that would be unlikely on a new battery unless it was perhaps left on charge all the time since you got it or has been damaged some other way (idk what).
If your engine-running voltage is not higher as it should be, imho first thing to check would be just inside the left-hand side of the frame, about where the subframe starts and where the weld-seam is on the main frame spars. on the inside there's a thing bolted to the frame (rectifier i believe). That has a plug going into it from the underside (3 pins iirc). If that's not plugged in properly, or has corroded contacts, that would mean your charging circuit isn't happening and would give you that sort of running-flat along-the-way type issues as you describe.
If that doesn't work then I'd perhaps be looking at contacts in the plug which comes out of the stator etc. I'm not sure what the voltages are supposed to be on those plugs but it'll be in ther service manual.
Btw if you don't have a copy of the service manual... obtain one. There's pdf downloads to be had online (for gen1 anyway).
Voltmeter across the battery terminals should tell you what's going on tho
hope that helps.