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I've been having quite a time with my CB360's electrical system. The battery just isn't getting enough juice.

A little research has told me that those bikes have an rpm threshold that they do not charge below, but I'm not sure exactly where that line is on my bike. I'm not sure if my bike is charging at higher than 4500 rpm, but I'm sure it's below 12V at lower revs. I can't really rev the thing up too much, or my neighbors will kill me.

I've had a hard time tracking down OEM parts, and have only been able to get scrap parts that I can't be sure are good. Thus, I am now thinking about trying to find some aftermarket stuff. Can I get some recommendations for rectifiers and/or regulators?

http://www.electrex.ca makes regulator/rectifiers and stators for a whole pile of bikes. While I didn't see the CB360 on their list, you might want to email them and see if the parts from a different bike (CB400 maybe?) would work on your bike.

take it where the neighbors cant hear it--charging starts at 2100 rpm.
test at 5000 rpm minimum voltage--14.8
test at 10000 rpm minimum voltage--15.5

9000white wrote:take it where the neighbors cant hear it--charging starts at 2100 rpm.
test at 5000 rpm minimum voltage--14.8
test at 10000 rpm minimum voltage--15.5

Thanks for the numbers. I am definitely not hitting 12V at 2100. I jsut found http://www.oregonmotorcycleparts.com/ and ordered one of their rectifiers. Unfortunately they don't have any regulators right now.

You need to test the electrical output -before- the reg/rec.

Buying a bunch of stuff w/o doing the proper tests first is only going to suck away your money w/o solving the problem.

I don't think your reg/rec is faulty - I think it's your stator. The only way to know this is to check output of the stator before the rectifier . usually when a reg/rec goes bad, you get NO voltage at the battery.

Your shop manual should have details on this procedure.

The alternators on this are permanent magnet type rotor.

The rectifier is a simple full wave bridge rectifier. If you are handy with wiring, a Radio Shack rectifier will do the job.

The regulator is a zener diode that shunts to ground anything over 15.6 Volts.

Not sophisticated.

You may not hit 12V at 2100 RPM. With the engine idling, take a voltage measurement. As the RPM increase above 2100 RPM, the voltage should steadily increase. You have full output at 5000 RPM. If your battery is discharged, it may not get up to 15.6 as it doesn't have enough output to run everything and charge the battery at a high rate. Charge the battery first, then check to see if the output comes up.

Bear in mind, this a a 130 watt alternator. That is about 11 amps at 12V.

Your headlight is 37 Watt low beam, 50 watt high beam. Between the lights (front running) and the headlight, you use more than half your output. The rest is for ignition system and charging the battery. I figure the ignition system uses 40-50 watts. That leaves about 1-2 amps (20-30 watts) at best to charge the battery. If the battery is run down, it will take a long time to recharge it with the bikes system. It probably takes about 2 hours to replace the charge used in a start. I tend to kick start it and save the electric start for those moments when you stall it and need to get started again quickly.

These bikes are notorious for weak charging systems. I installed a switch on my high beam so I could turn off the light in traffic. With the switch off, I put the high beams on (which remains off) when I am in traffic as the charging system doesn't put out enough and the battery slowly goes dead. With the light off, it just keep up with the electrical load. When I start moving, I put the low beam on and the headlight comes on. I installed a voltmeter so I could monitor the voltage while I ride.

mydlyfkryzis wrote:Lots of good stuff.

Good info. Thanks much!

It's pretty rare for a voltage regulator on those UJMs to fail... but who knows? I have heard great things about oregon motorcycle parts though and I know for a fact that his rectifiers are great on cb 360s. I hope that's your problem as it's a pretty cheap fix. let us know what happens after you get it installed.

This might be a stupid question - are you sure you're working with a good and fully charged battery?

I've been through this with my 360, and it's frustrating. I think these things just weren't made to run with the headlight on, and the charging system has a hard time keeping up with the draining power.
There are some modern, more powerful rectifiers that may work. I've seen them advertised, but never tried them.
I think, and I'm not 100% on this, that all the regulator does in this system is shut the circuit off when the voltage gets to a certain point, preventing you from OVER-charging the battery (not the case here). So a regulator probably won't help.
There's a test you can run on the rect. to check it. You should get continuity between the green and each of the red/white, the pink, and the yellow wires on the rectifier and between the red/white and each of the green, yellow and pink. Nothing else should give you continuity. Hope that makes sense.
Good luck,
Chris

Thanks for all the help. I installed a rectifier from the link I posted earlier and it fixed the problem. I put a few hundred miles on the bike and am now having carb trouble . Ah, the joys of older vehicles - I thought I learned my lesson when I rebuilt my '66 mustang.