Battery / charging question

My kz1000 was running perfect today, it started right up with no problem.
I was heading home and it started popping and stalling out.
Had my wife bring me tools and a jump box.
I got it running off the jumper but it kept popping and stalling and made it home by nailing it until it shut off, riding the clutch and re starting.
I got home and the battery was reading nothing and will not charge.
It was a good quality 1 year old battery luckily still under warranty.
My question is since I can't check anything until the new battery arrives is should I have been able to ride without the battery?
It does run perfectly on the jumper and stays running at idle with no battery but I can not give it any throttle or it pops and stalls.
I unplugged the rectifier and it shut off so I'm assuming it's charging.


My question

No. You won't be able to ride the bike without a battery. Odd question. Ed

I had bikes that could. Good, probably just a defective battery. Thanks

In practical terms, Ed is right, you really need a battery. But technically, it is not impossible, and in fact if specially prepared, its very possible on some kz's (to run without a battery).

The 550 I've been riding for 12 years hasn't had a battery since the day I got it running. It runs great. It uses a capacitor to smooth out the alternator pulses.

This is possible on bikes using permanent-magnet alternators. On Kz's, that means the flywheel has permanent magnets on it.

A bike really only needs the alternator pulses smoothed out at low RPMs, A 3-phase stator at higher RPMs sustains a high enough average voltage to keep the bike revving. But it will usually die at idle or some other low rpm. You can test this yourself if you are willing to risk some damage, or can just test it for a brief few seconds. Just get up to speed and have some way to disconnect just the battery while leaving the charging system intact to the rest of the bike. It will keep running, but maybe not smoothly, as long as you keep it revving. At lower RPMs, the voltage drop between alternator pulses will be too much and the bike will stall.

The major problem with running with a disconnected battery (and no capacitor) is that the regulator cannot regulate properly due to the pulsing. In the past it has been reported that when a battery became disconnected on the highway , the bike kept running but all of the light bulbs burned out and the headlight bulb actually melted.

The hard part is starting a bike without a battery and getting it to higher RPMs. That usually won't happen without a battery or capacitor.

One exception... if the battery is connected and is damaged as a dead short, then it won't allow the build up of voltage so it won't sustain any type of ignition.

There is also a chance that this behavior may even apply to an excited-field alternator which are found on some Kz's. Once you get the bike up to a high enough RPM, there may be enough power to sustain the field in the filed coil, in which case the alternator would keep producing power as long as the RPMs stay up, but this has not been confirmed yet, as far as I know.

Regarding the original post... I agree the battery is probably bad. The jumper device is taking the place of the battery... Just not very well.

You will want to do some tests after getting the new battery to make sure the charging system isn't damaged.

Even with the bad battery couldn't the OP get the bike running and connect a volt meter to the battery and determine if the charging system is working? Or is this not a valid test with a bad battery? Granted it is always best to have a known good battery installed, but just wondered....
Rick H.

Rick H. wrote: Even with the bad battery couldn't the OP get the bike running and connect a volt meter to the battery and determine if the charging system is working? Or is this not a valid test with a bad battery? Granted it is always best to have a known good battery installed, but just wondered....
Rick H.

If the meter shows the battery is being held to about 14.3 to 14.6v through all RPMs then it is likely the regulator is still ok. But without a good battery the voltage will probably fluctuate quite a bit. This won't mean the regulator is bad, necessarily, but that it neds a battery (or capacitor) to regulate properly.

It also won't be a good idea to run that way for long (without battery or cap) since the RMS voltage will be higher than what the meter registers. (Meters usually only indicate average voltage, not true RMS.)