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[JRH]

Good afternoon chaps.

I bought a Bullet recently (iron block, kickstart only), and have only managed to ride it 3 times due to "running out of electric" each time!

All the indications pointed to the voltage regulator (DC going in, but nothing coming out). I've fitted a Boyer Powerbox this morning, and while I see a slight improvement, it's still not right.

With the old reg/rec combination, With the headlamp on the ammeter was showing a 4A discharge, and with the lights off just a smidge over the 0, at 55mph cruising.

This morning with the powerbox i'm seeing a 2A discharge with the lights on, and about a 1A charge without, so a slight improvement but still not what I would expect.

I've had the prods out and have been measuring voltages and I have the following (all taken at the battery terminals):

Idle lights off - 11.27v (0.7A discharge)

Idle lights on - 10.30v (2.4A discharge)

Battery removed, 2000rpm - 13.9v

Battery removed, 2000rpm, sidelamps on - 9.8v

Battery removed, 2000rpm, headlamp on - Engine cuts out.

Any ideas? I'm not much of an electrician, but it seems strange to have 13.9v without the battery connected. Battery or stator coils? I've got the battery on charge now, and will measure the standing voltage in the morning.

I cannot rule out a previous owner hacking the electrics about, as when I got it there was a 60/55w H4 headlamp bulb fitted! I've since replaced it with the correct 35/35w unit. I'm wondering if the higher current draw of the bulb has fried something?

Any help appreciated,

James

[Presto]

Just a minor comment - I would have thought a 60/55w H4 was correct for a 2003 Bullet headlamp.

[JRH]

Hi Presto,

I'm not sure - Working from the 1995 model manual, it says 35/35w. Bearing in mind my bike only has the single phase alternator and the seperate reg/rec units. I do know the later 3ph models had 60/55w lamps.

Cheers

[PeteF]

Duff battery methinks.
Once charged, check voltage under load, not just standing. It shouldn't dip hardly at all.

[Adrian]

From 1999 the factory changed the lighting, you should have the four wire alternator. The yellow and amber/orange leads feed un-rectified AC to the headlamp via an AC regulator and this part of the system is isolated from the rest of the electrics, so whatever is happening with the charging system, ignition and the rest of the lights should not affect the headlights at all (and vice versa) unless you can't get the engine to run. The alternator should also have two purple wires (same pattern stators have red and black) which supply the normal charging circuit, which is where your problems are most likely lurking, unless, as you suggest, some misguided electrical hacking has been performed. As you have a new Powerbox that ought to rule out regulator/rectifier problems, so I would want to check the alternator wiring and the L/H handlebar switch and wiring for any short circuits/p.o. bodges. A.

[Presto]

A lot of confusion here I think. Sorry JRH, I thought you are saying you have a 2003 Bullet, not a 1995 model. From 2000 onward H4 bulbs are correct.

[JRH]

Thanks for the replies folks!

Presto - I referred to it as a 1995 model, as that appears to the only manual that comes anywhere close to the actual bike! The later models all seem to have the all alloy engine.

Adrian - I did see the AC regulator in the RH side pod when I first got the bike. I've just managed to find a wiring diagram that relates to what I have, which is one for a "North American Export, Mid 99 & later" which does show the 4 wire output alternator, with a seperate AC/DC system!

I've put the meter in the circuit for the AC at the regulator, and there is no voltage at all. I've uncovered a lot more hacking since, and some of the wire is 3 core domestic flex! I'm assuming that for whatever reason, a previous owner has decided to wire the headlamp into the DC side of things, quite unsuccessfully, which explains the hefty discharge when the headlamp is turned on!

I'm going to have to try and get my head around this as far as a fix is concerned - I'm tempted to wire the headlamp and tail lamp into the AC (via the regulator of course) bypassing the switch altogther, so I get the headlamp on as soon as it starts. Would there be a problem with this? That seems to be the easiest fix that I can see for the time being until I can find the time to do a complete stripdown and re wire.

I'd like to have a word with the previous owner that did this.... Grrrr

[PeteF]

JRH, It's quite a common modification to divert all the alternator output into a DC rec/reg and run everything DC (there are advantages)
Your PO doesn't seem to have made a very good job of this however.

[JRH]

That's a bit of an understatement Pete! I'm not sure what kind of job has been done yet, but I expect it's pretty dire! If the job had been done correctly, then i'm assuming it should be working correctly without the 4A discharge being shown on the ammeter. The yellow and amber wires from the stator are connected, but I don't know where to, I'm going to have to trace them and see where they go. Probably nowhere!

[Adrian]

If Matey just shifted the headlamp wiring over to the DC side, that means you effectively only have half an alternator working, three coils trying to cope with everything and three coils with s*d all to do! The Pete Snidal Bullet manual explains how to connect both sides of the alternator to the regulator/rectifier for a full DC system. Take your time over the wiring diagram and see if it can be put back without too much hassle, or if not consider a rewire with a proper Lucas RM21 alternator (or its Sparx single phase equivalent), these are better for running battery-less with more output at lower (kick starting) revs than the three phase options. I assume this is why you have the Powerbox fitted. A