Archive for the ‘batteryless’ Tag

XS650: Boyer Power Box   Leave a comment

Boyer Power Box


The power box is a self regulating rectifier with an internal current and voltage storing capacitor. Connecting directly to the alternator, the output is approximately 15 volts with no current being drawn and 14.5 volts with some load. These values are just right for charging a 12 volt battery or running the electrics direct.

The unit has been designed using the latest power technology semi-conductors to provide stable, direct current from standard permanent magnet alternators.

Three types are available: Single phase, Bi phase and Three phase.

Some are available with a charging lamp control, or lighting delay circuit, which prevents the lights being turned on until after the engine is started. Ensure you have the desired unit before fitting. Single phase and Bi phase units control 200 watts and three phase units control 300 watts.

As a rule of thumb Single phase power boxes are suitable for use with most British Bikes, pre 1975 with alternators two, or three wire. Bi phase are suitable for use with most Italian and French machines equipped with three wire alternators. Three phase will suit some British machines post 1975 with three wire alternators and the majority of Japanese three wire machines.

For further info go to the Boyer site.


XS650: Simplified Electrics   Leave a comment

There are distinct advantages to doing this. Original looms had circuits, relays, safety devices, checkers and stuff that did their job back then.

Time, vibration, water, oxygen and irregular maintenance have all compounded producing electrical systems, already lacking good fusing, that will provide you with endless hours of frustration.

I rip them all out. Can’t be bothered with the drama. Make them new. Myself. With central blade fuse box. 1 for each circuit. I get a new system. Custom designed for whatever I need. Easily modified. New cables. New connections. Soldered. Crimped. Isolated. And I know what I have. Diagnosis become heaps easier.

First time you’ll freak. Second time you’ll wonder why.

Here is one of the best. An all rounder. If you can look at this and understand it you will know more about original electrical systems than most. It is elegant in its simplicity. Plug and play. Except for some peripherals it’s all there. Thanxs Jayel.

Jayel put this together, earns a beer from me…everything really except indicators…for original charging systems and ignition

Simple to adapt for pretty much anything.

doesn’t get much simpler than this…no battery, runs capacitor, permanent magnet alternator, twin coil, pamco, no real need for the key though-could put a second kill switch somewhere

The only thing simpler is total loss.

Good earth connections. Check your brushes. Maintain your battery. Fuses.

Note that if installing coated bars you may have problems starting. Check your kill switch earth connection. No earth. No go.


XS650: Permanent Magnet Alternator   Leave a comment

I don’t want to knock the original generating system. It has functioned for the last 40 odd years in one form or another. Designed to be in balance with the machine itself. And it has functioned. Mostly well.

These are Hitachi-no GM here-and have mostly given dependable service. But then 40 years ago I was a teenager. Pumping. Today I’m learning my physical limitations.

It has it’s shortfalls. Don’t you?

If you’ve ever been stranded, using an excited charging system, with a weakened battery or worn brushes you’re going to start thinking the sun has to be shining. Somewhere else. Don’t get me wrong. They are not Lucas. Thankfully. But you’re still stranded.

This topic has been thrashed by now. Over at the Garage, here and here or the Oz site or here.

I remember this discussion starting up some years ago. There is a long thread at the Garage if you want to sort through it. It’s kind of interesting seeing it all develop. Here in Germany this mod has been done for a very long time now. Getting hold of the parts required is not as cheap as it used to be.

This is basically a plug and ride mod. Will take a tech. novice with the parts and basic tools a morning to complete a points bike. A little longer for an electronic ign model.


TCI pickup in the black box 13.00…brushes are isolated…earthed through the rec.reg… if converting to PMA you will lose this and your original electronic ignition


points models have this advance unit on the right hand end of the cam, points to the left


If your bike has a crank-based electronic ignition (TCI) you will need to swap this to a cam-based ignition (points, pamco…). This does introduce some timing errors associated with valve timing. Stretched cam chain, improperly dampening chain adjuster, cam lobe wear, valve wear, malfunctioning ATU etc will all directly affect cam-based ignition timing. But. Don’t worry. The points ignitions on all other XS650s are cam-based and they run just fine.

the complete ATU mechanism..passes through the cam


If swapping from crank (TCI) to cam-based ign you will need to source the ATU-as above-if using points or Pamco. This is the shaft that runs through the hollow cam and the sprung weight mechanism on the rhs. The points or Pamco fit on the lh end. Make sure there are bearings or bushes. A good time to upgrade your coils too.

There are several ways to do this.

  • Source an RD-RZ 250-350 LC/YPVS rotor and stator. ’83 on. (earlier LC-non YPVS have a lower output)


RD350LC/YPVS stator, rotor-not here, backing plate


backing plate dimensions



remove the pickup


you only want these 3 white wires = 3 phase, the rest are not required


  • Pick up a Rectifier-Regulator. An original RD will directly plug and play. New is preferable.


Ascension Cycle Works … pma adapter … ebay


  • Source a Mrriggs adaptor..ebay? Not so sure he is making them any more!! or Ascension Cycle Works … ebay
  • Get a stator only…103 x 42 x 20…mounts directly to the adaptor…endless lists in the links at the beginning
  • Find an RR from pretty much any late model high revving sports bike running a PMA. Some will have 5 wires, some 6, some 7.
  • The colour coding will differ with brand too. If  running without a battery, connect the voltage sensing wire, typically Black on Honda, Orange on Suzuki, and Brown on Yamaha and Kawasaki to the positive output wire. If running a battery connect after the ignition switch so it’s live only when the key is on.
  • Take care if ordering kits … some are only 2 phase … those with 3 white or yellow wires are 3 phase

Just found this which deals with the topic fine.

electrolytic capacitor…use the one with screw posts…25V 10000uF


You can run this batteryless using a capacitor…25V and 10K uF. I’ve done this for quite some time now with no problem, however I get a little nervous sometimes wrt reliability. I am about to add in a small gel battery. If my alternator stops charging my Pamco requires so little current I will still get home.

small gel battery


fitted, wiring laid


easily wired in…with or without battery


83-85 RD-RZ basic data … later 86/87 have VCD-88/ND AC Generators with 13A output@5000rpm


As I say, apart from a slight risk running batteryless I like this. After adding a battery I will feel good.

It’s a bit lighter, allowing slightly freer revving. For track purposes however a total loss system makes things even easier.

One more point here. These girls are starting to show their age a little, mostly gracefully. Personally I distrust the complete electrical system and usually take this chance to rip the lot out. I then fabricate my own simplified wiring. Doesn’t take long, reduces weight, makes space and you know what you’ve got.