Katana Owners Club U.K.

During the excellent WussyKat ‘21 at The Maypole (Kool Kats and Daft Dogs), Skruffy Kat developed an annoying electrical issue.
Apart from the rear brake switch sticking on, caused by the connecting spring snagging on the brake torque arm bolt The sat nag supply kept dropping out at lower rpm. Usually as I arrived at a junction/roundabout and could have done with with some sort of general guidance as to where I needed to go.
This got progressively worse on the way home and Skruffy Kat valiantly made it back onto the drive, where she promptly gave up!

Knowing the history of 80’s GSX electrics and that the alternator and the reg/rec are original Suzuki items, I bit the bullet and ordered a new one of each from ElectrexWorld plus a new gasket for the genny cover and some other bits and pieces to do a service!

Did some static tests on the alternator and the reg/rec before stripping it down.

Phase to phase resistance on the alternator were all about 1-2 ohms. A bit low I thought.

So on to the phase to ground insulation checks..


First test

2nd. Well that’s a bit Meh!

3rd phase was unstable and all over the place! So that’s the alternator fried. Didn’t bother doing phase output voltage checks

On to the reg/rec…

Using the official test sequence from Suzuki, I started with the rectifier diode forward resistance. Expecting 5-8 ohms….
All the diodes are showing open circuit, so that’s sautéed…

Battery voltage had dropped to 9volts but the Optimate charger brought it back up to a healthy 12.5 volts, which it held over a few days no problem.

Step one was to drop the exhaust off to allow me to drain the oil.
Then change the filter, while I’m there.
Remove the final drive sprocket cover, and the starter motor cover.
Disconnect and pull back the alternator leads.
The genny cover come off to reveal a truly blackened alternator!
The alternator and the cable retainers need to come off, aided by the percussion screwdriver!
Clean up the cover gasket faces and all the grubbiness on the outside.
The rubber grommet that the alternator leads pass out of the hot oily bit into the hot non-oily bit needs to be reused as you don’t get one on the new alternator. After a little bit of work you get this…

Just for info. This is what the old alternator looked like… Don’t think there’s many volts left in that!

The reg/rec fitted easily enough with a bit of jiggling of the fuse holder. The new item has more fins and is just a little bit bigger than the Suzuki original.

Nice new bullet connectors made up with a smear of dielectric grease.

All three phases wired direct to the reg/rec, easy as it’s 3 times yellow to yellow.

White-red to Green-white is the original switched phase to/from the lighting switch.

This may work….

[youtube] https://youtu.be/1_zzL_ZDLy8[/youtube]

Needs a sign in.......

Now try, first time I’ve bothered to put a video on yootoob!

Yes that works.....

did you check te link from one alternator phase to the headlight switch? terrible idea, all three phase output of the alternator should go into the three inputs of the reg rec diirectly, remove the loop that goes to the headlight, well, disconnect it and leave the wires in situ. the link through the headlight switch was a terrible suzuki idea thats long since been proven to be bobbins.