Suzuki GSX400T flat tracker project – electrical problems

Bubblegumhead · L Plate Warrior Joined: 21 Oct 2016 Karma :

Hi All,

I have an '83 GSX400T, which I've been modding into a flat tracker part time over the last year or so. Apart from wanting to do some respraying, it's pretty much done, and is running well.

However, I have some electrical problems, and this has never been a strong point of mine. All the lights have been replaced, as has the battery.

The problems are: -

The tail light (which is LED) comes on but not the brake light. So I'm thinking the rear brake switch is defective, maybe? Or a bad ground somewhere?

The tacho isn't working. I have checked the tacho cable by removing it from the clock and running the bike, and that appears ok.

Please note that the headlight and horn are fine, and it starts up with no problem. The indicators are not flashing, but I think that is due to the power output of the bulbs being too low for the original flasher relay, so have ordered a suitable replacement.

I have been scouring various threads and sites but have not found a definitive answer for either issue.

So, I would appreciate some guidance. I have a multimeter, but have never got to grips with using it properly.

Thanks in advance.

Nobby the Bastard · Harley Gaydar Joined: 16 Aug 2013 Karma :

Aside from the fact that cutting the rear subframe off doesn't a flat-tracker make, don't ask on here about electrics UNLESS you have a multimeter.

You can buy one for about £6.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

Bubblegumhead · L Plate Warrior Joined: 21 Oct 2016 Karma :

I do have a multimeter...

Nobby the Bastard · Harley Gaydar Joined: 16 Aug 2013 Karma :

Bubblegumhead · L Plate Warrior Joined: 21 Oct 2016 Karma :

Right... checked the switch and continuity to all wires leading to the light and all ok. So had a closer look at the light... turns out one of the wires had broken off the circuit board. So after a bit of hassle with soldering, have managed to sort it.

I would still appreciate some constructive advice on how to check the tachometer.

Nobby the Bastard · Harley Gaydar Joined: 16 Aug 2013 Karma :

Assuming that the tacho is run off the gearbox (which would be weird for a modern bike, my 26 year old exup is competely electrical) if the cable is turning and has a good square shape to it, the clock is broken.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050