GK74A CDI & fuse ID

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GK74A CDI & fuse ID

Post by Mike89F » Wed Apr 06, 2016 11:41 am

Hello everyone :)

I have a 1989 GSX400F GK74A. (its the 600f teapot with the 400r engine)

Been sorting this bike out and can not find anything workshop schematic wise as its a bit of an odd ball bike.

I have replaced with new parts rectifier regulator, starter solenoid and battery. Removed wiring and checked all ok. Coil packs good. Generator stator refurbished by west country windings. multi meter out and all readings correct. New fuel in and Went to start it for the first time in 2 years all fine. let it idle for a while and good.

Then I gave it a touch on the throttle and the main fuse blew. all 4 fuses are 10amp is this correct as I have no reference?
Replaced the 10amp fuse and it blows straight away when you turn the ignition on.

So I have looked everywhere online and have been told the main fuse is 25amp. Tried this and My CDI Unit went up in smoke when I turned the ignition on. So my CDI is fried now.

Anyone know what my fuses should be and What CDI will fit my bike as I can not find the same CDI unit anywhere.

The number for the CDI is 32900-34C10 . From what I have read up on is that the C10 is the region? guess that's Japan then with it being a grey import.

Oh I'm in the UK.

Thanks hope someone can help :)


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Re: GK74A CDI & fuse ID

Post by ventYl » Fri Apr 08, 2016 9:01 am

Being in your situation I would not simply connect another CDI to your wiring. While CDI itself works with quite a low currents I'd expect that you have some kind of short circuit somewhere in your wiring. Attaching another CDI to such wiring could lead to smoke leak again. You probably don't want this to happen.

Try to disassemble the old CDI. Hopefully CDI that old won't be completely filled by rubber so it has it's internals removable. Cutting the sealant along the side on which connectors are placed should allow you to pull whole CDI internals our of casing. Then try to observe what part of CDI was fried. This can help to localize the source of short-circuit. If the part damaged was final stage switching unit then the good news are that these can be replaced fairly easilly if PCB was not damaged too and the fix is fairly cheap. Their damage would make ignition coil primary windings / wiring a suspect.

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