Aloha,

Picking up this old thread again!

If I am to put a fuse right after the dyno, where do I put it? In the wire going from “F” or from “D”?

I am also planning on putting a fuse on the + side on the battery, as suggested above.

/Simon

Why do you want to put a fuse in a dynamo wire. It was never done on cars and I have never known it to be done on motorcycles.

As I understood it people above in this thread recommended doing so.
On my Bonneville I have a fuse on one of the alternator wires, as is commonly done.

/Simon

You fuse the generator output because it will generate regardless of weather there is a battery there or not,
So for instance the power wire to the headlamp breaks and shorts out on the headlamp shell, ameter reflector body etc.
The battery fuse would instantly blow but the generator will continue to supply full power . 13A ( if you are lucky ).
This can damage the dynamo if your regulator is not working properly, or simply make the wire hot enough to melt the insulation then go short everywhere.

Now there are not many wires in a M20 loom , but replacing them is a job I do not want to do just because a wire broke.
I have seen an A65 actually catch fire & that was traced back to a short in the power feed to the ammeter.
Seen lots of bike with a total mess of melted wires where fusing the alternator / generator to 90% of it's maximum would have saved the wiring.

British motorcycle manufacturers in their lofty engineering correctness point blank refused to fit a fuse at all till they were forced to then it was just a single on on the battery, no doubt because a short caused a mike to burn in a shed or garage .

Modern motorcycles fit a dozen fuses for good reasons.

Now in the UK where it is still light enough to be seen riding with no lights whatsoever at 10pm in summer, things are a bit different elsewhere like here where it is pitch dark 1 hour after sunset.

email (option): bsansw1@tpg.com.au

I totally agree with you Trevor. Now where is best to put the fuse, F or D? Or does it matter at all?

/Simon

Pickie of the T plug on the battery, All of my bikes are wired likr this so the battery terminals can be painted over with Liquid Electrical Tape so there is no more corrosion & my wires get a full 6 Volts.


This is where I fitted the fuses finally and to date the only time I have gone there is to donate a fuse to a latter model battery ignition bike rider. Sitting where they are no one has ever noticed them. The fuse holders are tie wrapped to an 8" length of steel flat bar that simply drops down into the frame cavity



The fuses are on both power wires, the battery & the A wire from the rectifier.
And being where it is there is only a few inches wire between the fuse & the rectifier.

email (option): bsansw1@tpg.com.au