7.5 Key fuse Blowing out

[Bauerman]

Anecdote: had a fuse in the lighting system blowing. (CB550) couldn't find the fault, so I put in a large fuse to see what would happen. The extra current melted the fine wiring that runs through the handlebars to the control switches. Ouch....swapped out the handlebars with a parts bike. In the end, it was the license plate light socket ffs.....I detest lighting system faults / shorts.

I agree. If these bikes can loose total power over a 7.5 key fob fuse blowing mine won't be in my garage much longer. I've owned probably 30 street bikes and have never had a bike go cold & dark without any warning while underway.

 

[Gregger]

So maybe it be possible to use a 10 amp breaker fuse as a tool for checking.
On the older rIii it feeds the engine management relay so you might pull the relay then install the fuse/breaker fuse to try an get a handle on this problem. I feel that something is shorted out like fuel pump or lights.
Just an idea would would be is to pull theother fuses then put the 7.5 fuse in and if it doesn't blow then start replacing the other fuses one at a time until the 7.5 blows.
When dealing with problems like these the first thing I ask is has anyone been working on it then they say oh yeah good old joe that knows everything was working on the lights about 2 weeks ago.
On the older r3 which may not mean anything the current goes to the management relay then to fan and fuel pump .
Hth herman

Turbo's suggestion is right on. I have used self resetting blade style breakers, rated slightly below the circuit rating, to track down a stubborn grounded or shorted circuit. The breaker will cycle on and off allowing you to troubleshoot the circuit without melting it. I have even used a cheap compass placed over the wire to help track where the grounded circuit is (Did this on longer wiring runs on heavy equipment). When the breaker completes the circuit, before it trips, the compass needle jumps until the compass is placed past the defect. Here is a typical pic of the breakers I have in my tool box. You can get them in various amp ratings and physical sizes. They don't have to be this type.

 

[Journeyman]

I learn new stuff here everyday. Let us know when you get it figured out.

 

[TURBO200R4]

Little story
I usually do not take on jobs like this but when it comes to a friend well!
Buddy had a car that would quit about every block needed new fuse.
So in with a 20 amp breaker fuse and about 2 blocks the engine stopped with ignition on i opened the hood and at the rear of engine sparking wire
(Grounding out) was so easy seen and hear turned out was a peice of cake to fix.
Moral of story is check it in the dark with breaker installed.
Hth herman

 

[wjb]

So, are you telling us that you do your best work in the dark????

 

[TURBO200R4]

So, are you telling us that you do your best work in the dark????

I guess so
Once and a while i just wake up in the early morning hours with the fix for the problem that I am working on

 

[Gregger]

So not only do you work better in the dark, but you think better when you are asleep... That means you are at your worst in broad daylight, awake... Yikes...

 

[TURBO200R4]

So not only do you work better in the dark, but you think better when you are asleep... That means you are at your worst in broad daylight, awake... Yikes...

I definitely just about brain dead about 5 pm but not as bad as joe biden
Lol