Topic: Yet another Fuse thread : AGX or AGW

[amitr0]

I have a '76 Honda CB550KFour, and I am having fuse heating issues. I read the other threads here, and I will start debugging it soon, but for the time being I need to buy fuses for it (bike died away from home), and I am unsure which size works best, here in America we have the AGW or the AGX, and none of the manuals or the threads mention which one, all discussions, as far as I can tell, were about correct amperage.

https://www.littelfuse.com/~/media/automotive/datasheets/fuses/automotive-aftermarket/glass-fuses/littelfuse_aftermarket_glass.pdf

Can anyone comment?

[bryanj]

Get the hondaman blade fuse conversion

[Alan F.]

If the glass fuse is heating up, replacing it with another glass fuse isn't the solution.

*Disconnect your negative battery terminal.
*Dismount your fuse box.
*Clip the wires from the offending fuse holder.
*Strip the ends of the wires about 5/16"
*Add an ATC/ATO fuse block, every Auto parts store and Wal-Mart (in car stereo area) has these, if the wire is looped like this cut it in the middle and strip the ends 5/16". Some arrive with the ends already stripped, twist the strands of wire together to keep them neat and compact before placing them into crimp connectors.


*Connect the wires with "Insulated Butt Connectors - 16-14 AWG (for 14 gauge wire) these have a small metal tube inside, the stripped, twisted wire end goes in but only the bare part of the wire goes into the metal tube inside to be crimped which makes a solid electrical connection.


*Crimp the connectors with the correct tool, regular pliers don't work very well and these are inexpensive:

This one is from home depot and comes with the connectors you need, Harbor Freight has one too, Auto parts stores may also.
Use the spot at the tip marked with the blue dot to crimp blue connectors.
Finished crimped connections should look like this:


*Then just add the correct amperage ATC or ATO automotive fuse, you can get them almost anywhere, ask at the counter.

*Don't forget to mount your bikes old fuse holder back in its place.
*Put your side cover back on.
*Keep all of this stuff with you when you ride.

Good luck and get home safely.

Edit: *reconnect your negative battery terminal before trying to start your bike, you've already had a bad day.

[Deltarider]

I've had success in just cleaning the stock fuseholder.

[david 750f]

As Delta says clean the fusebox connectors first (its a free potential fix). You want the 25mm long fuses, shown as AGX on your chart. Honda dealers still carry the fuses and they are only $1.00 each.

[Deltarider]

Another reason I prefer the stock fuse box is, it will enable - when needed - me to measure amps. Just flip the fuse out and connect an ammeter that can handle 10A (better: 15A) to the clamps.

[amitr0]

Another reason I prefer the stock fuse box is, it will enable - when needed - me to measure amps. Just flip the fuse out and connect an ammeter that can handle 10A (better: 15A) to the clamps.

are those AGX or AGW? No one answered that question

[amitr0]

If the glass fuse is heating up, replacing it with another glass fuse isn't the solution.

*Disconnect your negative battery terminal.
*Dismount your fuse box.
*Clip the wires from the offending fuse holder.
*Strip the ends of the wires about 5/16"
*Add an ATC/ATO fuse block, every Auto parts store and Wal-Mart (in car stereo area) has these, if the wire is looped like this cut it in the middle and strip the ends 5/16". Some arrive with the ends already stripped, twist the strands of wire together to keep them neat and compact before placing them into crimp connectors.


*Connect the wires with "Insulated Butt Connectors - 16-14 AWG (for 14 gauge wire) these have a small metal tube inside, the stripped, twisted wire end goes in but only the bare part of the wire goes into the metal tube inside to be crimped which makes a solid electrical connection.


*Crimp the connectors with the correct tool, regular pliers don't work very well and these are inexpensive:

This one is from home depot and comes with the connectors you need, Harbor Freight has one too, Auto parts stores may also.
Use the spot at the tip marked with the blue dot to crimp blue connectors.
Finished crimped connections should look like this:


*Then just add the correct amperage ATC or ATO automotive fuse, you can get them almost anywhere, ask at the counter.

*Don't forget to mount your bikes old fuse holder back in its place.
*Put your side cover back on.
*Keep all of this stuff with you when you ride.

Good luck and get home safely.

Edit: *reconnect your negative battery terminal before trying to start your bike, you've already had a bad day.

Thank you, well that is for the future. If you read my post, I said I was going to debug it.  In the interim, wanted to know what fuse gets the bike back home.

If it is a heating issue, it could be a bad wire anywhere, and in that case, will a fuse box upgrade help?

[TwoTired]

AGW fuses are 7/8" in length.
AGX fuses are 1 inch in length.
AGC fuses are 1 1/4 inch in length.

My 76 CB 550F uses AGC fuses.  Earlier bikes used the AGX style.  I'm not certain exactly when the changeover ocurred in production.  Likely when the ran out of earlier style.

Check your fuse holder. You select the fuse where the end caps will make the maximum contact with the fuse clips.  The less contact surface, the higher the possible resistance contribution.  And when current flows through resistance, heating occurs.

If your fuse is melting near the end caps, fuse clip heating and/or the solder connections on the back are likely causes.  If the clip holder plastic is melted, then the clips can't "float" in the holder to align with maximum contact on replacement fuses.  The clips can also tarnish, sometimes with a transparent coating which also contributes to higher than desired resistance and heating.

The stock bike generally draws about 10 amps through the 15 A fuse.  This warms the internal fuse link, but does not melt it.  You can hold your thumb on it to feel it's warmth.  If it burns or blisters your thumb, you are either are drawing more current through the fuse than stock configuration, or you have a fuse block issue.  "Blowing" fuses that melt near the end caps are almost certainly a sign the fuse clips need polishing or solder starvation on the back side of the holder.  Over current fuses blow near the center of the link.

I am still using original refurbished fuse holders in all my bikes.  They work fine if attended to properly.  I've only had to replace one of the stock ones, because the holder had melted too badly prior to my ownership, and prevented the clips from grabbing the fuse with proper alignment.

The last bit about the clips is contact tension.  You should need a tool to remove a fuse.  The clip tension should require that.  If you can remove it with your fingers, the clips need tensioning.  They can become brittle with heating.  So, sometimes bending them to improve their grabbing tension can snap them.  Low contact pressure on the fuse end caps also can contribute to added resistance heating.

These are simple to maintain devices.  But, they do demand infrequent attention.

Cheers,

[Stev-o]

*Connect the wires with "Insulated Butt Connectors - 16-14 AWG (for 14 gauge wire)

Hey Alan....I'm sure butt connectors will work but I've never trusted them for a permanent connection.
I prefer soldering the wires together and covering with shrink wrap

[RAFster122s]

*Connect the wires with "Insulated Butt Connectors - 16-14 AWG (for 14 gauge wire)

Hey Alan....I'm sure butt connectors will work but I've never trusted them for a permanent connection.
I prefer soldering the wires together and covering with shrink wrap

+1

[Alan F.]

Stev-o & RAFster122s you're both right it's not a trustworthy permanent repair.

In my mind at the time having just woken up and checked the forums for a thought to help wake my mind up until coffee was ready. I was replying at 5am to an issue posted after 11pm where the bike died away from home as stated by the OP. It was easy to imagine someone sleeping in a Motel 6 with a busted bike parked outside, hoping to fix it in the morning with tools and parts bought within walking distance.

I know that I could do a much better repair myself, or even install a Hondaman fusebox, but out on the road I'm thinking of the best repair that'll get the bike and rider home under their own power without adding to the hassle.