15A headlight fuse gets really, really hot, why???

[tony2001]

Hello people.
My stock 86 FZR 400 is experiencing some weirdness, the 15A headlight fuse gets really really hot while running the bike. I've checked the wiring, the fuse, the fuse box, the battery, the V.R, everything seems fine, but it still gets burning hot. I havent upgraded the lighting, or changed to higher voltage bulbs, everything is stock.

Is this normal, does anyone else experience this, is there a fix, a friend advised me to change out the oem fuse box for something more heavy duty.

All responses greatly appreciated

[the_finch]

On my 1997 FZR600 (which uses the dame headlight assembly) my fuse block has a 20amp fuse in it. I'm 99.9% sure that you have a little too small of a fuse in there. I'll let someone else chime in too, though.

[trifgeorge]

yup. there should be a 20 A fuse. replace it and see how it behaves.

[yamaha_george]

yup. there should be a 20 A fuse. replace it and see how it behaves.

Hi,
There is a wiring diagram for the FZR on the WIKI with fuses & ratings .........................

[tony2001]

Hey George wassup

According to the manual and the actual fuse box listing its telling me 15A, the advice of the board is 20A. Reading old posts on this, others are stating clean the fuse box with some electrical spray cause the connections might be corroded or to check the light switch button for frayed connections or wiring.

I will try all of these suggestions and hopefully it will pan out

[yamaha_george]

Hey George wassup

According to the manual and the actual fuse box listing its telling me 15A, the advice of the board is 20A. Reading old posts on this, others are stating clean the fuse box with some electrical spray cause the connections might be corroded or to check the light switch button for frayed connections or wiring.

I will try all of these suggestions and hopefully it will pan out

Tony
Glad you checked out the real info 20 Amp could burn the harness,
The switch is always a strong suspect . The fact it is pulling slightly high current leading to heating make me suspect a slight connection to ground, you may want to clean any connector that has a ground wire & the possibility of a "trapped / pinched wire to ground through rust.
I had that near the gas tank .

Good to hear you active on the board, stay with us they are a good bunch

[haro504]

i agree withe the corroded connectors had it happen to me with autos it was bulb sockets

[the_finch]

Hey George wassup

According to the manual and the actual fuse box listing its telling me 15A, the advice of the board is 20A. Reading old posts on this, others are stating clean the fuse box with some electrical spray cause the connections might be corroded or to check the light switch button for frayed connections or wiring.

I will try all of these suggestions and hopefully it will pan out

Tony
Glad you checked out the real info 20 Amp could burn the harness,
The switch is always a strong suspect . The fact it is pulling slightly high current leading to heating make me suspect a slight connection to ground, you may want to clean any connector that has a ground wire & the possibility of a "trapped / pinched wire to ground through rust.
I had that near the gas tank .

Good to hear you active on the board, stay with us they are a good bunch

Leave it to me to give bad advice. Sorry.

Do what George said and it should be fixed.

[tony2001]

*****Update*******

Ok, according to my original Yamaha FZR 400 hardcopy manual and the wiki here, it's a 10A that goes there, for some reason my fuse box lid was telling me 15A and thats what I was going by. Maybe somewhere along the line there was an unintentional switch on the fusebox lids, probably from the time it was at Speedwerks, that guy has a ton of FZR 400 parts.

Anyhow, I cleaned the connections with PJ heavy duty electrical spray and replaced the 10A fuse, ran it for a lil bit, checked the fuse, minimal heat in that particular area. Hope it stays that way, Thank You once again everyone