Blew the main fuse...

Well on the way home from work today my bike started acting up like it was misfiring so I started to baby it. Pull in the clutch to downshift and it dies on me, inspecting it leads to a blown main fuse. Replaced it with the one spare I had and made it about a half mile closer to home and it blows again. Call the old lady to bring the truck so I can haul the bike home. First thing I notice upon close inspection is a loose ground on the battery and the positive to the solenoid is loose on both ends, is this enough to blow the main? My bike vibrates quite a bit more than a stocker so they could have been gradually loosening and just finally lost contact causing the fuse to let go. At any rate, off to the garage to get the torque wrench out and start checking everything.

These bikes have a battery powered ignition, so if your charging system can't keep up with the electrical demand, the engine will act like it's running out of fuel or clogged carbs.

Would the battery cables being loose cause the main fuse to blow?

Possibly, causing a surge. If in doubt,clean the battery and ground connections, and replace the fuses. The glass tubed ones are AGX in size,some auto parts stores and boating supply places can get them for you. Maybe 10,15,20, or 30 amp ratings are what you'll need.

No, loose cables can't possibly blow the fuse. Either bad fuse clips or a shorted wire somewhere.

I am of the mind that loosing ground could blow the main fuse but I don't know for sure.

Mate....not long ago I had exactly the same problem with my 82 KZ1000. Happened out of the blew too, and I couldn't see any immediate reason.

Before I started buying all new stuff, I went right over the wiring system. I cleaned connections, fixed battery cables, made sure earths were all good, and the result - hasn't happened since.

I may have even posted somewhere on the forum about it.

Go right over your wiring and make sure there's good eart contacts and everything is as it should be.

Peter

It is possible that the loose connections caused your problem. Assuming a constant resistance(your bike), if voltage goes up, the amperage will go down, conversly if the voltage drops (loose connection), the amperage will go up(enough to blow a fuse). That kind sir is what is known as ohms law.
Hope this helps, Tom

Not exactly. Ohms law is current=volts devided by resistance I=E/R. More volts for the same load=more current drawn. Less volts= less current drawn. Any bad connection causes less volts, hence less current draw through the fuse, however right at the point of bad connection where the volts drop heat is generated at that point. That is why loose fuse contacts burn the fuse, it's not from more amps being drawn, it's the volt drop at that point. So if you have bad grounds, you may have heat generated right at that point, but less current will be actually flowing though the fuse. Same with loose anything, loose battery cables, bad inline connectors, all the same idea. No way on this green earth it's going to blow a fuse. That is Ohms law.

I stated what I meant wrong,appologies. wattage is expressed in volt amps, ie. Watts equal volts X amps. If you wattage stays the same, like your headlights bulb, or any other load on the motorcycle will, and the voltage flickeres or drops, the amperage WILL go up. I agree that the loose connection will disappate some energy in the form of heat, but to smoke a twenty amp fuse, your gonna cook some connectors.

I don't mean to argue so will remain quiet after this. :laugh: A bulb rated at 50 watts for instance is 50 watts at whatever volts it was designed to run at, watts will always be less the less voltage applied because the bulb can be thought of as a constant load and ohms law again says current = volts devided by resistance. Less volts cause less current, less illumination of the bulb and less watts consumed. The only place I know of where less volts can cause more current draw is on certain motors, where the volts is too low for the motor to run.

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