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Battery/starter circuit
iiyama - 10/8/07 at 05:40 PM

HOw does this work then? I mean I know how it works, but the battery I have can chuck out 170 cranking amps, (bike engine), the fuse in the loom however is only rated at 30A.

Enlighten me!

David Jenkins - 10/8/07 at 05:47 PM

In a car engine installation, the cable between the battery, solenoid and starter motor doesn't go through a fuse - they're wired directly together using hefty cable. The only bit of the loom involved in starting is the lower-current feed that operates the solenoid when you turn the key to 'start'.

Everything else gets fed via the fuse.

I'd guess that a bike isn't much different.

HTH

David



[Edited on 10/8/07 by David Jenkins]

iiyama - 10/8/07 at 06:04 PM

AH! All clear now Im looking at the Circuit diagram with enlightned eyes!!!!

Cheers!

Peteff - 10/8/07 at 07:18 PM

It doesn't put out all the 170 amps at once or it would be flat straight away. The equipment connected to the battery draws what current it needs from the total and the generator replaces it. The 30amp main fuse on my bike covers the starter as well so you can't do any other damage if you connect the battery wrong.

RazMan - 10/8/07 at 10:33 PM

quote:
Originally posted by Peteff
It doesn't put out all the 170 amps at once or it would be flat straight away. The equipment connected to the battery draws what current it needs from the total and the generator replaces it. The 30amp main fuse on my bike covers the starter as well so you can't do any other damage if you connect the battery wrong.


Pete, the starter won't be fused (as DJ says) only the solenoid. The starter can draw over 150A for several seconds without discharging the battery too much. It is connected directly to the battery and bypasses the fuse box.

[Edited on 10-8-07 by RazMan]

Peteff - 10/8/07 at 11:18 PM

The fuse is built into the solenoid.