electronic ignition question??

hey everyone... i have a weird question.

i'm building a rigid kz-900 chop of sorts that is kind of like the bastard child of a boardtrack racer with a hot ass motor in it and a old-style rigid with a skinny tire.

now, i basically fabbed the frame and cannibalized the front end off a later model bike, i've got it rolling, the motor mounts are clean, everything is lined up except for the electrics and a few of the controls. (no big cheese, right? riiiiight! hahahaha) so i'm switching to an electronic ignition. the unit i have is MSC or something of the sort. now i'd like to shave as much weight as possible, hence i've eliminated the starter and am going to go with kicker-only on this one. i have a battery eliminator but i really don't know if it'll work with an electronic ignition. from what i gather i need a little bit of charge to get it to fire initially.

what do you guys think? any advice/ideas would be appereciated. thanks!

-selrahc

a best guess is that unless you have a small battery with a guaranteed 12V supply to the ignition unit, the bugger is probably not going to start, I do not have any knowledge of how a battery eliminator works or whether it will supply a smooth enough supply to the ignition to function once the machine is running.

any takers with a bit more know how on this one......?

I've done it with no problem, but I had to bumpstart since it didn't have a kick.

I had a KZ550 with no battery using a 5600 uFd /50-volt capacitor and the stock Kawasaki electronic ignition. It could bumpstart instantly with just two or three steps walking. You need the capacitor in place of the battery to smooth out the voltage pulses.

The Kaw ignition is best for this type setup because it wastes the least amount of electrical energy when starting. I don't know if a MSD ignition (if that's what you meant) will work without a battery because it has to pre-charge a capacitor.

You'll want to have a battery, at first, to get it tuned right. You need it to start on the first or second kick reliably every time before going batteryless. Going batteryless works, but you're carbs, valves, and timing better be right on or it may be tougher to start.

Oh, and this will only work on bikes using a permanent-magnet alternator. That means it won't work on a 77 650, earlier 400s, and earlier 750 twins. If your alternator cover has three phillips screws in the middle in a triangle formation, it's not a permanent-magnet.

Post edited by: loudhvx, at: 2006/11/28 12:26

Hey loudhvx do you have a diagram on how you did it and what does 5600 uFd /50-volt capacitor looks like .

It's very simple. You just replace the battery with the capacitor. The capacitor has a positive terminal and a negative terminal like a battery. It's about the size of two 35mm film canisters stacked. The screw terminals will be smaller than those on the battery so you'll have to do some wire splicing. The wires also don't need to be as big as the battery cables. 12 gauge or 14 gauge should be fine. You can probably use anything from 5000 uF to 12,000 uf (that's micro-farad), but the higher the voltage the better. 35v would be the minimum I would recommend.

They'll look something like this (you only need one of the canisters):



Sprague/Vishay is a good brand.
You can get them or similar ones from MCM/Newark or Mouser.

Post edited by: loudhvx, at: 2006/12/09 01:48

So if you have a real good tuned engine with a kick start you can replace the battery with one of those caps cool.