I was riding my 99' CBR900RR for the first time this season.

I kept sputtering while I rode it...it'd only do it occasionally. The RPMs would drop to zero for a second, I'd lose power, then it'd kick back on.

Then I was cruising along, and it just died. RPMs dropped to nothing. I put it in neutral, and hit the start switch...nothing happens. The lights turn off when I hit the start switch, just like they should, but the bike doesn't crank.

Kill switch?
Starter relay?

How do I diagnose this.

-Richard-

 

Replaced the kill switch.
Still no crank.
Realized the starter relay wasn't clicking.
Replaced the starter relay.

Still no crank.

30amp main fuse isn't blown.
Main feed wires properly attached to the relay.
If I run a jumper from the BAT+, directly to the starter, it cranks
If I run a jumper from the BAT+, to the red/yellow wire on the relay, it cranks

Press start button, nothing happens.

Yes, it's on run.
Yes, the key is on the "ON" position.

 

You checked the battery voltage right? With a voltmeter and not with a charger, I mean

 

sounds like your ign. wire to your key might be loose broke or if it has a fuse blown fuse. but acting up DURING the ride then dying ide check the wire.

 

Battery voltage is fine, ~12.5v. I've been keeping it on the charger, because I keep having to turn the key on, which turns the lights on, which drains the crap out of the battery.

Ignition fuse is fine. I replaced it anyways, still no crank.

All of the fuses share power from the key, and I've still got headlights, and such.

I unplugged the start/kill switch. Ran a jumper from the battery, to the plug where the start/kill switch plugs into everything. Red/yellow wire, and it cranked from there. So it's happening AT the "new" start/kill switch, or before it.

Tracing diagrams sucks ***.

 

then check the wire leading up to the kill switch. like i said it sounds like a bad wire since it didnt just stop. im pretty sure its something that was grounding out then fried.

 

Fixed!

Turn out to be a bad solder. One of the wires that hooks to the killswitch contacts decided to break.

1/2" piece of wire, some lead-rosin solder, and a soldering pencil, and I was in business!

Now I've got other problems to deal with...my front brake is spongy, and is dragging BAD.