hi guys

really need some help identifying a problem, bike has just died and has come home on the back of a truck

Bike its a CBR600F '89 - rode to work this morning all fine, gave a quick splutter just before i got there so i turned it onto reserve tank (was about right for the mileage). pulled into work and left the bike for the day.

came back to it, key in ignition, turned on, green light comes on, put choke on and turned the fuel tap onto reserve again. as soon as i touched the starter button it gave a tiny kick then all the lights went off, totally dead. I managed to bump start it after much trying and it would idle but sounded ruff like it was only firing on 2/3 cylinders, wouldnt take any revs or choke at all without starting to die and gave the occasional pop when i tried to rev it, so i'm guessing fueling isnt the problem, the dash and headlights were dimming when the engine missed beats, and the rev counter was fliting between 6000 and 9000 revs the whole time, when turned off it went completely dead again like before

got it lifted home and checked the fuses under the LH front fairing panel, and also the 30amp fuse where the power lead goes to, all fine, also checked the battery with my crude circuit tester (2 bits of wire and a 12v bulb), although i got a bit of a spark when i touched the wire to the terminal it didnt light the bulb up. now i've left the parking light on before and drained the battery, but it would always bump start and run fine after, its been serviced recently and the plugs changed

anyone any ideas??

 

First step, go to an outo parts store and spend the 10 bucks on a multimeter so you can get a proper voltage reading from the battery. Second, check your battery connections for looseness or corrosion. Put more fuel in the bike, and when you get time take the petcock out of the tank and clean the screen on it (just as preventative measure) You say you just changed the plugs, make sure the boots are on the plugs good and tight. start with the basics.

 

many thanks for the reply mate, if i get chance tomorrow I'm gonna strip it all back and have a look, the connections on the battery are sound as are the plug boots, i just dont know why it would die totally, there is literally no power getting thru or back to the battery when its running, soon as you kill the sluttering engine all the lights go out totally. i dont think fuel is the problem, had the fuel tap out and cleaned the screen 6 months or so ago so I dont think its that either

are there any other fuses it could be other than the 30amp under the side pannel, or the row of 10s and a 15 amp under the left handlebar???

 

Check all your wire connectors. you may have a short or an open connection somewhere. My money "was" on you having one or more bad "new" spark plugs, but after reading more into your symptoms, I have to retract that. Clean those battery terminals and tighten them too.

 

Could be a charging issue. Once the voltage drops below a certain point the charging system will not support proper ignition. Try the following:

1. Check the battery voiltage - should be 12.3 volts
2. If the battery is low, jump start it with another battery, leave the jumper battery connected
3. If it runs, measure the voltage at the battery while it is running, should be 13.8 volts.
4. If it is under 13.8 volts while revving at 2 - 3K then you are having a charging system problem.
5. If it doesn't start with the jump then the problem lies elsewhere.

KongBastard

 

Thanks for the advice guys, been meaning to get a multi never for ages, this is probably a good time to invest in one!

Am thinking its a loose wire or a short as it went from having power to absolutely no power as soon as I hit the start button.

 

too dark to work on it today, no lights in the garage yet ;(

can anyone tell me if i can use a car battery to jump the bike, or will that fry my ageing electrics?? I've done it before once with my old aprillia but it seemed dodgy as hell!!

 

It can be done, but I don't recommend it and take no responsibility for any fried stuff. Just remember that most vehicle charging systems provide 14+ volts while the engine is running, and has more amps than a motorcycle battery, running or not. Make sure you don't have the vehicle running!!!

 

Keep the car engine off and boost away. A battery only provides the amperage the bike requires. It won't hurt your bike.

KongBastard

 

okay getting somewhere now, just been out and stripped it back

the wiring connection on the 3 yellow wires that come out of the right hand crankcase (previously removed and replaced with chocolate block as it fried and melted together) had started to melt again, 1 wire relly bad, 1 not so bad and 1 not at all. i believe the wire run to the rectifier (in between the coils)

I rewired them with a bigger chocolate block for the moment

then i jumped it off the missus car, started 1st time and ran perfectly untill i removed the jump leads, then would just about idle but wouldnt rev and the rev counter was all over the place again like before. I tried leaving the leads on for a bit, taking them off and starting it again but all was completelly dead again

so i'm guessing its either the battery or the charging system at fault?? although i still recon there could be a short somewhere cuz it suddenly died when it seemed to have power before, guessing its time to stump up and buy a multimeter............