dreadycraig Posted July 3, 2009 Posted July 3, 2009 Haven't ridden my bike for about two weeks, tried to start it today and the battery was dead. All the dash lights came on and needles swing round but not enough to turn over the starter motor.got the wife to push me to bump start it (she is well trained ) it ran ok but none of the dash was working, so no lights or speedometer.I gave it a run for 15 mins to my parents, used my dads charger for 1/2hr which gave it enough power for the dash but still had to bump start it, then the dash stopped working again.As there are no electrics when the engine is running, does this mean there is a problem with the alternator? Quote
rosszx9r Posted July 4, 2009 Posted July 4, 2009 Haven't ridden my bike for about two weeks, tried to start it today and the battery was dead. All the dash lights came on and needles swing round but not enough to turn over the starter motor.got the wife to push me to bump start it (she is well trained ) it ran ok but none of the dash was working, so no lights or speedometer.I gave it a run for 15 mins to my parents, used my dads charger for 1/2hr which gave it enough power for the dash but still had to bump start it, then the dash stopped working again.As there are no electrics when the engine is running, does this mean there is a problem with the alternator?bit of an odd one. could just be the alternator is putting the power into recharging the flat battery and not enough to run the dash at the same time. the battery would have to be really flat for that to happen.you need to start at the beginning. charge the battery up fully. this will take a good 12 - 18 hrs. if the bike starts and runs ok then it could be a fault in the charger circuit or a failing battery.my battery is partially failed but so long as i use the bike regularly and keep the charge topped up it's fine. left standing for a couple of weeks and the alarm has it drained so the bike won't start! Quote
Stu Posted July 4, 2009 Posted July 4, 2009 as above you need to get that battery fully charged first then go from there Quote
Pete Posted July 4, 2009 Posted July 4, 2009 I agree, but do bear in mind that now you've totally discharged the battery, or to a state where bumping is necessary (and it sounds like you've done it more than once!) you'll definately need a new battery. This is because once the charge has fully depleated the battery can never be fully charged again and is likely to keep draining quicker. A few months ago I pulled over to make a call, but accidentally left the ignition on (lights off). The call was only for less than 3 minutes and I had to bump it! Bad battery.As it's an intermittent fault it probably won't be your fuses, but it's worth checking them anyway. As everyone's said though just get the battery on charge (if you don't have a charger then buy one or borrow one...not a car charger though) for 12-18 hours and see what happens. Quote
dreadycraig Posted July 4, 2009 Author Posted July 4, 2009 I left the battery on charge all night. It fired up first time and everything worked.Went out for a 70 ish mile ride today with my bro, but he said that when I was indicating my brake light was dimming with the indicator. I think the bike may have been running all the electrics straight off the battery instead of the alternator? Quote
Stu Posted July 4, 2009 Posted July 4, 2009 brake light dimming is a sign of a bad earth or connection check your charge output with a multimeter too Quote
dreadycraig Posted July 16, 2009 Author Posted July 16, 2009 After charging and giving a good ride, I checked the voltage output with a multimeter, it was at about 12V without engine running and 13/14v with the engine running.Went to ride it a week later and the battery had drained again. voltmeter reading was about 6-8v. Is my battery shagged? I can borrow an optimate, is it likely to give my battery a bit more life (i'm skint at the mo) Quote
Pete Posted July 16, 2009 Posted July 16, 2009 Like Stu has said the lights dimming is a sign of a bad earth somewhere along the line. What could have happened is one of your cable sheathings could have dried/perished and let the metal wire touch the frame somewhere, or the cable could have split, or it could just be a dicky/corroded connection somewhere that needs a clean - anything's possible. Best thing to do is to check it all with a multimeter (about £10 if you haven't got one. They sell them at B&Q, Screwfix, etc.) and check for continuity, etc. Once you've found the offending wire it could just be as simple as cleaning it up with a wire brush or taping up with insulating tape. Do make sure that before touching any bare wiring you disconnect the negative lead on the battery (black one) so you don't die.Your battery will be shagged yes. However the fault isn't with your battery, the fault is in the electrics somewhere otherwise your battery wouldn't have died. Your alternator would seem to be fine because it's charging the battery OK and not overcharging. All signs point to a bad earth. The thing about batterys as said before is that once they've lost their juice they will never hold a full charge again and you may find that it drains quicker than it should (i.e. you'll turn the bike off after a 100 mile run, go to start it 5 minutes later and the battery will be dead!). Get a new battery, but find and fix the main fault first. Quote
Colin the Bear Posted July 16, 2009 Posted July 16, 2009 Do make sure that before touching any bare wiring you disconnect the negative lead on the battery (black one) so you don't die Please. How on earth will 12v kill you? Change the battery. The dimming brake light when indicating may just be another symptom of a failing battery. Quote
Guest Posted July 16, 2009 Posted July 16, 2009 SP, we've all put a 9v battery on our tongues, 12v isn't much more, its when its been converted through the coil to HT that its a Shock, thats why when you were young, someone would get you to hold the lead to check if there was a spark, a birght spark would put it on the engine to earth, whereas most of us just yelped as we got shocked..OK, maybe it was just me with the dodgy childhood.. Quote
Pete Posted July 16, 2009 Posted July 16, 2009 I'll leave the battery licking to you hard blokes. Just a thought but if 6 milliamps across the heart is enough to kill someone then surely 15A across the fingers from a bike battery could turn your brain to jam?Just a precautionary measure, but I've always read and been told to disconnect the black/negative connector before doing any electrical work Quote
Guest Posted July 16, 2009 Posted July 16, 2009 Its the amps that kill, not volts... If it has an out put of 100amps then you've gotta worry EDIT: Should mention though, you can't have alot of amps with out alot of volts, you'll be fine....EDIT 2: My grandad survived a 110 odd volt shock by stupidly testing for power with his tongue while working in the U.S, many many years ago.. he's still here!! EDIT 3: Reason for disconnecting is so you dont fry the battery Quote
Pete Posted July 16, 2009 Posted July 16, 2009 Its the amps that kill, not volts... If it has an out put of 100amps then you've gotta worry EDIT: Should mention though, you can't have alot of amps with out alot of volts, you'll be fine....EDIT 2: My grandad survived a 110 odd volt shock by stupidly testing for power with his tongue while working in the U.S, many many years ago.. he's still here!! EDIT 3: Reason for disconnecting is so you dont fry the battery Or make it go bang and get you with the hydrogen gas! Quote
Colin the Bear Posted July 16, 2009 Posted July 16, 2009 The reason for disconnecting the earth is to protect the sensitve electronics and electrics . A slip with a spanner or screwdriver may cause a short circuit. The natural resistance of the body means that a high voltage is needed to pass a current through it. Industrial power tools use a 110 volts supply and are therefore safer. High voltage combined with a high amp output is dangerous. High voltage alone will not kill. Hence the humour of having a stooge hold the high tension cable. 12 volts won't bite. Be a bit of a nightmare riding in the rain if it did. And washing the bike could be a bit twitchy.When messing with high voltage live cables and circuits I was trained to use one hand. It looks a bit casual and some sparks put one hand in their pocket to keep it out of the way. This helps to prevent a short up one arm and down the other and across the heart. A good belt cheers you up no end anyway Quote
dreadycraig Posted July 31, 2009 Author Posted July 31, 2009 Like Stu has said the lights dimming is a sign of a bad earth somewhere along the line. What could have happened is one of your cable sheathings could have dried/perished and let the metal wire touch the frame somewhere, or the cable could have split, or it could just be a dicky/corroded connection somewhere that needs a clean - anything's possible. Best thing to do is to check it all with a multimeter (about £10 if you haven't got one. They sell them at B&Q, Screwfix, etc.) and check for continuity, etc. I've put in a new battery but the lights still dim when the indicators are on, so how do I check the wires with a multimeter? I have done a visual check but couldn't see anything obviously broken/loose etc. Quote
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