OK, in my other thread I thought I might need a new alternator but it seemed to be a ground issue. I took the whole bike apart and used Detoxit on all the the grounds and connections, then put dielectric grease on them all and reconnected them. I replaced the alternator with a newer 50 amp unit from a newer k bike. I left the battery disconnected all night, It read 12.55 volts at night then this morning tested again, same reading 12.55 volts.

I get her back together and attach everything cleaned and reconnected, battery volts level 12.55 volts.

So I try to start her and it is like I have a dead battery, barely turns over then nothing. I then jump the bike with cables from my car and it starts right up, battery reads 13.95 volts. When I throttle up I hear a weird thump or metallic sound coming from the starter area. Looking over other threads I think I may have fried either the starter relay or starter previously and it may be constant on?

Anyone with opinions, I don't want to replace parts I don't need, How do I test which one it might be?

Have you ever taken the starter motor out of the bike and disassembled it? Odd things occur when the carbon brushes have a few K's (err, miles) on them and they dust up the guts of the starter motor. Clean it out with contact cleaner or brake parts cleaner, measure the brushes for length and carefully reassemble then fit it back into the bike. See if that does anything. It's an easy job and there are several posts on how it works and how to take it apart right here on the forum. Have you ever noted turn indicator lights flashing irregularly or the headlight not always working? That's a telltale sign your bike suffers this fairly common ailment. I hope I'm not steering you in the wrong direction but it's worth a go.

Let us know. Good luck.

BTW, be careful 'jumping' the bike from a car with the car's engine running. A static battery jump is best. That expensive ECU can be tender.

Get the battery tested on a high load test because what you are saying is consistent with the battery having a bad connection internaly. By that I mean that there may be a connector from one cell to the next that is cracked through but still touching so the battery takes a charge, retains the charge because there is nothing wrong with the cells but it can't deliver the current necessary to turn the starter under load. When you connect the car battery all is ok so there is no problem with all the other components.
A qiuck check is when you press the starter button all the lights will go out not just get dim and then will come back on but sometimes a bit slowly not immediately but take like about 1 to 1.5 seconds to get full brightness.

You need to test the voltage under load, the fact that you know it is 12.55 volts says you used a digital meter which is fine, but they draw two thirds of five eigths of nothing as far as current draw whilst they measure. So get a high current load test done and measure the voltage then whilst it is under load, my guess is it will be way lower.

Second point you should not use dielectric grease after DeoxIT or indeed ever use it on electrical connections and that goes doubly for switches. If you have a high corrosion risk due to damp and bikes would fit that profile DeoxIT Shield is the correct stuff to use as a follow up after the the DeoxIT cleaner.
Regards,
K-BIKE

+1 on the DeoxIT Shield.

check the starter relay i head ....from what ive read here it seems a pretty common occurence ...especialy on low volts durring cranking ....i dont believe thay are hard to disassemble and you could use a points file to clean up the contacts.

but i would certainly be cleaning up the starter motor first ...

i recently bought a new set of brushes (which comes with the backing plate on the earth side ) and it wasnt expensive at all .

i guess for a reasonable load test ....you could turn on the lights on high beam .
i guess thats only about 5 or 6 amps ....but would cetainly give you a good idea....i would expect the voltage to drop slowly if the battery was in reasonable condition ....

deoxit and the sheild are excelent ......good reminder k-bike

good luck

OK here is the update. The noise I heard when I jumped it was my fault. When I replaced the alternator with the new 50 amp, I didi not take the rubber spacers out of the end of the old alternator and out them in the new one. Problem fixed.

I did take the starter relay out and puled it apart and cleaned the points. Works fine.

I tried a sort of bench high load test. I put on the high beam as K-bike suggested and turned everything on and tried to start it. The light did not go out or dim but the voltage fell to 10 volts. When I jumped the bike with my car(not running), the bike fired right up no problems.

I think it is the battery, even though it reads 12.5 volts at rest and when running with the new alternator it reads 13.95 volts. It seems to be the problem, the fact that the bike starts when jumped tells me it is not the starter.

I am going to leave it on the charger all night and try it in the morning. If it wont start then I can be more certain that it is the battery.

what i meant by a load test was to just turn on the lights and monitor the voltage at the battery .

but it certainly sounds like you have at least one weak cell in the battery ...if so i would expect the battery to read 10.5 volts within about 5 minutes with the lights on .

Thanks charlie 99, I will check it tomorrow.

lhead71 wrote:I tried a sort of bench high load test. I put on the high beam as K-bike suggested and turned everything on and tried to start it. The light did not go out or dim but the voltage fell to 10 volts. When I jumped the bike with my car(not running), the bike fired right up no problems.

If your light don`t go out when trying to start, your load shedding relay doesn`t function as it should.
The coil to the l.s. relay is grounded at the starter via the starter relay output, a short in this circuit
(with an [almost] burnt of wire at the point shorted) could be the reason of your problem...........
and when jump starting you get that more juice that it masking it.

On the other hand:
a) All connections is in the relay box, not much can happen there (unless PO have done a lot of fiddlin`).
b) With a heavy short like that you would have noticed that your relay box have started smoking and
soon getting serious cancer.
c) When taking out the starter relay you would have noticed some serious melted wirer(s)/insulation.

Last possibility is that PO have cut the wire to the l.s. relay coil, and grounded it permanently.

Inge K.

Further please note that the 14 Volt measured with the bike running is a function from the alternator and not the battery. What you see is what the alternator delivers. Have a good look at Bert's electric diagrams, they're very helpful with tracking wires/finding issues.

OK, I think I have it narrowed down. I am almost positive it is the battery. I let it charge all night into Monday, when I disconnected it from the charger It fired right up, shut it down and let it sit overnight without the charger attached.

Today, I went out to start it in the morning and all the lights come on but no start, would not even turn over. I guess it is time to bite the bullet and buy a new battery, even though the old one is less than a year old.

Bought a new sealed battery, measured voltage right out of the box 12.79. Put it in the bike, let it sit for 8 hours connected to the bike, remeasured voltage 12.68, pressed starter fired right up. I guess it really was the battery after all.

Thanks everyone for your time and suggestions.

I replace the battery with sealed battery 45 AH.

It never lets me down on starting.

Battery should have a guarentee

Got up this morning after letting the bike sit for two days with a new battery, and not only did she start, she purrs! I replaced the cracked vacuum caps and crankcase breather hose, air filter, tightened all connections, Deoxit'ed all connections, replaced the alternator with a 50amp unit, and put all new fuses in her.
Thanks guys for all your suggestions and help, very happy man today! Rode to work and enjoyed the heck out of the ride.

rev it up and head for the hills

yay ..!!!! great news lhead

Nice work !

Lots of pro and cons about dielectric grease on electrical terminals,lots of saltwater boat guys use it on everything but it will not help make a good electrical connection it fact it's a insulator, it will keep them from corroding and keep the soft rubber seals pliable and help keep the connection water proof.