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Discussion Starter · #1 ·
Is that too low? Will a day or so on a battery-tender get it back in shape? What's the bottom end? Bikey no start. Is this amperage insufficient? I'm also investigating starter solenoid.

Thanks

Gregor
 

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Discussion Starter · #3 ·
Went to Schuck's and had them load-test it.

Voltage when hit starter button? Don't know; is that on your gauges? I have a 2000, it's not on mine.
 

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GregorMac said:
Don't know; is that on your gauges?
No, I was figuring you had a volt meeter, which is why I asked about the load test.

Was the batt at 11.8 under load or after the test was over.
Assuming it was a 11.8 during the load & the test was done properly, then the batt is good.

Not sure about bikes but most cars will still crank over until about 10 volts.
 

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GregorMac said:
Is that too low? Will a day or so on a battery-tender get it back in shape? What's the bottom end? Bikey no start. Is this amperage insufficient? I'm also investigating starter solenoid.
I'm not too sure exactly what that "load test" was measuring, but if it was cold cranking amps, it's _way_ low - the battery for my '99 M750 is a Yuasa YT12B and it's specs say it ought to put out 125 Amps...


big
 

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A load tester measures the available voltage under a load.

I read it as 11.86 VOLTS as in under load your bat drops from 12.4 down to 11.86 VOLTS

GregorMac, is the bike cranking slowly or is there no power at all?
 

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Mdriver is correct. A load test would be applying a load of 3X the amp hour rating of the battery for 15 seconds, eg. with a 10 AH you would be drawing 30 amps for 15 seconds. The voltage should stay above 9.6 volts. The battery must be fully charged to do this test. If your battery read 11.86 volts it is good
 

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Discussion Starter · #9 ·
Mdriver said:
A load tester measures the available voltage under a load.

I read it as 11.86 VOLTS as in under load your bat drops from 12.4 down to 11.86 VOLTS

GregorMac, is the bike cranking slowly or is there no power at all?
Well, the dude at Schuck's said 'amps', and I'm not Einstein when it comes to bike electrics. The bike isn't starting; that's my problem. Knowing the battery is good, now has me looking at the starter solenoid. hmmm...I saw in one thread where someone said to use a piece of heavy-gauge wire across the leads of the solenoid. How heavy?
 

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GregorMac said:
Well, the dude at Schuck's said 'amps', and I'm not Einstein when it comes to bike electrics. The bike isn't starting; that's my problem. Knowing the battery is good, now has me looking at the starter solenoid. hmmm...I saw in one thread where someone said to use a piece of heavy-gauge wire across the leads of the solenoid. How heavy?
4 or 6 gauge. same as the battery leads. A screwdriver works.
 

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Discussion Starter · #12 ·
Just tried the screwdriver thing...no go. Tries to turn over. I put the battery on the tender and we'll see what happens tomorrow. Thanks for all the help, guys.
 

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If it tries to turn over, it could be the battery still or a starter going bad. Someone said before you could replace the internals of a starter with those of some Yamaha sportbike. Not sure which but someone here knows. It's much cheaper than the stock Duc equipment...
 

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Assuming the battery is good your next step would be to apply battery power directly to the starter. If it still doesn't crank you have one of the following:

dirty connection at the starter lug
bad starter
bad engine

That is assuming your battery and connections are good. A quick check would be jump your bike from a known good battery.

A more professional way to trouble shoot the problem is to look for voltage drop, which is the voltage consumed at each point of resistance. You would place the voltmeter in parallel with the connection or suspect item and crank the starter. 0 V is perfect. General any car spec is .2 V/connection, wire or switch, .5V for the whole circuit. Expect higher numbers on the wires on a bike.



____ +
l l---------------------------__
l V l - l__l Solenoid
l___ l---------------------------

Polarity is positive towards battery, but no big deal, the meter will just read in reverse.

Sorry about the bad drawing. Maybe someone can do a good one.


Oh, forgot. If you need to clean the connection at the starter lug be careful, it breaks easily.
 

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Discussion Starter · #15 ·
So, my plan is: try to jump the solenoid which, I think, is what howie is saying in "apply power direct to starter." If that doesn't work, clean starter lug, and try again. My hope is that it is a starter solenoid and I can give Chris @ CCW some of my money. [thumbsup]
 

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Discussion Starter · #17 ·
Mdriver said:
Keep in mind, if the bike starts when jumping between the 2 terminals on the starter solenoid doesn't prove that the solenoid is bad. It just proves that the starter and the battery are good.
Hmm...good point. However, what else is in line to F things up? Obviously dirty connections. Anything else?
 

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NAKID said:
A short in the lines from the solenoid to the starter could be a problem...
Possible, but unlikely, a short there would generate quite a lot of smoke - the recommended batteries will dump well over 100A into a dead short - you'd know about _that_ soon enough... More likely would be a bad connection at either the bolt on terminal of the solenoid or at the starter... It's also possibly the brushes or commutator in the starter, but again, unlikely - I've got 110k miles on mine and it's still got the original brushes in it - unless you've got high mileage and do lots of very short trips (implying many more starts than usual) I doubt it'd be that.

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i would look at the plug at the starter. i have seen alot of lovely growth there, and it hinders voltage. your battery test sounds fine, that was a volatge reading of 11.86, the battery sounds ok. i checked mine with a voltmeter. at rest nothing on, leads on battery, 13.0 volts, ignition on 12.0, hit the cranking button, slow turns and 11.0 to 10.0 to 9.0 etc. pulled the boot from the wire to the starter, wonderful green goo. the factory tried to some grease in there, but not enough. cleaned with wire brush and as much dielectric grease as the boot would hold, voila! 11.9 while cranking at the battery. if that is what you find you may also want to hit all the connectors on the chassis with the same grease. very interesting what you will find inside those connectors, especially if you ride in the rain.
 
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