Topic: Starter draw kills battery quickly

[incredibull]

Can't seem to figure this one out. So far I've pulled, spray cleaned and brushed where needed, and reassembled just about every single electrical connector with dielectric grease. I've also replaced the battery. Even still, I can't seem to get more than ten 2-3 second cranks out of the battery before the starter just kills it dead in its tracks, requiring me to throw it back on the charger. Both the old (newish) and new batteries hold a solid 12-13v after charge and drop very little below the 11.5 mark once the starter refuses to turn.

Note: the bike is NOT being ridden at this point, as I'm still getting it back into riding shape. While I haven't verified that the battery is being charged while running, I'm not running the bike anywhere near enough to drain the battery.

There was very little corrosion in any of the electrical connectors or wires. This is not a rust belt bike. Haven't measured resistance through the positive lead, but ground to engine nets nearly zero resistance.

Does the starter really pull this much load? Would it be worth it to pull the starter and disassemble/clean?

[Spanner 1]

Your last sentence answers the question, yes, take the starter out and check/lube it ...search the FAQ's

[TwoTired]

The stater solenoid just passes power to the starter.  It draws very little power itself.  The stater motor usually draws about 120 Amps.  However, if the armature bearings are worn enough to allow the armature to hit the starter motor frame, it is equivalent to connecting the two battery posts together, which will drain a battery is pretty short order by drawing far more amps than 120.

[Philly550K1]

Note: the bike is NOT being ridden at this point, as I'm still getting it back into riding shape. While I haven't verified that the battery is being charged while running, I'm not running the bike anywhere near enough to drain the battery.

<scratching head> why not put a voltmeter on the battery while it is running to see what voltage at what rpm you get? as to the last part, are you just running it at idle or thereabouts? ten starts plus X amount of idling will uncharge a battery to below-starter-turning juice. heck, riding it in city traffic will do that....

what bike?

-jc

[MJL]

Note: the bike is NOT being ridden at this point, as I'm still getting it back into riding shape. While I haven't verified that the battery is being charged while running, I'm not running the bike anywhere near enough to drain the battery.

<scratching head> why not put a voltmeter on the battery while it is running to see what voltage at what rpm you get? as to the last part, are you just running it at idle or thereabouts? ten starts plus X amount of idling will uncharge a battery to below-starter-turning juice. heck, riding it in city traffic will do that....

what bike?

-jc

+1.  Most of these bikes have alternators that have to be above X rpm before they charge. IIRC the 650 has to be over 1600 rpm in order to charge.

[mystic_1]

So, you're just starting it, running it on the stand for a while, then shutting it off?  Yeah, that'll drain your battery pretty good.  As said above you don't get charging current until above idle, and really it takes sustained rides to recharge the battery properly.  Making lots of little 2 minute hops around the block won't do it either, need a good 10-20 minute ride.

mystic_1

[incredibull]

So, you're just starting it, running it on the stand for a while, then shutting it off?  Yeah, that'll drain your battery pretty good.  As said above you don't get charging current until above idle, and really it takes sustained rides to recharge the battery properly.  Making lots of little 2 minute hops around the block won't do it either, need a good 10-20 minute ride.

mystic_1

OK let me clear up a couple of things. I haven't been running it all that much because I haven't cleared up a tank leak issue, and it's still a hard start at times. So, the few times that I've started it (I can count them on one hand) I've put the battery back on the charger afterwards.

On a new battery, even after a full 12-hour 2A charge, the starter can drain the battery very quickly as described.

why not put a voltmeter on the battery while it is running to see what voltage at what rpm you get?

I am going to do exactly this the next time I get the bike started and run above the charging RPM. The bike sat for several years and is still very finicky about starting. I'm getting it all tuned up at this point, but this is my first bike and I'm learning as I go along here.

It's an 82 650

[Spanner 1]

I've seen starter motors that sat for some time have 'soft' brushes and deposit their carbon around the commutator so that the sections on the comm. are shorted-out by the deposits and the starter motor draws a big amount of amps because of this.....might be it....easily fixed by a good clean....