Weak battery and starting on Seca 550

I admit I'm chomping at the bit to get out and ride, it's been a really long winter here in the north east. I spent the winter swapping a battery tender between the bikes and decided last week to get them running and ready for the season. Like some others here, I've been putting off some necessary work (fork seals) on my 82 Seca 550. With the battery tender indicating that the battery of the Seca fully charged, I tried to start her up with no success. The starter turns but she will not fire- and the battery does seem to drain down swiftly when trying to start. So I go thru my checklist: good spark, clean air filter, stabilized fuel flowing but she still won't fire. I ended up bump starting her then riding about a mile and now she's starting fine by pressing the starter. My question is, will a tired battery allow the starter to spin but not provide enough juice to actually start the bike? I think I recall reading somewhere that at a certain voltage the starter will crank but the engine won't fire. With a foot of snow on the ground and sand all over the road, I'm a month away from any riding and I wonder if I'll have the same trouble when riding season arrives. A new battery might be in order.

Please let me know what you think.

JB

 

Sounds iffy to me; more likely it was spinning, just not fast enough for the engine to catch. If a battery has enough juice to turn an entire engine, it has enough to power a coil.

 

NOT!! The battery can turn the engine over when low, but you need a good strong battery to fire it up.

 

+1 on what hog said.

 

I think I read somewhere that the TCI needs a minimum of 9.8VDC in order to throw a spark. If the battery drops to under that voltage during startup, it will spin yet not spark. Or was it that the spark was too weak to ignite the air/fuel mix.


I would test the battery voltage drop when starting the bike. It may tell you the condition of your battery or the condition of your starter brushes.

 

I don't think it'll throw a strong enough one at that.....well, it might once, if you're lucky --- and the bike is still a bit warm. If its cold, SOL

 

I had this yesterday. Hadn't run in 6 months, and it's been pretty cold since. Really low compression (all about 25psi), drained my spare battery. Hooked up the other battery, took a couple tries but she slowly starting popping, then firing, and smoking like crazy. Now her compression numbers are all good, and she starts no problem. Maybe there was just no oil in the rings.

 

Not that it's necessarily your problem, but I learned something recently and wanted to throw it where others might see it.

My wife's '83 750 Shadow has always been hard to start cold. If it sat for a few days without a charger on it there was no starting it without a boost box. It always restarted fine. She chewed up a couple batteries and I cleaned every electrical connection I could find. Finally, with an AGM battery it got to where it had a decent chance starting after sitting.

We recently put it up for sale. Of course the day the first buyer was to look at it the starter gave out. Two of the brushes were completely gone and it had been running on the ends of the brush wires, there was a rut in the commutator from that. After turning the commutator and sticking new brushes in it it fires up cold before you can even completely depress the switch.

Those shot brushes were pulling so much current it was dicey whether there was enough voltage left to work the ignition.

 

Thanks all for the input. We'll see how things go after sitting for another week. Lucky for me my house sits on a small hill making bump starts easy...