Not starting after gassing up

[drsib]

After two problem-free years with my '09 speedy, I now have a recurring problem. I have 15K miles on her now with original battery.
Unlike other posters, she starts up on first or second try with plenty of gusto, even when idle for a week and garage temp of 50F. The problem has occurred several times now: I stop to gas up, typically don't even get off bike, so takes a couple minutes I guess. I hit start and it starts to crank then stops. After a few attempts, my buddies heads begin to sink, then it fires up and I'm off. Yesterday, no such luck, but I was near a hill and roll started it. (after I learned that this should be done in second gear! I couldn't figure out why my rear wheel was locked in 1st gear). We later stopped a half hour for coffee and she roared to life without problem. I conclude that it is the very brief stop that is to blame...thoughts?
Thanks!

[FoothillRyder]

Lots of variables here; but my first question is: How do you maintain your battery?

Bikes in general (and perhaps S3's in particular) are very sensitive to the condition of the battery - and the condition of the connections in the charging and starting circuits. If the battery isn't very strong, this kind of thing can happen. The starter draws more current from the battery than does any other single component, which can drop the voltage available to run everything else when the starter is cranking the engine. The ECU requires a certain voltage to do its job, and it is possible that it isn't getting what it needs.

Or... it's always the battery.

[drsib]

Hmm. I might end up with a new battery, but your reply doesn't explain what I'm experiencing. I have complete confidence that I can walk into garage right now and start her on first or second try. But after four problems after getting gas, I'm looking for downhills and considering leaving my bike running for quick stops. Perplexing, right?
My battery maintenance= riding every week. I put it on tender if I won't be riding. Terminals look great.

[Jeremy J]

I don't have a solution for you but you might try searching for "hot start issue" or something similar. I've seen that type of problem on plenty of cars and a few different solutions. Seems like I remember a starter not liking heat on a friends car. He had to sit for 30 minutes after shutting it off or it would just click.

[Joe Houle]

Put it on a full size charger that desulfates, not just a battery tender. Once its desulfated and topped off, load test it.

[DEcosse]

Does it seem like it cranks slow, or either doesn't crank and just clicks?

If the former, battery probably just past its best, assuming the generating system is good (check the voltage across the battery with engine running)

If the latter, look for broken key-switch harness - does situation change if you rotate the bars back & forward or pull on the switch cable harness?

[bevivino1]

Do a check for parasitic drain. Do a google search, very easy if you have a decent multimeter. If you think battery is issue.

[drsib]

Originally Posted by DEcosse

does situation change if you rotate the bars back & forward or pull on the switch cable harness?

Damn, I think you may have nailed it DEcosse! Everytime I shut my bike down I turn the handlebars full left and remove key at the locked position. BUT, when I get gas I leave the handlebars neutral.

The "hot start" issue also makes some sense. I still have a hard time with the "bad battery" angle since it starts up easily after sitting for a week.

I'll do some testing...
Thanks for the ideas! (And thank you DEcosse for the group buy on the MOTOMFG stand!)

[jalapenos]

Check all your ground connections for cleanliness and tighten. Your condition sounds like a ground fault to me...

[FoothillRyder]

After sitting for a week (or even an hour) the ECU is nice and cool, and will have different needs vis-a-vis supply voltage than it does after it's gotten nice and hot on a ride. Not trying to defend my point, just providing some clarification.