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Discussion Starter #1
First off this is on my 02 SP2 with less than 8k miles. I've never had a single issue with the bike until now. I also just moved the bike from Phoenix to Denver. The bike was running great here for about a week. Not sure if it's relevant but background is always good. Onto my issue..

I walked out to my bike yesterday morning to see nothing turn on with the turn of my key.. Okay, battery duh. Pull off my seat and I've got a loose terminal. Of course, I tighten it back up and the battery is weak so I throw my tender on and take the car.
This morning, I head down to my bike, button everything up and voila, RC starts. So I let it run while I gear up, about 5 minutes. At this point my bike has already peaked 115 operating temp so I roll out of my garage, give it a quick blipright before I'm about to pull off and it dies..try to start it, and it just continues to turn over but won't fire..pull back in the garage to do a quick once over to find nothing out of the ordinary. I tried to start it again and it fired for about a second and died..

Anyone got any ideas? Nothing on the bike has changed recently so Im lost. My initial thought would be fueling..
 

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I would start from the battery....it is possible it is damaged and cannot store the charging.
While the bike is at idle you should measure 13,5-14,5V on your battery's terminals. Same reading at 4000rpm and 0.5V less with your high beam on.

After 12 hours on the tender/charger the battery should read 13,2-12,9V for at least 3-4 days if you let it rest on a bench. That voltage reading also means that the regulator/rectifier work as it should.

After charging it really good, remove the negative terminal and let it rest over the night.
In the morning you should read a minimum 12,8-12,9V on it's terminals.
Otherwise, the battery is toasted.
 

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Discussion Starter #3
I would start from the battery....it is possible it is damaged and cannot store the charging.
While the bike is at idle you should measure 13,5-14,5V on your battery's terminals. Same reading at 4000rpm and 0.5V less with your high beam on.

After 12 hours on the tender/charger the battery should read 13,2-12,9V for at least 3-4 days if you let it rest on a bench. That voltage reading also means that the regulator/rectifier work as it should.

After charging it really good, remove the negative terminal and let it rest over the night.
In the morning you should read a minimum 12,8-12,9V on it's terminals.
Otherwise, the battery is toasted.
I also have the lighter YTZ7S battery. I've never had this sort of issues before and I've only had this Battery for about a year.

You think this could still be the issue even though it started it up, and then didn't sound weak after dieing?
 

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i vote for fueling problem. only coz mine did that and i was running on fumes trying to get to the dang gas station. lol
 

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Discussion Starter #6
i vote for fueling problem. only coz mine did that and i was running on fumes trying to get to the dang gas station. lol
Well there's definitely gas in the tank haha. But all of a sudden? I will start with the battery. It's on the tender all day while I'm at work.
 

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Discussion Starter #7
Come to think of it, could it have to do with my fueling map just being way too rich and it fouled the plugs while idling? The bike is tuned for Phoenix, and now Im in Denver, which is quite the elevation change (1000 vs 5300 feet)
 

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Come to think of it, could it have to do with my fueling map just being way too rich and it fouled the plugs while idling? The bike is tuned for Phoenix, and now Im in Denver, which is quite the elevation change (1000 vs 5300 feet)
i doubt it if the bike was running great the first week, unless weathers changed dramatically i cant see it being that, i'd start with the battery, sounds like the kinda silly stuff bikes do with a half dead battery, especially with temp gauge acting funny
 

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You can push start a bike and it will then start and run with a weak battery, (<10v) so there is no reason that the battery would crank the bike over and not have enough juice to provide a decent spark.

My vote is for a fuel issue.
 

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Well, obviously start w/the battery, but if you replace it w/a new one and still have the problem, look at the rectifier. One thing I recently learned about them (RC's) w/the rectifier mounted int he tail section.....it gets really hot in there and they overheat and fry. I've replaced 2 rectifiers since I got my SP2 back in 2010. After the 2nd one, I took my dremel and cut some small slits in the tail to allow airflow directly in there and to help keep the rectifier cool. So far, no problems. Some people also relocate the rectifier. Something else to think about.
 
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