Electrical issue, unsure what though?!

Squeaky back brake? Hard to control at 30mph/40kph?
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Blakey58
50cc
50cc
Posts: 4
Joined: Wed Sep 07, 2016 8:38 pm
Country: United Kingdom
City: Portsmouth
Year: 2009
Model: SMT

Electrical issue, unsure what though?!

Post by Blakey58 » Tue Mar 28, 2017 11:07 am

Morning All,
Had an issue with my SMT at the weekend, i'll start with some background info.
Battery is maybe 5 months old max, genuine Yuasa. Bike has been in a garage and kept plugged into a trickle charger(Not Ridden since Nov. due to re-registering issues).

So i took it out Saturday, started fine no issues. Did about 30 miles when i stopped i noticed the FI light was on, i thought this was strange never seen it come on before and had no issues with the bike on my ride.

stopped for approx. 40 mins or so, when to start the bike back up and all the lights flashed on the dash then it reset itself. i could here an audible click when i pressed the start button so i assumed flat battery and got some people to help push start it(what a mission that was! :evil: ).
riding home everytime i went to low RPM the battery warning light came on, assuming the regulator to be faulty as even at idle it should make 14v or so ? i stopped for fuel and low and behold, it wouldn't start again!
Eventually i got home, let it charge overnight on the optimate charger and the following day I put a multi meter on it.

13.2V, Turned the ignition on, dropped down to 12.3V and leveled off, Started it and went to 14.2V at idle and stayed there.
Turned it off, measured again at 12.8V so i left it for 2 hours and checked it to still be at 12.8V.

I assumed it to be regulator which it doesn't look to be, Does anyone have any input I'm totally lost on what's going on with it

Thanks

Random00
125cc
125cc
Posts: 30
Joined: Mon Jan 23, 2017 5:11 pm
Country: United States
City: Los Angeles
Year: 2013
Model: SMT

Re: Electrical issue, unsure what though?!

Post by Random00 » Tue Mar 28, 2017 5:17 pm

First, check the battery terminals. Make sure both are snug/tight.

It sure sounds based off what you're describing is either a battery that is in it's death throws, or a charging system that's not keeping the battery charged.

Only way to tell is to leave the battery off the charger for 24 hours. If the voltage drops more than 12.1V, something is wrong.

Pull the battery and charge it back up. Then leave it out of bike/disconnected for 24 hours. If voltage again drops to 12.1V, it's going south. See if you've got your receipts to warranty your battery.

If battery tests fine IN the bike, you'll need to hook up a volt meter/multi-meter where you can see it when riding. You can get cheap bar mounted voltmeters off amazon/ebay for under $20. See if your voltage every drops below 12.5 while riding. If so, you'll have to test both your stator and your Regulator/Rectifier to find the source of the problem.

Blakey58
50cc
50cc
Posts: 4
Joined: Wed Sep 07, 2016 8:38 pm
Country: United Kingdom
City: Portsmouth
Year: 2009
Model: SMT

Re: Electrical issue, unsure what though?!

Post by Blakey58 » Tue Mar 28, 2017 5:31 pm

I've just got home and checked it. 12.77v so it's held steady over the last 24 hours since i last checked it.

Voltage is reading what it should at idle so like you say i probably need to check all the connections and read off voltage while riding it

Blakey58
50cc
50cc
Posts: 4
Joined: Wed Sep 07, 2016 8:38 pm
Country: United Kingdom
City: Portsmouth
Year: 2009
Model: SMT

Re: Electrical issue, unsure what though?!

Post by Blakey58 » Wed Mar 29, 2017 10:40 am

Rode it last night only about 5 miles, Voltage had increased when i got back. I also didn't see the battery warning light flash up on this ride either so either Saturday was a total fluke or I've got a bad connection somewhere.

I'll take the battery terminals off and clean them up. Any other likely culprits to inspect & clean up? The ground if i can figure out where it is

Magic Wand
Supporter
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Posts: 359
Joined: Mon Jun 08, 2015 8:40 am
Country: Sweden
City: Sthlm
Year: 2010
Model: SMT

Re: Electrical issue, unsure what though?!

Post by Magic Wand » Wed Mar 29, 2017 3:42 pm

"Blakey58"

The ground cable should be found attached on the right side of the engine. Simply follow the black cable from the battery!

/M

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