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UTC

Lurker
06 GTS250
Joined: UTC
Posts: 2
Location: VA
 
Lurker
06 GTS250
Joined: UTC
Posts: 2
Location: VA
UTC quote
How can I test the voltage regulator on a GTS 250 to see if it's functioning correctly? Is there a spec sheet I can look at (download) somewhere to compare readings with a DMM? What are signs of a faulty volt reg? What could cause a rattling sound that seems to be coming from the front region of the scoot?
UTC

Ossessionato
Joined: UTC
Posts: 3610
 
Ossessionato
Joined: UTC
Posts: 3610
UTC quote
Use a voltmeter and measure the voltage at the battery with the scooter idling: It should read around 12.7 volts. Then test it with the engine being revved over 3k rpm's and it should not exceed 14.8 volts. If you get a high readng while being revved, it's the voltage regulator. I had one go bad on a BV500 (same VR) and it was reading 18 volts when it was revved and the check engine light would come on whenever the engine was revved but it would go out when it went back to idle. It also made a knocking sound.
⬆️    About 5 years elapsed    ⬇️
@bendcyclist avatar
UTC

Molto Verboso
2006 GTS 250ie in Silver
Joined: UTC
Posts: 1808
Location: Bend, OR
 
Molto Verboso
@bendcyclist avatar
2006 GTS 250ie in Silver
Joined: UTC
Posts: 1808
Location: Bend, OR
UTC quote
sorry to rehash an old thread but...

My battery is at 12.1 when the bike is off.
When at idle it's 14.1
When at 3000-4000 rpm it's at 13.2

Any advice or is this normal?
UTC

Addicted
2015 BV350 2007 GTS(sold) 2003 BV200
Joined: UTC
Posts: 774
Location: nyc
 
Addicted
2015 BV350 2007 GTS(sold) 2003 BV200
Joined: UTC
Posts: 774
Location: nyc
UTC quote
recheck the voltage at the battery when at 3 or 4000 rpm hold it for 30 to 90 seconds. see what you get.

12.1vdc standing battery is low.

John
@bendcyclist avatar
UTC

Molto Verboso
2006 GTS 250ie in Silver
Joined: UTC
Posts: 1808
Location: Bend, OR
 
Molto Verboso
@bendcyclist avatar
2006 GTS 250ie in Silver
Joined: UTC
Posts: 1808
Location: Bend, OR
UTC quote
It drops off to 13.1

It's a brand new battery too.
UTC

Addicted
2015 BV350 2007 GTS(sold) 2003 BV200
Joined: UTC
Posts: 774
Location: nyc
 
Addicted
2015 BV350 2007 GTS(sold) 2003 BV200
Joined: UTC
Posts: 774
Location: nyc
UTC quote
slow charge the battery out of the scooter. Let it sit a few hours and recheck the battery voltage. If the battery will not hold 12.6 or above I would send it back defective.
That battery could be affecting the charging voltage.

John
@bendcyclist avatar
UTC

Molto Verboso
2006 GTS 250ie in Silver
Joined: UTC
Posts: 1808
Location: Bend, OR
 
Molto Verboso
@bendcyclist avatar
2006 GTS 250ie in Silver
Joined: UTC
Posts: 1808
Location: Bend, OR
UTC quote
I will do that. I had to replace the battery because the 1 year old Motobatt died. I bought another Motobatt and it was reading a much higher voltage when it first was installed.
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