GT185 Charging System (DC) question

All to do with wiring, charging or just trying to figure out whats gone wrong.

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Flywheel
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GT185 Charging System (DC) question

Post by Flywheel »

Just seeing if this is a common occurance with a strictly DC charging system. On my GT185 the battery needs charged every 3-4 months. Battery is one year old, takes a charge, however after riding over time the battery will seem to get "low"? The bike will start, headlight on, but the turn signals will not operate unless the RPMs are above 3000rpm. I checked the cut in voltage before the regulator as the manual states, it's inbetween 13.5 - 15.4 Volts depending on RPM. Ok per the manual. I'm thinking this charging system was designed to charge without the headlight being on at all times, thus the battery will need charge once every so often. Anyone have a similiar experience with a GT185 doing this? Comments from others? BTW I do disconnect the terminals from the battery every time after riding.
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jabcb
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Re: GT185 Charging System (DC) question

Post by jabcb »

You may see some benefit from going through & cleaning the wiring connectors for the generator & voltage regulator.
Also check the condition of the voltage regulator contacts if you can.

Do you have the stock headlight?

How did the Seca 400 work out?
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
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GT550 72 & 75
GT380 72
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Alan H
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Re: GT185 Charging System (DC) question

Post by Alan H »

Fit a couple of these
http://www.ebay.co.uk/itm/2pcs-White-4- ... 19e9077a11" onclick="window.open(this.href);return false;
They don't use 'any' amps and your battery should be OK. It should be OK even running with the lights on though. I also fitted some LED stop/tail bulbs to the 550 to help a bit especially in stop/start riding.

If you have a 'cheap' battery and the levels are down that will cause problems. What is the battery voltage after a few days without running?
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Flywheel
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Re: GT185 Charging System (DC) question

Post by Flywheel »

Jabcb:
Some good thoughts. I did clean the commutator (sp?) whenever I installed new brushes and cleaned the voltage regulator's contacts. I did not however check or clean any of the interconnects/plugs in the wiring harness. That will need to be done. Headlight is stock Kaito. I'll PM you on the Seca.

Alan H.
Unfortunelty I didnt check voltages after every ride. After I charge it with a 1amp charger for 5 hours I get a reading of 12.8V after a couple months of riding and it's starting to get "weak" I measured it twice 11.6 and 11.8V
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Re: GT185 Charging System (DC) question

Post by Alan H »

It's possible that the battery isn't very happy.
I fitted a Motobatt to the 550 and the difference is immense. Never gets discharged, and always spins the motor really well even after several tries (like 20!!) when I first got the bike running. I had soaked the seals and crankcases in diesel, then overoiled everything before trying to start the engine and it just didn't like a diet of oily petrol rather than petrol-y oil!
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Flywheel
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Re: GT185 Charging System (DC) question

Post by Flywheel »

Could be, it's a cheapo Exide vented wet cell battery. I'm going to check all the conections/plugs on the wiring harness like jabcb suggested. If no luck with that, then a new battery. BTW I just checked the voltage tonight, 12.20V. Bike was last rode this past Saturday with no issues and the last time I charged the battery was approx. 3-4 weeks ago.
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Re: GT185 Charging System (DC) question

Post by jabcb »

The voltage regulator has two relays.
The cut-out relay connects the generator to the electrical system & the other controls max voltage.

Charge the battery up & then check for the voltage that these two relays operate at.

The difference between the two voltages is important.
For example, you won't get much alternator output if the max is controlled 13V & the cut-out acts at 13.5V.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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Flywheel
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Re: GT185 Charging System (DC) question

Post by Flywheel »

Okay, I understand what your saying. I have a schematic, so first thing is to detemine which relay controls what, then get measurements. Thanks again.
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