T500 battery not charging.

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

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Fritz500
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Suzuki 2-Strokes: Suzuki TS90, TS250, T500 (4), GT750
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T500 battery not charging.

Post by Fritz500 »

I had a problem with the battery not charging some time ago and it turned out to be the voltage regulator was kaput. Fitted a spare and everything went back to normal. That was about a year ago.

Noticed the the indicators weren't flashing properly the other day so I checked the battery voltage, it was down to about 10.5 volts. Charged it up and the bike ran fine and the lights etc all looked good. Checked the battery voltage and it was 12.8volts with the bike stopped and 11.8 when it was running.

Decided to check the alternator.

Unplugged the alternator wires from the harness and rectifier. (Resistance of less than 1 ohm was expected)
- Resistance G/W to Y/G = 0.9 ohms
- Resistance R/G to Y/G = 0.8 ohms
- all wires to ground = open resistance.

Checked the AC output (expecting to see 35 to 40 volts) at 2500rpm:
- RG/YG = 30 - 35 volts
- YG/GW = 0 - 20 volts (values varying rapidly)

Given that the resistance values were OK I was surprised to see the output voltage was screwed up.

Any thoughts guys?

Cheers
73 GT750 Ducati - 20%
72 T500J - 95%
09 Yam XVS950A
81 Yam XV920 - cafe conversion - 90%

“Anyone who believes a perpetual motion machine is impossible has no imagination; anyone who thinks it is possible has no education.” Adam Peenum
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jabcb
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Re: T500 battery not charging.

Post by jabcb »

The G/W wire is for the lighting coil.

Do you have good voltage at the battery with the bike running & the lights off? (What is the voltage at 2k & 5k rpm?)

There might be an intermittent short that's affected by engine vibration.
Check the alternator wires for insulation damage.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
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Fritz500
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Suzuki 2-Strokes: Suzuki TS90, TS250, T500 (4), GT750
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Re: T500 battery not charging.

Post by Fritz500 »

jabcb
I tested everything according to this post:
viewtopic.php?f=29&t=6566&p=119934&hili ... er#p119934" onclick="window.open(this.href);return false;

Sounds like the guy knew what he was talking about. :up:

The battery voltage dropped from 12.8 volts (with the bike stopped) to 11.8 volts when it was running at 2500rpm.

I pulled out the stator and it appears to be in mint condition. No damage to the windings or connecting wires. This is a low mileage T500 that has been out of the weather all of its life.

I went through this whole exercise about a year or two ago when my voltage regulator turned out to be the problem.

I should be getting about 40v between the G/W & Y/G but get wildly varying low values. There are no connections between the point I test the voltage and the stator so I have eliminated the idea of faulty connections. The resistance readings are all good.

I have another stator on another 500 I'm restoring...it'll be a pain but I'll have to do the swap to see if it is the stator that is faulty.

Thanks for your help so far.

Cheers

Geoff
73 GT750 Ducati - 20%
72 T500J - 95%
09 Yam XVS950A
81 Yam XV920 - cafe conversion - 90%

“Anyone who believes a perpetual motion machine is impossible has no imagination; anyone who thinks it is possible has no education.” Adam Peenum
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Fritz500
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Suzuki 2-Strokes: Suzuki TS90, TS250, T500 (4), GT750
Location: Perth, Western Australia

Re: T500 battery not charging. Solved

Post by Fritz500 »

Checked the voltage after the rectifier (about 30 - 35 vdc) and it was working OK. Swapped to a spare one and got the same output.

Swapped over to a spare voltage regulator and bingo! voltage to battery rose to about 13.6 volts at 2500rpm. So this is the second regulator that has gone kaput in two years.

Time to buy a modern combination rectifier/regulator...
73 GT750 Ducati - 20%
72 T500J - 95%
09 Yam XVS950A
81 Yam XV920 - cafe conversion - 90%

“Anyone who believes a perpetual motion machine is impossible has no imagination; anyone who thinks it is possible has no education.” Adam Peenum
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Fritz500
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Posts: 495
Joined: Sat Jan 22, 2011 11:12 pm
Country: Australia
Suzuki 2-Strokes: Suzuki TS90, TS250, T500 (4), GT750
Location: Perth, Western Australia

Re: T500 battery not charging.

Post by Fritz500 »

Does anyone have experience with putting a GT500 voltage regulator into a T500? The GT500 version has two wires and the T500 version has 3 wires.


Cheers
73 GT750 Ducati - 20%
72 T500J - 95%
09 Yam XVS950A
81 Yam XV920 - cafe conversion - 90%

“Anyone who believes a perpetual motion machine is impossible has no imagination; anyone who thinks it is possible has no education.” Adam Peenum
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