Engine stall after turn signal stops flashing

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

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FabriceAllaz
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Suzuki 2-Strokes: GT 250 (K),XT 250 past in OZ,
Location: Switzerland

Engine stall after turn signal stops flashing

Post by FabriceAllaz »

Hi,
I have a Gt 250 K (1973), the bike stalled on me after a put the turn signal on and it stops flashing,but the turn indicator light was on.
After impossible to start the bike, it same that the battery was very flat as the light for neutral was very wick, barely visible.
It did start fine 5 min. before with good? battery power. The bike as only a kick start anyway.
This is the third time it happens to me, with a fews weeks interval.Every time it happens I make sure that I recharge the battery, will see tomorrow if it help.
My questions are,
with a kick start I should be able to start it no matter the battery charge, right?
Is it a short with the turn signals?
Or finally is my battery not getting charged and soon as use to much electrics it stall? But I always ride with lights on.
If someone as idea or can shed some lights on the subject it would be great,
Cheers,
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Alan H
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Re: Engine stall after turn signal stops flashing

Post by Alan H »

Your battery may be bad. Can you borrow a good one to see if that runs OK?
Check the battery voltage when the engine is running. Should be more than 13 volts.
Check the battery voltage when the engine is off and battery charged - should be at least 12.5 volts.
Does the voltage rise when the engine is revved?
You won't start the engine on kick if the battery is flat. You need good voltage to the coils and points to start and run.
Check that the battery voltage is more than 13 volts with engine running and lights on. If not, you have a charge/battery problem.
How long can you use the lights/indicators before the battery voltage drops below 12 volts. At that - it's flat. Normal fully charged should be about 12.8 volts.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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jabcb
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Re: Engine stall after turn signal stops flashing

Post by jabcb »

Is your electrical system & lighting stock?

Your bike uses the battery as the voltage regulator.
So do not try to run the bike without a battery or you may burnout the lights.

The GT250//T250/T350 have a permanent magnet alternator.
Some will start and run fine without a battery (but burnout the lights).
Others won’t start or won’t run good without a battery.

Remove the battery. Check the water level in the battery & add distilled water if needed.
Fully charge the battery.
Leave the battery sit overnight & check the voltage. Should be around 12.4 to 12.8V.
If its less than 12V the battery is shot.

You bike has a switched alternator with a charging coil & a lighting coil.
The lighting coil only provides power when the lights are on.

If your battery is good, proceed with the next test.
Install & connect the battery.
With the lights off, check the rpm where the alternator starts to charge the battery.
(Check when the battery voltage starts to climb about the voltage you measured per the above test.)
Repeat the test with the lights on.
Both should occur by 2k rpm.

Let us know how these tests go.
Let us know if you need a new battery — there are some issues to consider before selecting the new battery.
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
FabriceAllaz
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Suzuki 2-Strokes: GT 250 (K),XT 250 past in OZ,
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Re: Engine stall after turn signal stops flashing

Post by FabriceAllaz »

Hi Jabcb,

I charged the battery all night, didn't check how many volts I had :( , anyhow this morning 13.4 V. And this afternoon 12.8 V. after about 9 h., I will check tomorrow morning after 24 h., no use just seating on the bench.
The batterie is new, only 2 months on the bike 12V 5 ah. from Yuasa.
If ok, I will proceed with the next test.

Cheers,
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akendall1966
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Re: Engine stall after turn signal stops flashing

Post by akendall1966 »

It happened when you used the indicator. Unplug the flasher relay and try, relay could have gone bad and shorted robbing the electrics of volts.
FabriceAllaz
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Suzuki 2-Strokes: GT 250 (K),XT 250 past in OZ,
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Re: Engine stall after turn signal stops flashing

Post by FabriceAllaz »

Thank all of you sugggestion,
Batterie seems ok, it settled at 12.8V., but when engine running drops to 12.2 ( light or not) and rise to 12.4 when reving to above 2000-3000.
It looks like I have some old connection which I will replace today.
It stalled again yesterday after a big ride refueling start( first quick as usual when warm), at the stop sign, stall no power at all!
Nothing for 10 to 15 mn., then power again, start first quick.
Is it possible a coil, condenser or else gets to hot and " stick" cutting all electrical power, remembering it is from 1973 so no electroniques what so ever.

Cheers,
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ConnerVT
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Re: Engine stall after turn signal stops flashing

Post by ConnerVT »

I believe your charging system is not charging. 12.2-12.4V is much too low.
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jabcb
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Re: Engine stall after turn signal stops flashing

Post by jabcb »

Those are bad numbers.

The wiring diagram for the 1977 GT250B is here: download/file.php?id=826
You bike is the same, with the exception that it does not have a voltage regulator (labeled “Regulator” in the diagram).


First step would be to check the alternator stator.

The stator has 4 wires: Y/G, R/G, G & G/W.
In the as-delivered setup:
1) the charging coil wires are Y/G — R/G
2) the lighting coil wires are Y/G — G/W and Y/G — G
To increase output with the lights off, some bikes are setup:
1) the charging coil wires are Y/G — R/G and Y/G — G (the stator G wire connects to the stator R/G wire)
2) the lighting coil wires are Y/G — G/W

Disconnect the battery & alternator.

If your multimeter has manual range settings, use the lowest resistance setting.

Measure the resistance between each of the four stator wires & ground (some unpainted surface on the motor).
You should get an open circuit for all four.

Check coil resistances for each coil: Y/G — R/G, Y/G — G/W and Y/G — G
You should get low readings.

As a reference point, check the internal resistance of your multimeter.
(Touch the two probes together to measure the resistance.)

Let us know how the results.


Its more likely that the problem is something other that the stator, but checking the stator is a good first step.

If you have electrical problems & the stator is OK, the cleanest solution is to upgrade the bike to a modern rectifier/regulator.
If you want to keep the wiring 100% stock, then the next steps would be to check the rectifier & look at the wiring for obvious problems.

I’ve had a few rectifiers go bad, and generally just upgrade to a modern rectifier/regulator.
This allows you to also upgrade to an AGM battery.
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
FabriceAllaz
Still in the Driveway
Posts: 5
Joined: Sun Aug 09, 2015 12:51 pm
Country: Switzerland
Suzuki 2-Strokes: GT 250 (K),XT 250 past in OZ,
Location: Switzerland

Re: Engine stall after turn signal stops flashing

Post by FabriceAllaz »

Will Check,thank you.
Soon it is winter and I will have time to give a good upgrade to the electrical system.

Cheers,
are
Still in the Driveway
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Joined: Tue Oct 20, 2015 3:55 pm
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Suzuki 2-Strokes: GT250K

Re: Engine stall after turn signal stops flashing

Post by are »

Mine did the same. I just bougth the bike.
Mine starts well even with low battery. The fault is in the charging system, the rectifier is faulty if it is still stock. The other reason is the lightning switch, when lights on, the charcing current goes via the switch.

Buy 5-wire regulator/reftifier, this is good: Shindengen S4T-05 It ist used in old Hondas
The leads from alternator: yellow with green tracer, red with green tracer and green with white tracer (connect the green one to this too) are the charcing leads. Connect them to regulator/rectifier yellow leads. The red from regulator/rectifier to battery positive and green to ground. The red from fuse to the red from regulator/rectifier too.

Note that after all is done, the red with green trace which goes to lightnin switch is now empty.

And now, it just rocks!

If there is old regulator, take it away. In mine there was, under the saddle.
FabriceAllaz
Still in the Driveway
Posts: 5
Joined: Sun Aug 09, 2015 12:51 pm
Country: Switzerland
Suzuki 2-Strokes: GT 250 (K),XT 250 past in OZ,
Location: Switzerland

Re: Engine stall after turn signal stops flashing

Post by FabriceAllaz »

Thanks are,
Sounds lime a good advice, I had as well the + wires from the batterie (after the fue) in 3 sections for no reasons and replaced with a good section.
The other day I had as well one of the RH piston stop firing ? I had sparks on both but I decided to swap the sparks plugs ( the one running LH nice and brown, the RH wet and black ), after cleaning theme, both piston started firing after 50 km. the bike works great but I will check both plug soon.

As said before winter is coming and the bike will be parked and a good electrical overall will take place.

Cheers,
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