Idle picks up when headlight switches on
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- PippiFyrecracker
- Around the block
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- Joined: Mon Apr 06, 2015 6:17 pm
- Country: Canada
- Suzuki 2-Strokes: 1975 T500, 1983 SP250
- Location: ottawa, ontario, canada
Idle picks up when headlight switches on
Rpm of idle increases and bike seems to run better when headlight is turned on decreases when turned off. Thoughts? I need to trouble shoot, blinkers stopped working too... Where to start?
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Re: Idle picks up when headlight switches on
Sounds like you have a poor connection somewhere. First thing I would do is start cleaning and replacing earth connectors. Check also any and all connector blocks for corrosion or breaking wires, especially inside the headlamp. It may take hours to clean or replace connectors, but if done properly it will eliminate many future electrical glitches. I replaced almost every single connector and terminal on my wiring loom to avoid problems like this. It took an age, but now all of my terminals are soldered and crimped with fresh metal. If you find an auto wiring shop online they can usually supply most of what you need to revitalise old looms, including proper japanese size bullet connectors and sleeves.
P.S. Don't underestimate the power of flux when soldering new terminals to old wire.
P.P.S. Remember, crimped terminals do not always make good contact on old blackened wire. If in doubt, solder it and cover in heat-shrink.
Good luck
P.S. Don't underestimate the power of flux when soldering new terminals to old wire.
P.P.S. Remember, crimped terminals do not always make good contact on old blackened wire. If in doubt, solder it and cover in heat-shrink.
Good luck
- ConnerVT
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Re: Idle picks up when headlight switches on
Or another perspective:
The T500 has 3 sets of generator coils. Assuming stock wiring, when the headlamp is switched off, only one set of coils are working. Switch the headlamp on, all 3 sets of coils are working. This was to limit the amount of current generated when the lights were off (low load), to help prevent overcharging the battery.
If your battery is marginal, there is a poor connection somewhere, or the headlamp switched off coil is weak, there may not be sufficient voltage for the bike to run properly. Turn on the headlamp, you now have 3 coils operating, and that may be supplying more current (even with the additional headlamp load) than the single 'lights off' coil is.
added: Start reading at page 84 - http://file.walagata.com/w/sundialmotos ... kiT500.pdf
The T500 has 3 sets of generator coils. Assuming stock wiring, when the headlamp is switched off, only one set of coils are working. Switch the headlamp on, all 3 sets of coils are working. This was to limit the amount of current generated when the lights were off (low load), to help prevent overcharging the battery.
If your battery is marginal, there is a poor connection somewhere, or the headlamp switched off coil is weak, there may not be sufficient voltage for the bike to run properly. Turn on the headlamp, you now have 3 coils operating, and that may be supplying more current (even with the additional headlamp load) than the single 'lights off' coil is.
added: Start reading at page 84 - http://file.walagata.com/w/sundialmotos ... kiT500.pdf
- jabcb
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Re: Idle picks up when headlight switches on
Blinkers likely stopped working because the voltage is too low.
As ConnerVT said, the T500 alternator has charging & lighting coils. If you are getting no output from the charging coil, then the only alternator output occurs when you turn the lights on. So the voltage might increase when you turn the lights on. With increased voltage, the bike then runs better.
You can verify that this is the problem by checking voltages.
To start investigating, charge up the battery. Then check the voltage:
1) with the bike off
2) with the lights off at ~2k rpm
3) with the lights on at ~2k rpm
4) again with the bike off
As ConnerVT said, the T500 alternator has charging & lighting coils. If you are getting no output from the charging coil, then the only alternator output occurs when you turn the lights on. So the voltage might increase when you turn the lights on. With increased voltage, the bike then runs better.
You can verify that this is the problem by checking voltages.
To start investigating, charge up the battery. Then check the voltage:
1) with the bike off
2) with the lights off at ~2k rpm
3) with the lights on at ~2k rpm
4) again with the bike off
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more
Suzuki:
GT750 2x75
GT550 72 & 75
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T500 69 project & 73 project
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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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Re: Idle picks up when headlight switches on
Aha. Now you see that is where a bit of model specific knowledge is very useful. I didn't know this about the T500. I would definitely suggest you check what Connor and Jab suggested first.ConnerVT wrote:Or another perspective:
The T500 has 3 sets of generator coils. Assuming stock wiring, when the headlamp is switched off, only one set of coils are working. Switch the headlamp on, all 3 sets of coils are working. This was to limit the amount of current generated when the lights were off (low load), to help prevent overcharging the battery.
If your battery is marginal, there is a poor connection somewhere, or the headlamp switched off coil is weak, there may not be sufficient voltage for the bike to run properly. Turn on the headlamp, you now have 3 coils operating, and that may be supplying more current (even with the additional headlamp load) than the single 'lights off' coil is.
added: Start reading at page 84 - http://file.walagata.com/w/sundialmotos ... kiT500.pdf
- PippiFyrecracker
- Around the block
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- Suzuki 2-Strokes: 1975 T500, 1983 SP250
- Location: ottawa, ontario, canada
Re: Idle picks up when headlight switches on
update, ripped out the wiring, found some bad grounds, ordered power dynamo electronic ignition, rewiring everything from scratch. probably buying new battery as well...
- dorT500
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Re: Idle picks up when headlight switches on
YIKES!PippiFyrecracker wrote:update, ripped out the wiring, found some bad grounds, ordered power dynamo electronic ignition, rewiring everything from scratch. probably buying new battery as well...
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GONE.......WITH A PUFF OF SMOKE AND A BLUR OF SPOKE
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GONE.......WITH A PUFF OF SMOKE AND A BLUR OF SPOKE
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Re: Idle picks up when headlight switches on
Expensive way to go, but probably the best way to do it.PippiFyrecracker wrote:update, ripped out the wiring, found some bad grounds, ordered power dynamo electronic ignition, rewiring everything from scratch. probably buying new battery as well...
- PippiFyrecracker
- Around the block
- Posts: 66
- Joined: Mon Apr 06, 2015 6:17 pm
- Country: Canada
- Suzuki 2-Strokes: 1975 T500, 1983 SP250
- Location: ottawa, ontario, canada
Re: Idle picks up when headlight switches on
tired of running into issues every other time i ride the bike, doing a rebuild...