Intermittent Starter Issues | GTAMotorcycle.com

Intermittent Starter Issues

Wheelieboy

Well-known member
Bike: 2007 DRZ400SM

Last summer, I started to have intermittent starter issues which got worse very quickly. One day I wasnt able to start the bike using the starter, I tried to bump start it but didnt get enough speed to successfully do it, and I decided to try the starter button again and it worked.

As the weeks went on, the problem started to show itself more often...and to get it to start, I put it in gear, rolled the bike forward/back and tried again. I assumed that there was a worn contact point/motorbrush and if I moved the bike, it would come into contact again....or the jarring/vibration motion somehow helped it.

Now, it takes more than 10 attempts of back/forward before the starter turns the motor.

Things to note:
-I've replaced the starter motor and still have the same symptoms
-Battery is strong enough to crank
-When I press the starter button, the headlights dim everytime as expected so it seems like the starter button is working
-Maybe related?...my rear running light sometimes doesnt work, but the brake light turns on when the brake is depressed

I dont really know how to go about troubleshooting anymore as I'm not good with electrical. How would I troubleshoot this issue? Should I use a multimeter on the starter? Starter button? Battery?
 
rolling the bike is not going to reposition anything within the starter
so I'm going to guess it is like you said: moving the bike affects whatever the bad connection is

a schematic and meter would be the proper way to TS the system
a quick cheat is to look for any physical loose connections
particularity any where you see the green fuzzies
the other components to check would be the button and start relay
side-stand switch is also a likely culprit
my money is on a bad connection somewhere
 
My first place to look is always both ends of the ground cable. Very rarely do I have to go on to step B of the diagnostic.
 
"Now, it takes more than 10 attempts of back/forward before the starter turns the motor."

Does this mean that when you try to start the bike the starter turns but the motor does not?

What is battery voltage at rest, bike off.
What is battery voltage at rest, bike switched on, not running.
What is battery voltage at rest, bike switched on, running.
What is battery voltage when the starter is turning?
 
a schematic and meter would be the proper way to TS the system
a quick cheat is to look for any physical loose connections
particularity any where you see the green fuzzies
the other components to check would be the button and start relay
side-stand switch is also a likely culprit
my money is on a bad connection somewhere

Side stand switch is not connected so its not that. I'll look for loose connections

My first place to look is always both ends of the ground cable. Very rarely do I have to go on to step B of the diagnostic.

Ground cable to which? The starter motor or the switch? Theres only 1 wire going to the starter motor and I assume its power. Starter motor gets grounded by the engine block correct?

"Now, it takes more than 10 attempts of back/forward before the starter turns the motor."

Does this mean that when you try to start the bike the starter turns but the motor does not?
10 x of pressing the starter button, then moving the bike back and forward.
Starter does not turn when I press the button, but the button is somewhat 'working' since the headlights turn off when I press it.

Solenoid?
How do I check this?
 
Test the coil side of the starter relay where it plugs in to confirm there is 12 volts there when you push the button (yellow/black to grey/black). Disconnect the relay from the battery and continuity test the point contact side to make sure there is zero resistance between the battery connection and starter. Starter motor is grounded to the motor but the grounding between the battery and the motor needs to also show zero resistance.

2008-drz-sm-wiring-diagram-dr-z-400-thumpertalk-of-drz400-wiring-diagram.jpg
 
Test the coil side of the starter relay where it plugs in to confirm there is 12 volts there when you push the button (yellow/black to grey/black). Disconnect the relay from the battery and continuity test the point contact side to make sure there is zero resistance between the battery connection and starter. Starter motor is grounded to the motor but the grounding between the battery and the motor needs to also show zero resistance.

2008-drz-sm-wiring-diagram-dr-z-400-thumpertalk-of-drz400-wiring-diagram.jpg

Thanks guys, I'll be able to check tomorrow night and post an update.

Looks like the starter motor/relay is somehow connected to the tail running light...and my tail running light sometimes doesnt turn on. I suppose I could also check all the other devices that are connected to the starter relay via that diagram to track down where the issue is.

What is that pancake looking symbol coming out from the starter relay coil?
 
Ground cable to which? The starter motor or the switch? Theres only 1 wire going to the starter motor and I assume its power. Starter motor gets grounded by the engine block correct?
Check both ends of the ground cable to the battery and frame, that's the one I have seen loose more times than I can count. Starter motor will ground through its mount, it will not have a separate ground wire. Some bikes also have a ground cable between the engine and frame, I have never personally seen a problem with that one, but it's worth checking if it exists. If the main ground is loose or corroded, you may get enough contact to deal with light electrical loads, but under the high load of the starter, the resistance will cause a big voltage drop and the starter may not spin.

As for push starting, it's worth some practice. I have push started a standard car by myself (which was admittedly a bad idea) so anybody should be able to get a drz to bumpstart.
 
Side stand switch is not connected ...
All of your safety switches run through that "starter control and flasher relay" if you have no power to the plug on the starter relay when you push the starter button then that assembly would be highly suspect.

? what all has been changed or obsoleted? you didn't switch from incandescent bulbs to light emitting diodes anywhere did you?
 
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Check both ends of the ground cable to the battery and frame, that's the one I have seen loose more times than I can count. Starter motor will ground through its mount, it will not have a separate ground wire. Some bikes also have a ground cable between the engine and frame, I have never personally seen a problem with that one, but it's worth checking if it exists. If the main ground is loose or corroded, you may get enough contact to deal with light electrical loads, but under the high load of the starter, the resistance will cause a big voltage drop and the starter may not spin.

Will check this.

All of your safety switches run through that "starter control and flasher relay" if you have no power to the plug on the starter relay when you push the starter button then that assembly would be highly suspect.

? what all has been changed or obsoleted? you didn't switch from incandescent bulbs to light emitting diodes anywhere did you?

The safety stand switch wasnt enabled since the day I bought the bike 5 years ago, but I will check keep that in mind when troubleshooting. I think the clutch safety switch (required to start the bike) is disabled as well.

I have a different tail light/fender than stock. It looks like the previous owner spliced it in rather than using OEM connectors. I think this is a suspect as well.

I'll have more time to look at the bike tonight, I'll be able to troubleshoot further.
 
Extremely difficult to trouble-shoot a modified electrical system because now you don't even have a map to go by. You're going to have to buy a multi-meter, learn how to use it and spend a ton of time investigating what you have been left to work with.

It had a neutral safety cutout switch at one time too.
 
When working on frankenwired bikes, I usually cut out the trouble circuit and rewire. First put the bike in neutral and using a small jumper, jump the small + tab on the solenoid a few times to see if the starter and solenoid are working. The probably are, if so then rewiring is simple.

1) Hi power lead from +battery to starter solenoid (the big lug), another from the solenoid (the other big lug) to the +starter
2) Switched power (ignition on) to one wire on the starter switch (on right handlebar control), other side of start switch (on right handlebar control) to the small +terminal on your starter solenoid, the other small connection on the solenoid to ground. If the right control has a problem, get a cheap kill switch off Amazon.ca and use it as a start switch.
3) Ensure starter is grounded.

That's all you need to crank the bike. If you want to make it safe again, wire the switched+ to the neutral start switch then the kickstand then to the start switch.
 
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Being a Suzuki i would bet the issue is the clutch safety circuit. On any other brand of bike you can start in neutral with the clutch out but Suzuki's need the clutch pulled to start no mater what. If that circuit has a loose connection it will do what you are describing. Find the wires that used to go to the clutch switch and make sure they are connected together securely.

Sent from my SM-G935V using Tapatalk
 
Aren't safety features wonderful :LOL: nothing keeps you safer then not being able to go anywhere.
 
Aren't safety features wonderful :LOL: nothing keeps you safer then not being able to go anywhere.
Have you ever tried to start a bike in gear? Unless the stars align, I doubt it would even work the vast majority of the time. Assuming the starter has enough balls to spin the engine fast enough while accelerating the bike forward, the rider should be smart enough to let go as the bike jumps under them. I'm not even sure the clutch switch is a safety feature, it's just the lawyers running amok (the side stand switch I understand, we've all seen someone try to make a left turn with the stand down).
 
Remember when all it needed to kick the side stand up was a chunk of rubber bolted to the end of the thing.
 
Not sure if its relevant to DRZ's, but on the older GS's the solenoid of choice are the one's you find at Lowes and Home depot for lawn tractors. usually somewhere between $13 and $17.
 
So I checked the relay coils with the multimeter and at rest it is -12. When I press the starter, it goes to -12.20 and drops back down when I release it.

Is my relay supposed to click when I press the starter? It is not clicking but from what I remember about relays, it clicks.

Also there is a correlation between my tail light running light and the starter not working When the tail light is off, the starter definitely doesnt work. But when the tail light is on, the starter sometimes works.

Can someone interpret these results and suggest a next step?
 

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