no crank, Iv been searching

[jeepin775]

Hey guys new to the forum, bought my first bike 3 weeks ago, a 2000 model. The bikes been fantastic for 3 weeks until yesterday. While riding the bike surged and bucked real hard then died. After that with the ignition on all lights on and everything the start switch does nothing. Iv been searching for common Gs500 no crank issues and have my clutch switch bypassed by p.o. I checked the fuse its good, when i jump the starter solenoid it cranks but no spark even with ignition on. Any pointers where to go next??

[cloud2692]

No spark with ignition on illd be looking at the ECU it could have also caused the symptoms that occurred before it died. My first thought was you ceased the motor until you said it cranked.

Sounds as if it could be a simple kill switch somewhere. Make sure it is in neutral to eliminate side stand kill switch and also pull apart your right control cluster and make sure that the switch isn't stuck.

[qcbaker]

No spark with ignition on illd be looking at the ECU it could have also caused the symptoms that occurred before it died. My first thought was you ceased the motor until you said it cranked.

The GS500 doesn't have an ECU, its carburetted.

But cloud said what I would initially check as well: side stand switch, killswitch, clutch safety switch.

[cloud2692]

By ECU I mean the CDI on these bikes (Under left side cover) however Suzuki reference it as an ECU on the diagram I have for some reason.

[qcbaker]

By ECU I mean the CDI on these bikes (Under left side cover) however Suzuki reference it as an ECU on the diagram I have for some reason.

Ahh, gotcha. I guess technically the CDI module is a unit that controls some aspect of the engine so I guess you could call it an "ECU" of sorts, but I don't think its what most people think of when you say "ECU".

Anyway, yeah if that has failed you'd get no spark no matter what you did... But I don't think that's a very common failure, is it?

[gregjet]

It is more than a cdi on the later models. Closer to a now not used term "transistor controlled ignition but it uses things like throttle position sensors etc to control spark and fuel flow to the engine ( see the bottom of the Carbs for the switch) so it is a ECU just not an efi unit ( electronic fuel injection). I don't know about the later ones than 2005 ( mine) but the earlier models have 2 reluctor spark timing lumps , instead of one, so it isn't super complex and fires both cyl from a single position sensor.
I would be looking for dud earths especially to the main switch or from the battery.
Don't forget the main fuse which is on the starter relay.

[jeepin775]

Alright so i have the bike in neutral AND kickstand up. Kill switch in either position doing nothing. I took the 2 screws out the bottom of the kill/start switch but couldnt take it all the way off because of the throttle being connected and me being frustrated SO i sprayed the shaZam! out of it with WD40 and put it back together to no avail. I checked continuity on that diode both tabs have about 100k resistance to the middle terminal idk if thats how it should be?? Thanks for the replys so far hopefull get this old girl on the road again soon. Main fuse is good also. ill try and hunt down some grounds also.

[qcbaker]

It is more than a cdi on the later models. Closer to a now not used term "transistor controlled ignition but it uses things like throttle position sensors etc to control spark and fuel flow to the engine ( see the bottom of the Carbs for the switch) so it is a ECU just not an efi unit ( electronic fuel injection). I don't know about the later ones than 2005 ( mine) but the earlier models have 2 reluctor spark timing lumps , instead of one, so it isn't super complex and fires both cyl from a single position sensor.

I was not aware the CDI controlled fuel flow... Its a carburetted bike, fuel flow is controlled by the the carberetor, is it not? I thought the CDI (even the later models with the TPS) just controlled ignition timing. How does the CDI control fuel flow? Not being sarcastic, just genuinely curious.

Anyway, OP, just so I understand, when you hit the starter button literally nothing happens, right? Like, the starter motor doesn't crank at all? Sounds to me like the killswitch has failed. Maybe replace the right hand control?

[The Buddha]

CDI or TCI - on a GS does not touch fuel.
Spark timing and advance only.
Those SS and clutch interlocks and what not tie into it
Cool.
Buddha.

[J_Walker]

are you sure its not the switch inside the handlebar?

[gregjet]

`It is more than a simple set of CDI's. Although there is two reluctors it is a single unit electronic control so there is more happening than a simple set of capacitive discharge curcuits. There is a TPS that influences the spark. THat seems to me to make it an electronic contol unit rather than CDI.  The 2 signals from the reluctor are fed from a single pickup to the unit and the unit decides which plug to fire on ALTERNATE strokes ( unless there is a waste spark which is possible. This I need to be informed on). The reluctors alone point to a TCI unit rather than CDI.

[jeepin775]

Alright team, last week after poking around the wiring for a while my bike randomly turned on! Everything was good and operated exactly as when I bought it. Then today I'm going to leave the store and the bike bucks and surges. I pull the clutch in and start reving the bike and it comes back to life. Another 100 yards down the road same bucking and the bike dies. I pull into a parking lot and attempt to start the bike. At first no crank when I push the start button. Then it starts turning over and the bike would run for a quarter of a second then bog and die. A few times I was able to rev the bike as soon as it started and then she would sound and run fine but when I got off the throttle it would drop to idle as usual then bog and die. Like spark is getting cut? After a few times like this the bike would only start if I rolled it around, not rolling start I did this all in neutral. The bike would then run and then the second I dropped in gear it died. Did this maybe 2-3 times. Now it's just no crank when I push the start butto. I'm at a serious loss and currently my bike is stuck in a parking lot. Thank you for any help

[jeepin775]

**UPDATE**
So my bike sat in a parking lot for the last few days, I managed to get the bike to start by jumping the starter relay. This confuses me, before it wouldnt start like that. So I let the bike idle and everything seems normal. I ride the bike about 2 miles and while im riding the bike bucked and surged and I THINK it was the bike cutting spark. I would immediately pull the clutch and rev the bike pretty hard and it would be good another 100 fee, then the same thing. This happened maybe 2-3 times then the bike just died I wasnt able to rev it out. After that the start switched worked and the bike would kick on for a second or 2 then it dies, after a few of those the start switched stoped working. Now I'm back to having a bike that the start switch does nothing.....

[qcbaker]

I would maybe look into replacing the pulse signal generator or ignition coils. Other people have had problems where they lose spark once the engine warms up due to some problem with one or both of those components. Maybe Buddha or others can give you more info on exactly why that might happen, as its a bit out of my range on knowledge.

[jeepin775]

Sorry I'm pretty new to bikes, what's a repudible place to buy these parts from?

[qcbaker]

http://www.bikebandit.com/oem-parts

http://www.partzilla.com/

And I wouldn't call it "reputable" but eBay is always worth a shot too.