Dont start / Wont start

[fourqbt]

HELP.....!!!!!!!!

Bought a second hand GS500E, it had some faults, mainly the carb had seized butterflies and the choke and throttle cables were seized too. I freed the cables up with lots of lube and patience, replaced the throttle slider andtook the carbs off to give them a major clean.
Before I did this, the bike did start but very roughly and ran on one carb for a short time.
I cleaned every part of the carbs I could find, inside and out. Used an airline to clear any and all crud from everywhere. The things shine inside and out..!!
Stripped every jet, seat, seal ect from each carb being carefull not to mix them up and replaced the gently back into the correct locations using the manual as a backup guid for the process.
Yesterday I re-assembled everything on the bike to have her running, put the tank petcock into the ON possition, the secondry petcock to Prime, turned the engine over several times with NO sign of life. Checked the spark (excellent), Checked the battery (totally good charge), Checked for fuel flow.... not sure cos the plugs looked dry. Placed a small amount of fuel down the pots and she tried to fire. Several minutes later I tried again without putting gas in the pots and eventually she spluttered into life. Rough...?? thats not the word for it but as she warmed up, she got better and better until she ran like a dream.
Tried again by shutting down and re-starting... 1st turn of the engine she leaped into life and every time after that she just sprung straight into a sweet engine tone.
This morning I thought I would run her up and let her idle over for a while just to hear that great sound again................ NOTHING.....!!!!!
She WILL NOT fire up, put gas in the pots... nothing.... spray starter....nothing, booster cables incase the batt was flagging.... nothing.
Sparks great, some gas getting though but not enough I think...

ANY IDEAS PLEASE
Bike is a UK Stock bike with NO mods


Hi Guys, ye3s I am BACK.....

Story update:-

Removed carbs again, again, again..... still no joy. Checked valve clearances, yes there is a little drift there but nothing to worry about for a couple of years or more.
Checked first petcock, not good, slight weep on the "O"ring, replaced and re-assembled, no more leak... still no fire in the beast.
Removed tank and filled the carbs by hand, no throttle, choke at full, 20 seconds of cranking and she burst into life.
Put tank back on and she fired up but only for a brief time. Took inline filter out and this made her a little better but she still stalled out.
Again I primed the carbs by hand and she fired up almost straight away but died when using the throttle, she is almost there, I can almost smell success but I am still missing something.

Eventually I got her to tick over for about 20mins, reved her to 9,000rpm and as soon as I shut the throttle back, she died. Then started her again and the revs were up at 3,000rpm on idle, checked the cable routings (all fine and free) checked the choke for sticking and the throttle, all fee. fired her up and she was racing higher, checked the idle screw and brought her down to about 1,400 rpm where she sat nicely. Touched the throttle and she died instantly again.
Now she will start without throttle but runs for a short time and stalls out again.
What have I missed...??
Carb boots front and reas are fully seated, mixture screws are at 2.5 turns from dead, a little popping in the exhaust and airbox.

[NiceGuysFinishLast]

Did you have the kickstand up? It won't start in gear with the stand down, even with the clutch pulled in.

If the stand WAS up, check the clutch safety switch, it's two wires that are connected underneath the clutch, to prevent you from starting the bike without the clutch pulled in. If you search "Clutch switch" here, you should find pictures of it.

[Egaeus]

Did you have the kickstand up? It won't start in gear with the stand down, even with the clutch pulled in.

It won't crank with the kickstand down either. 

Let's start with the obvious: you did use the choke, right?

Did it even try to start with the starting fluid or did it do nothing?  If it didn't do anything, then I honestly don't know what could be causing it except compression.  Umm....Have you checked the valve clearance?  Compression?

I'd definitely check the fuel flow.  Take the line off the carb and aim it into a suitable container.  Then turn your petcock to PRI.  It should flow freely.  If it doesn't, check the filter in the tank (attached to the petcock).  If it's intact (it's tall and sticks up inside the tank), make sure it's not clogged.  If it's not intact, then you will probably need to clean the petcocks, replace your lines, remove any rust from your tank and line it.  Alternately, you could install filters on the lines coming from the tank.

Speaking of filters, do you have one on the fuel line(s).  If so, make sure it's not a car filter designed for use with pressurized fuel systems.  They are very good filters, but they are also very restrictive, and will not permit enough fuel to flow with our gravity-fed systems.

[trumpetguy]

Is the kill switch in RUN position?  I bumped mine once and it took forever for me to realize what was up (I normally never touch it).

[Egaeus]

Again, it won't crank when any of the safety switches are off. 

[fourqbt]

Again, it won't crank when any of the safety switches are off. 

All electrics are fine and yes amaizingly for me I had the kill swith in RUN, side stand both up and down, bike in neutral. Engine turns over lovely and a great spark. Starter fluid finally worked but ran for a brief few seconds then died out again.

[Egaeus]

Then it is a fuel issue. 

[fourqbt]

Then it is a fuel issue. 

Thanks Egaeus
But what else can I check or do. Th fuel flows like a river direct from the petcock to a clear jar (which I placed a secure lid on afterwards because I too have had a nasty shock when smoking near fuel fumes Whooooooosh)
I am going to try without the fuel filter tomorrow but dont hold out much hope. If I put mu hand over the carbs while cranking the engine it will splutter into life for a few moments but can not twist the throttle as it dies instantly when I do that.
However.... what else can I do or havent I done that will get the fuel flowing from the carbs to the engine..?

[Egaeus]

Did you take the jets out when you cleaned the carb?  The pilots are easily clogged.  You may not have gotten everything out. 

Try removing the jets and the emulsion tube (with the carbs apart, put a brass punch in the hole where the main jet comes out and hit it with your hand) and make sure it's all clean. 

Also, before you do that, make sure that fuel is actually flowing into the carbs.  With everything hooked up, put the petcock into PRI and make sure that fuel flows continuously out of the carb bowl.  Your floats may be stuck.  Mine did that, and I had to pry them out.

[starwalt]

Have you confirmed the routing of the hoses in THIS PAGE ?

You could very well have a condition imposed on you by a previous owner.

Egaeaus has got a good suggestion. The paths for the fuel are tiny and it could also be that some debris has shaken loose in this process. It is a shame you don't have a spare set of carbs to swap out.

I would also install an aftermarket filter in the lines from the tank to the fuel selector. It couldn't hurt.

[rob1bike]

You didnt loose the small oring when you cleaned the carbs ?

[MarkusN]

Definitely a fuel issue. Since fuel flows to the carbs, next thing is to check fuel level in the bowls, and if that's okay the jets and small ducts in the carb for a third time.

About the small o-ring rob mentions I'd worry once she runs. It has minor effect on starting behaviour.

Since covering the air filter helps, you seem to have a very lean condition. Probably clogged jets. What did you use to clean the carbs? If you don't have the proper tools you might want to consider to pay for an ultrasonic bath.

[rob1bike]

Oh yeah, its fuel! Was thing maybe poor vacuum

[fourqbt]

Did you take the jets out when you cleaned the carb?  The pilots are easily clogged.  You may not have gotten everything out. 

Try removing the jets and the emulsion tube (with the carbs apart, put a brass punch in the hole where the main jet comes out and hit it with your hand) and make sure it's all clean. 

Also, before you do that, make sure that fuel is actually flowing into the carbs.  With everything hooked up, put the petcock into PRI and make sure that fuel flows continuously out of the carb bowl.  Your floats may be stuck.  Mine did that, and I had to pry them out.

I will give it another go tomorrow, too late now. Will also double check the routing of the fuel lines as recomended.

Dont hold your breath but will post an update as soon as I have tried these things

[Mandres]

Yes, definitely check the float level first and foremost.  Did you adjust the mixture screws during your carb cleaning?  Are they set properly if so (2 1/2 turns out from bottom)? 

[fourqbt]

Yes, definitely check the float level first and foremost.  Did you adjust the mixture screws during your carb cleaning?  Are they set properly if so (2 1/2 turns out from bottom)? 

Hi Guys,

Well I wanted to spend the whole weekend on my carbs and lo.... work has pulled me out to go to FRANCE for some meetings and thats ripped a massive hole in my plans. Oh Well !!!! theres always next weekend.
BUT...... as promised.... I WILL UPDATE every one as soon as I get some work started on my GS Baby again.... (ps.. next project after "operation get it running" is complete, may be a fairing convert to a hybrid Bandit..?? not sure yet)

[scratch]

Set up the bike for storage so you wont have such a headache coming back.
http://gstwins.com/gsboard/index.php?topic=32266.0