help needed. wont start after working before

[Guest]

Hi all. I am having problems starting my bike and I need some help.
with full choke on, and the idle screw (the one between the carbs) all the way closed to the left(closed throttle plate?), my bike wants to start but it just keeps chugging away.
i have tried giving it a little throttle to help, but it instantly kills it.
i've tried it with the idle screw all the way open to the right and it doesnt even try to start. ive also tried no choke and to no avail
im believing that it is not getting enough air. what could be causing this?

i've tested the spark plugs by grounding it on the engine and watching the spark. all 4 are firing but doesn't seem strong as a car's spark. is this normal?
i've checked the float bowls and they have gas in them. no overflowing bowls into the air intake

this morning, i was able to start it and idle it. i played around with the idle screw to get it around 2k rpm. while i was getting my tools, the bike died and hasn't been able to start since.

some previous repairs:
i've done the coil relay mod, new used RR, new stator with sense wire relayed and also a carburetor rebuild with new o-rings




i desperately need some help figuring this out. its so frustrating.

[5150/gs]

We will need more info, Pipes pods?or stock?are float levels correct hight?did you dip the carbs?or just spray them out?Did you bench sync them on reassembly?What kind of carbs and bike?Is the petsock functioning propper?And that screw is just the idle screw,where are the Pilot screws set?and what main and pilot jets are in it?do they match the intake and exhaust setup as in stock? or aftermarket?Dynojet kit or no?Some of hat info will help us greatly to help you.

[5t341th]

this is all stock. floats level have been set. carbs were disassembled and dipped. i did bench sync. this is the stock BS32 carbs on a GS700e. petcock works fine(a few drops of gas comes out when i remove the tank, but i believe this is normal) pilot screws were played around with during this ordeal. started at 2 turns out, and currently at 4 turns out.

[5150/gs]

sounds about right so far, you are starting at a good baseline.If everything is clean and clear,float level propper and bench synced,and you have fuel and spark and valves been adjusted it should start good enuff to get a high rpm set on the screws and a sync done.if you unhook and suck on the vac line to petcok u get good fuel flow?A major air leak can cause too lean also.

[5150/gs]

spark should be Blue/white i believe.

[5150/gs]

Anyone else have ideas on this?

[lonerider00]

On my GS550, I rebuilt the petcock and noticed that the starter turning over the engine doesn't create enough vacuum on its own for it to operate. It took me a while to figure this out... So now, if I run it dry I need to disconnect the vacuum line from the carb and suck on it to prime the system to get started. This may not be your problem, but starting problems can be tricky. It might be a stupid question, but how's your air cleaner? Can you run on ether or starting fluid? Also, could you just have bad gas? (another problem I had... new gas mixed with a little bit of old gas. Ran great for a day, let it sit two days and couldn't get it started again... had to flush the whole system and start over).
Hope this helps and good luck to you

[svrider]

try swapping plugs out i have found the air cooled bikes seem to foul easier

[tom203]

After starting attempt, inspect spark plugs to see if they are dry or wet.Try to get idle stop screw back to original bench sync spot. Block your air filter opening with rag,or your hand, apply full "choke" and crank it. You might have clogged choke passages-did you blow out little hole at bottom of fuel bowl? -this feeds the enrichment system

[5t341th]

petcock seems to be in fine working order. i do not see leaks coming from it. it has worked before with no problems.
air filter is not stock. it seems PO put a drop in KN filter that replaces the stock sock. this doesnt seem to fit very well though.
how strong of a spark should the plugs be sparking? last time i checked on a car, the spark on the plugs were very powerful.
oh and for clarification, the idle screw, which way makes it closed? turning to the left correct?

[tom203]

Yeah, to the left-counterclockwise-closes throttle plates. You've done the coil relay mod, so a decent battery should give you an adequate spark during cranking.This seems a fuel problem; Put petcock in prime spot for 30 seconds, then crank it with "choke" applied. If it doesn't come to life, block air intake and recrank. pull plugs and inspect. Doublecheck that plug wires are on correct plugs.

[5t341th]

Another question. Does it matter which positive wire goes to a certain coil on the relay mod? It seems they can be swapped around without trouble.
My battery is good. I have 12.7v. I have a battery charger so it should be good.
When it was running good, I had a good 14.5v at idle.
Let me try what you said Tom203

[Killer2600]

Another question. Does it matter which positive wire goes to a certain coil on the relay mod? It seems they can be swapped around without trouble.
My battery is good. I have 12.7v. I have a battery charger so it should be good.
When it was running good, I had a good 14.5v at idle.
Let me try what you said Tom203

The coil relay mod has one +12v (positive) wire feeding both coils, if you split the feed into two it doesn't matter which one goes to which coil as they both carry the same +12v.

14.5v at idle is high but then again 2k rpm is a high idle, spec is in the 1,100 rpm area, +/- 100 I believe.

As for your starting troubles, have you tried half-choke and/or cracking the throttle while trying to start the bike?

[5t341th]

Yes of course. I am also noticing backfire coming out from the carbs. It makes a small puff sound when I am trying to start it. Any ideas what this could be?

[lonerider00]

if your getting backfire, it sounds to me like your plug wires are on wrong. when I first got my bike the PO had them all switched around the wrong way... he sold it to me as a non-runner... I got my Clymer manual, looked at the picture of the wires, switched them around, put gas in, and it fired the first try. That was a few years ago and I've more or less rebuilt it since then (not the engine except for a K&N OEM-replacement air cleaner and going through the carbs a couple times after a long sit; I want to put on a Dyna S when my coils finally burn out, but I've been waiting for a while and they just won't die...). Anyways, my point is, double check your plug wires and timing