A Final Desperate Plea for Help

[Uruka]

I've posted on the board a few times asking for assistance in getting my GS650 to run. When I first got the thing I did a half assed job of cleaning the carbs, fixed the wiring, cleaned the plugs, and I was able to travel about 100 miles on it (with no air filters). It would die at over half throttle, I figured it was the carbs. I followed the carb cleanup tutorial to the letter. I bought pod filters, upped the jetting to 115, new battery, new rear shocks, rebuilt the front shocks. I painted the frame, tank, engine, and body work. I put alot of work into it. So every once in a while I would fiddle with it and try to get it running. I discovered that one of the connections on the ignitor was bad, I replaced the igitor, I have good spark, and still no go. The only way the bike will start is if I place my hand over the intake on the main carb. Can somebody help me???

[rphillips]

Not enough fuel going thru the starter (enrichning) circuit, or pilot circuit. Don't know of a main carb, they are all the same, except one has a vacuum for the petcock. I'm no expert, but I'd try a yardstick or thin plank so I could "choke all the carbs equally, at the same time. If you can get it to run long enough to warm up, the rpm should start to rise. back off on the choke to keep the rpm down. See if that does anything & holler back the results

[Uruka]

I took a couple of rulers and held them over one another to nearly completely cover the carbs and it would start, smoke a lot, and the RPMs would go really really high. After I removed the rulers the engine died.

[jjmaag]

You say engine work, have you checked the valve clearance? What is the compression? Are you absolutely sure the choke and idle mixture circuits are clean? Is the tank rusty inside giving you a bad fuel supply? Oxygen, fuel, and compression are all needed to run.

[Uruka]

You say engine work, have you checked the valve clearance? What is the compression? Are you absolutely sure the choke and idle mixture circuits are clean? Is the tank rusty inside giving you a bad fuel supply? Oxygen, fuel, and compression are all needed to run.

I'm using an auxiliary fuel supply while I'm working on the bike so the fuel is clean. I don't have the tool to check compression and I haven't had the head off to adjust valve clearance. I used Gumout and the special wire tool to clean the carbs, I sprayed Gumout into every passage but maybe that wasn't good enough?

[Big T]

I'm using an auxiliary fuel supply while I'm working on the bike so the fuel is clean. I don't have the tool to check compression and I haven't had the head off to adjust valve clearance. I used Gumout and the special wire tool to clean the carbs, I sprayed Gumout into every passage but maybe that wasn't good enough?

Correct - strip them and dip them

Read the Carb cleanup page and follow it completely

And adjust your valves - all other work is futile until you completely clean your carbs and set your valves

[oshanac]

Uruka-Even if you dip them, there MAY be some varnish/crap still hiiden in the smallest jets. If you take the jets out, hold them up to the light. You should be able to see all the way throught the jet holes and see a full circle of light. If you can see through them, you may need to use you wire tire to poke the debri out.

[jjmaag]

You have to remove the choke plunger and idle mixture screw and make sure you can spray cleaner and or compressed air thru all the passages from the bowl to the outlet in the carb. It is best to completely disassemble the carb, dip it in carb cleaner over night then spray cleaner and air thru the passages. The holes are very small and get varnish build up from old gas. It has to be perfectly clean to work right.

[Uruka]

Ok, I'm out to get the carb dip. I will go over these carbs like I'm performing brain surgery. Then I'll do the valves while the carbs are bathing.

I found a tool to check my compression, it was about 130 all around. I think the compression may be higher than that actually, the tool didn't thread in, it was just a rubber cone that you press into the plug holes.

I'll report back in a day or two. Thanks everyone.

[Big T]

130 cold is good with a rubber tip

[mark_vaughn]

The only way the bike will start is if I place my hand over the intake on the main carb. Can somebody help me???

You are using your hand as a choke. Reducing air flow thus creating a richer mix.
I agree with the others here, the problem is in the carbs.

[dirtyfingers]

While you have the carbs off, now is a good time to make sure your intake boots have a good seal. Get new o rings, gaskets, sealer, whatever... I'ts a pain to have to take them off again.

[Uruka]

While you have the carbs off, now is a good time to make sure your intake boots have a good seal. Get new o rings, gaskets, sealer, whatever... I'ts a pain to have to take them off again.

Brand new intake boots and o-rings all around.

I have the carbs soaking right now, well actually just one. That's all I can fit in that one gallon bucket. After I opened the carbs up I noticed that there was muck in them. The little filter screens had tarnish stuck to them and all kinds of good stuff. I guess the chem dip is a necessary procedure.

[salty_monk]

So is making sure the tank is clean & correct jetting with pod filters... you're lucky you didn't kill it running lean with stock jetting & no air filters for 100 miles!

Dan

[rphillips]

Like you said, like doing brain surgery.