Full throttle and not idling

[chuck hahn]

Just realised its a 450..so two carbs..but you can still do a water test of the floats and needles. I use this as a test because its not gas for 1 thing, and it still checks to see the flow rate and if the needles are shutting off and opening up at the least.

[gs11ezrydr]

Among everything else suggested ,might want to check the carb bowl vents, and the fuel tank venting, (atmospheric) Crack open the gas cap, not sure where the 450's carb bowl vent tubes are located or how the fuel tank vents, You stated that it was running properly before shimming and since you had the tank off shimming the valves may be poss. that you pinched a vent hose, would have the same effect, (starvation) run a little while, slowly refill, restart then repeat itself.

[chuck hahn]

Fuel cap is vented via a small tunnel milled into the base metal below the chromed cover. the best way to be sure it is clean is to remove the black plastic cap inside, then the brown kidney bean shaped thing with the big ball bearing comes out...be carefull because theres another smaller BB underneath. Pay attention to the order they go in too.

Once its all apart youll see a hole there..blow some carb spray and compressed air in there to clear the vent passage way.

[Swim_fan02]

So I went through all the topics you guys suggested and to no avail. She will start after been sitting and will stay running as long as I keep the throttle at about 3,000 rpms. If I let it idle back down it will stall out and not start again. Like it's getting flooded. I did quite a bit of research on the internet about the mikuni bs34 and found that there should be a rubber plug over the pilot jets. Is this correct because I don't have any rubber plugs in my carbs.

[rustybronco]

Anybody wanna chime in? She starts after sitting for a little bit and idles for a minute then stalls out and won't start again. Plugs are both wet but no backfiring when she starts.

Chiming in.

Sounds like she's flooding out.

Have you taken the carbs apart yet and cleaned them?

So I went through all the topics you guys suggested and to no avail. She will start after been sitting and will stay running as long as I keep the throttle at about 3,000 rpms. If I let it idle back down it will stall out and not start again. Like it's getting flooded.

[Swim_fan02]

Chiming in.

Sounds like she's flooding out.

Have you taken the carbs apart yet and cleaned them?

Yes I did. Multiple times. Lol. Check your inbox rusty.

[rustybronco]

I did check it and the reason for my responding.

Your carbs still aren't right in my humble opinion.

You need to make an adapter to use in place of a carb drain screw, then connect a piece of clear tubing up to that adapter and hold it along side the float bowls, while the engine is running so as to be able to check 'wet' fuel level's on each carb.

[JTGS850GL]

It's either rich or lean.

Rich:
Do you smell gas in the airbox? Could be a stuck or leaking float.

Lean:
Could you have pinched the fuel or vacuum line going to the petcock when you reinstalled the tank?

[Swim_fan02]

I'm waiting on all brand new o-rings from cycleorings just to rule out anything inside leaking. But as far as the plug goes on the pilot jet. Any insight there. Like I said there was never one in there when I took them apart. EVER.

[Swim_fan02]

It's either rich or lean.

Rich:
Do you smell gas in the airbox? Could be a stuck or leaking float.

Lean:
Could you have pinched the fuel or vacuum line going to the petcock when you reinstalled the tank?

I could smell a little gas in the airbox but it wasn't an overwhelming smell and no the vacuum line is not pinched. I've also tried the starting fluid spray check for any leaks. I won't be tinkering wth it today because it decided to snow outside last night and get ridiculously cold out. Don't really feel like turning on the heater.

[rustybronco]

But as far as the plug goes on the pilot jet.

There isn't supposed to be a plug on the pilot jet. If there was it wouldn't be able to draw fuel. Do you mean over the fuel mixture screw?

[Swim_fan02]

There isn't supposed to be a plug on the pilot jet. If there was it wouldn't be able to draw fuel. Do you mean over the fuel mixture screw?

No. I read somewhere(can't remember exactly where for the life of me) that there was a plug the went on the pilot jets in the float bowl on the mikuni bs34 carbs. May not be relevant to our bikes but I just wanted to make sure.

[JTGS850GL]

No plug on that year/model.

[Swim_fan02]

No plug on that year/model.

Thank you. That's what I was looking for