Hard start, 4000 rpm idle, then dies. repeat.

[exdirtbiker]

79 GS1000L .
The bike had been starting instantly, smooth, and lifting the front wheel in 2nd gear until one carb started peeing on the floor. So I did the whole clean-up procedure.
I just just the freshly dipped-n-cleaned carbs back in.
new orings, boot orings, new gaskets and fuel tubes.
vacuum petcock seems to operate properly.
stock airbox, filter, exhaust. stock jets. valves adjusted last week.
Now that I cleaned everything "like new", it has a gremlin.
It only starts on full choke, idles high, then acts like it ran out of fuel.
wait a few secs... same thing. If I don't wait, it doesn't start.
It does the same thing with the tank removed and a funnel stuffed into end of fuel hose.
Please offer suggestions of where I screwed up.
and PLEASE PLEASE tell me I don't have to remove the #*& !!! rack from the bike.. again !!!

[koolaid_kid]

O.K., you don't.
But you might.
Have you checked out the petcock yet? Tried starting it with the petcock on PRI instead of ON? Checked the vacuum portion of the petcock?

[OLDENUFF]

You have a fuel delivery problem or your floats are set too low. That is why you have to wait in between startups. As your float bowls run empty you get an extreme lean condition which causes rpm's to go up. The choke gets fuel from the very bottom of the bowl. Check your float settings.

[exdirtbiker]

I know I set the floats to spec when I did the cleanup. Unless I used the wrong info...
In doing more research, I came across a few referances to "leave the vent tubes off".
Anyone recommend this ?

[exdirtbiker]

I would like to install 4 of these, then watch as I try to start it. ANyone know what size threads on my VM26 ?
I have lotsa fittings at work...

[Remington44-77]

Is the petcock hooked to the #3 carb? (third from left) Any thing else won't allow fuel to flow except on prime.

[exdirtbiker]

Is the petcock hooked to the #3 carb? (third from left) Any thing else won't allow fuel to flow except on prime.

yes. I even put finger on end of hose while cranking... I can feel the vac on it.

If I have to pull those @#$#% !!! carbs one more time, they are staying out until I find a 4:1 and pods.

Besides, I'm not sure the ol' rubber boots on the airbox are going to live through another R+R.

[koolaid_kid]

Not sure on the thread size, but the rule on the vent tubes is leave them on for a stock air box, leave them off for pods.

[exdirtbiker]

...If I have to pull those @#$#% !!! carbs one more time, they are staying out until I find a 4:1 and pods.

So that's the plan now, I'm giving up on riding this thing this year.
ANyone know what headers will fit the GS1000L ? Can I use pipes listed for an 850 ? 1100 ? years ?
Thanks.

[Guest]

since you have adjusted your valves and a carb tear down and clean, have you vacuum synched those carbs?? Oh, and about the vent tubes, it doesn't matter. I've run my VMs both with and without and there is no difference. To check your float level without pulling the carbs you can always drop one of the outer bowls and see how high the float has to go before the needle sets. Not an accurate measurement but it gives you a ball park, if you don't have a clear hose. There is an older thread about making up a clear hose but simply getting the right size hose then sanding the end to more of a point so it will jam in the drain hole nice and tight. I know people that use that and it works great. Also just as a note, the screw that holds your choke cable to the carb rack is exactly the correct size to fit in the carb drain hole, and a clear hose will fit perfectly on the end where the choke cable goes in

[Guest]

Is the petcock hooked to the #3 carb? (third from left) Any thing else won't allow fuel to flow except on prime.

Actually, not so. I had found my vacuum line attached to a fitting connected to my No. 2 sync port on my '79 GS1000E not long after I got it. The vacuum line to my number 3 carb wasn't even connected but the bike did run, actually pretty good until the hose fell off that vacuum sync port, and when it did that, shut off my fuel, I had to run it home on prime until I figured out what was going on.

[john82q]

exdirtbiker

Since you say it does the same thing with a funnel attached, its unlikely to be the petcock.

so needle and floats would be where to start.
from memory the float drain screws are 6mm x 1 (metric fine) but its probably best to take one with you and match it up, cause memory is a dodgy thing...

make up a a hose like pictured below and see the fuel levels in the bowl with the bike level. you only need one, just do each carb in turn.

Its very awkward but not impossible, to adjust float levels with the carbs on the bike.

[exdirtbiker]

Thanks everyone.
Still running on generator from Sandy. 8 days, no power. no heat until yesterday.
Lost a third of roof shingles, but no water damage.
I was lucky. 1 mile from me is the Mantoloking Bridge... now an inlet... ( google it )
so many people lost everything they ever owned.
So... The bike is going into winter hibernation, as I can't afford to replace the roof on my house.. ( $$$$$ )

[Steve]

make up a a hose like pictured below and see the fuel levels in the bowl with the bike level.

Mine is the second post "below" yours, and there is no picture.

I am guessing that you still have your thread-viewing options set to the default "newest post first", which makes if very hard to read a thread.

.