Dialing in a 1981 GS1000L

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Greetings everyone.

I have a 1981 GS1000L that I am trying to get the carbs dialed in on, and could use some of the collective power of the group. Basically, I think I just need to get the Pilot Screws and float heights more accurately set. Here's what I've got so far:

1) Using the scanned images of the CV carbs from Basscliff (which are now linked on favorites), I set the floats at 23 mm, +/- a few tenths I suppose. However, if anyone has a photo of how they have actually measured their float height, I'd enjoy looking at it as I'm not entirely sure I'm measuring from the right spot on the float.

2) I've had the pilot screws set at 1.5 turns out, then 2.25, then 2.5, then 2.75, and finally 3.0. (The preset caps and the screws were removed for cleaning.)

All the rubber (o-rings and boots) have been replaced with new from stem to stern and within the each carb. The air cleaner is also new and oiled.

The only way I can get the bike to start and run is with the air box removed, the choke completely open, and a squirt of gas/starter fluid into each carb. But I have to keep the choke open most of the way, and if I add any throttle it dies--too much air I assume.

I am assuming that I don't have the pilot screws and/or the float heights close enough to get the bike started under normal conditions (with the airbox on and no starter fluid).

I'm open to any thoughts/suggestions that the above might stir up for anyone.

As usual, much thanks to the group and the site manager(s) for providing a place to go for help.

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I should also add that I pulled the pilot jets (the itty bitty tiny ones) and made sure they were clean.

Also, I checked all jets against the manual's specs when cleaning the carbs, and they are all the right numbers.

Thanks again.

[Nessism]

Minor differences in how the floats are set won't cause the problem you describe.

Maybe the carbs aren't getting enough gas? Did you try setting the petcock to Prime? Assuming you have, how about removing the floatbowl drains to see if all the carbs are filled with gas (catch the gas in something of course)? Another thing to do is check the voltage at the coils - you want 11 volts or more. Strange situation, but don't give up.

[tom203]

Yeah, make sure your petcock is supplying gas- this is a refurbished tank, right? - pull at least two carb drain screws and check for fuel ! Then, pull spark plug and observe spark. You replaced choke rod- is it working on all choke plungers? Gas plus air plus spark (at right time) , motor should fire! might run awful, but it should fire. Doublecheck spark plug wires to make sure they're on correct plugs.

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The bowls appear to be filling up fine. I've had to empty each bowl every time I made adjustments to the floats, and every time they seemed to be equally full.

I do have a replacement petcock from Pingel installed. However, I added an inline filter to capture some of the "rust dust" that might be lingering in the tank. I'm beginning to wonder if the filter is interferring with the fuel flow.

Concerning the coils/voltage, if the bike will start with the airbox removed and some starter fluid, would this indicate that the spark is sufficiently strong?

Reltated, the battery tests at 12.2V after sitting cold for a while. It's about three years old and sat completely idle for over two years. Might it be the weak link, or one of the weak links?

Finally, I think I've seen some conflicting information about the position of the Pilot screws on previous threads I've searched. 1.5 turns out, or 2.5 are what I've seen. Which is most accurate, or is something within that range ok?

Thanks again folks. Success is on the way!

[Nessism]

2.5 turns out is a good starting point, after that you tune them to achieve the highest idle speed.

BTW, do you have the idle set up using the main adjustment screw? If the idle speed is too low the bike won't want to run very well since there won't be enough air coming though.

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Got it running.

I reset the air screws to 2 turns out (from 3), and I raised the floats a little. I also discarded the fuel filter.

I also discovered that the idle screw was set too low, but got it adjusted after the bike started running and warmed up mostly.

The battery also was a weak link. I connected the battery to my car battery (with the car turned off), and the bike started. After setting the idle at 2k for a while, I turned off the bike and started it again, but the battery didn't seem to want to turn the engine over very much.

I just finished putting the acid in the new battery and I'm letting it sit for 60 minutes before charging (as per instructions).

After that it will be fine tuning. I'll have to adjust the pilot screws by ear at first, as my colourtune spark plug is buried in the new garage after our move to AL.

Thanks for all the input, and I'll keep the group posted with future progress.