Running on cylinders 1 and 4, spark but no fuel

I recently purchased my first FZ1 (blue 05); been a long-time fan and came across a deal that would allow me to scratch that itch I've always had! I'm excited to get her up and running and want to thank you in advance for any suggestions or insight you may have. On to the issue -
The bike had sat for a few years and I bought it hoping to clean the fuel system and get it up and going. I pulled the carbs cleaned them out, flushed the tank and put new 91 in. It's now back together and running, but only on cylinders 1 and 4. When i found the cold pipes on 2 &3 i jumped to the conclusion that the coil was bad. $20 later I have a used coil off eBay but with the same result. I've checked the new coil and it is providing a blue spark on both cylinders. So what i thought was a spark issue must have been a fuel issue all along. I have opened the float drains on the carbs and while 2 is getting a steady stream, carb 3 is dry. I have pulled the slides out of the tops of the carbs and sprayed carb cleaner through the main jet hoping that if it's a stuck float it might just knock it loose and start supplying fuel. No luck so far. While it sounds like the carbs will be coming out again I want to pick your brains and see if someone might be able to suggest something i have yet to try prior to yanking them off again.
 
Sounds like you said the carbs [without seeing the bike] need to be taken out and cleaned properly , might be worth buying some new main jets while your at it. as they can be a bugger to clean well without damaging them
 
Hi
As you have already said the carbs will need to come off again , i have just done some on an r6 that's been sat outside for 3 years , as the fuel goes off and gums the jets and passages up you really have to be quite methodical with them , I find vinegar is good for soaking parts in for breaking the crud down , use a thin piece of wire and clean every hole in the jets . do one carb at a time so you don't mix and match parts , make sure you pay attention to the float valves too taking out the needle valves and checking fuel passages
Good luck
 
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Thanks for the suggestions. Here's where I am on it. Replaced carbs with a used but clean set off ebay. checked thuroughly before installing. No change, still only 1 and 4 running, 2 and 3 cold. The irony is too great to continue thinking it's fuel. Bowls all drain fuel when opened. Ecu? Compression? Valves?
 
As Delbert said, change the plugs. I had the same issue when I had my 01' way back when. It drove me crazy trying to figure out why it was running on only 3 cylinders. I had removed the plug and checked for spark and it looked good so I re-installed it. After not being able to figure out the issue, I trailered it up to Ivan's and in ten minutes he found the problem. Same plug I had removed had a hairline fracture in the porcelain and while it showed spark when removed with the tip close to ground, when installed in the cylinder, it was arcing back to the head. He changed the plug and I was on my merry way after missing out on two weeks riding trying to troubleshoot the issue. I agree with Delbert. Replace the plugs with new ones. They are inexpensive and this way you will start out on a fresh set in any case.
 
I'm reviving a 2001 FZ1 with dirty carbs and other issues from sitting awhile. I've done this before, and there are always gremlins, but to minimize them as much as possible, I always put in new spark plugs. Oil and filter change. New air filter. Clean and double check the carbs along with carb rebuild kits to refresh the gaskets. Petcock rebuild kit. Empty the fuel tank and check inside. If it's not clean and shiny inside, I'll install an inline fuel filter. New battery. Check fork seals. After that, it's tires, chain, and sprockets as needed, which is usually always.

My daily driver and my current project. This one is getting everything mentioned up there as well as new Racetech fork springs and an IVANS jet kit.
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Check the plug wire resistance to see if there is something going on there?

Maybe try wire from 2 or 3 to see if 1/4 changes?

Adam
 
If you swapped in a different set of carbs and you're still not firing on #2 and #3, then we can 99% assume it's not a fueling issue.
With that in mind, and knowing you already replaced a coil, I'd start swapping coil parts and spark plug wires to the other cylinders, good to bad, and bad to good.
That will tell you if it's anything in your coil wiring or plug wires. I'm also assuming you have new spark plugs across the board.

Beyond that, I think I'd be looking at a compression test and hoping you don't have a valve or head or head gasket issue. Good luck!
 
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Carbs need a thorough sonic cleaning. Just spraying with carb cleaner is not enough. Other things to check. Condition of the boots, diaphragm, any rubber seals and vacuum hose's
 
Thanks for the suggestions. Here's where I am on it. Replaced carbs with a used but clean set off ebay. checked thuroughly before installing. No change, still only 1 and 4 running, 2 and 3 cold. The irony is too great to continue thinking it's fuel. Bowls all drain fuel when opened. Ecu? Compression? Valves?

Well? Did you ever figure this problem out This place is dead enough w/ out you leaving us hanging
 
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