Extremely difficult cold start

[Vdriveboater]

I've had my NTM (new to me) '94 XII with 45K miles for less than a week and have just replaced the spark plugs, but bike operation has not changed. Cold starting is tougher than any bike I've owned. The poor starter gets more wear and tear in one start session than two years of normal starting. It does best with the choke applied, and it turns over great (seller installed new battery and I keep it on a maintainer). After 10-15 tries, it starts to burble a bit like it wants to start, but it will take another 10-15 tries until it finally will stay running. Once running the choke needs to be partially applied for 3-4 minutes before it will stay running with no choke. Once warmed up it does have some kind of a miss at idle and low rpm with little load (and the rpms "hang on" for awhile, but once on the road cruising it is smooth and powerful. The seller claimed that he put new gas in it but it smells like it might have some old mixed in. If fuel quality was a problem I would assume it would have an impact at all engine temps. After riding a few miles and shutting it off, it starts immediately as soon as the starter is engaged. I would think that the carbs need a good cleaning, but I'm wondering if that could make it so hard starting when cold? I see from forum posts that the bike has a fuel pump (I don't think my '01 ZRX1200R does), but does it pump fuel only after it starts, or does it pump when the starter is engaged? But if the bike was running 24 hours ago, the carb bowls should still be full. Anyone who's experienced this or is familiar with the issue, please chime in!!

[Nails]

Search here for a switch to disable the starter motor. This lets you pump up the float bowls without cranking the engine. The pump clicks until the float bowls are filled. Then flip the switch and start the bike.
I would chunk some Seafoam in the gas. Better yet, do that after draining the tank and adding fresh gas. Maybe some water condensation?
I suspect that the carbs aren't up to snuff, such as the float bowls leaking overnight. I would loosen the float bowl drain plugs looking for dirt to run out and whether the float bowls are filling. Maybe a leaking drain gasket? You might want to measure the gas volume carefully, looking for one float bowl different from the rest.
There are posts about all of this in here.
These are just some cheap checks, off the top of my head. My crystal ball says that you'll soon experience the joy of removing the carbs.

[Vdriveboater]

Thanks Nails, I think I'll get the tank drained for starters. After thinking more about it, I have a feeling that the Pilot Jets are plugged. There is no gas leaking or gas odor, so I'm confident that the bowls are full. The pilot jets control the fuel from the carb to the engine at idle, so if they're not flowing enough gas to the combustion chambers, it's not gonna start. Once it finally does run and is warmed up, sometimes it wants to stall if a little throttle isn't applied when the RPMs finally come down, which seems like further evidence of insufficient fuel/pilot jet plugging. I believe the pilot jets have the smallest orifices of all the jets on these carbs, so it makes sense that they would be the ones most likely to get junked up. Removal of the carbs should be a fascinating adventure, only bested by the intense pleasure of reinstallation.

[Vdriveboater]

Just an update -- three of the four pilot jets were completely plugged. The one that wasn't plugged was in a carb the seller had replaced with one from a parts bike he bought. This is exactly what I was hoping to find, because it explains the almost impossible cold starting and close to stall condition for the first 5 minutes. The inside two carbs had covers that were quite rusted on the inside, whereas the outside chrome covers were fine. It seems that Keihin (or their cover supplier) did a bad job of plating, and I'm guessing that a previous owner let the bike sit for long periods in a humid environment causing condensation. The seller is sending me the two chrome covers (rust free) from the parts bike, along with the right chrome swingarm bolt cover that wasn't on the bike.

[GrandpaDenny]

Nah, only the outside covers are plated, the inside ones are plain.

[Nails]

After thinking more about it, I have a feeling that the Pilot Jets are plugged.

Nice guess.

[Vdriveboater]

As the saga continues, today I drilled/removed the "welch plugs" that cover the idle mixture screw heads. Turns out (no pun intended) that #1 and #2 were "buried", meaning they were screwed in as far as they would go, and the other two were backed out only 1.5 turns -- that'll maker her run lean for sure. According to the seller, the bike was originally sold in CA and he removed most of the emissions related garbage. The welch plugs appeared to be OEM or else someone did a perfect job of installing them. So I have to assume that Kaw messed up, unless Keihin supplied them that way per contract with Kaw. This is further reinforcement of what caused the bike to act like it was super lean at idle and didn't want to start when cold. Now I'm waiting for the Fedex package the seller claimed to ship with the two chrome carb covers from his parts bike to replace the rusty ones on my bike and then I can finish them up and reinstall. I didn't use the idle mixture screws that came with the rebuild kit because they required too much torque to install, instead I cleaned up the OEM screws, and I also reused the OEM floats.

[Nails]

I'm rather late to this party, but you'll want to check the float height. This is critical and can somehow change over time.

I don't think you said that these are genuine Kawa replacement carbs; and I seriously doubt anyone could sell a new Kawa with pilot jets bottomed out.

[Vdriveboater]

I have no idea if they were OEM or replacement carbs, but they look identical and of course are Keihin brand, and they are all similarly "aged".

[Nails]

Sounds like a PO error. In fairness, these jets are a PITA to adjust -- hard to keep track of the turn count. But replacing the plugs sounds silly.