New to the forum, 1981 KZ440 LTD starting problems

Nebr_Rex wrote: Pull carbs and completely clean them. And get some new carb boots. You will need an impact driver or needle nose visegrips to remove the screws.
The screw head on the bottom of your pic is your idle mixture screw.
Looks like it has not been touched.

They don't seem to be pulling in air, but I was considering replacing them anyways, $21 a piece on partzilla though, ouch. That picture is from the first time I took them apart, before I touched the screws. They were both set to 3 and 1/4 turns (backed off of snug). I tried turning them in and starting the bike a couple of time until I got to 1 and 1/4 (backed off of snug), but it didn't help with the high idle.

Where are you finding the hoses for the carb? The ones I see on there are all obsolete.

Nebr_Rex wrote: Pull carbs and completely clean them. And get some new carb boots. You will need an impact driver or needle nose visegrips to remove the screws.
The screw head on the bottom of your pic is your idle mixture screw.
Looks like it has not been touched.

If you soak the carb holder screws with Kroil for a couple days and use a JIS screwdriver tip (or a modified Phillips) they will come out easily and will not be damaged. Ed

650ed wrote:

Nebr_Rex wrote: Pull carbs and completely clean them. And get some new carb boots. You will need an impact driver or needle nose visegrips to remove the screws.
The screw head on the bottom of your pic is your idle mixture screw.
Looks like it has not been touched.

If you soak the carb holder screws with Kroil for a couple days and use a JIS screwdriver tip (or a modified Phillips) they will come out easily and will not be damaged. Ed

I've got some deep creep and a cordless electric impact, so those screws don't scare me. I'm just pretty sure that there's no air leaking in through there. Tested three times, once with carb cleaner and twice with propane, couldn't find a leak. Worth replacing anyways?

Depending on how you tested the carb holders, you may want to give it one more try. When testing them, be sure to temporarily set the idle as low as possible without killing the engine. The lower the idle the better. This is because at very low idle not much air can pass through the slides and this creates higher vacuum within the carb holders. Spray carb cleaner around the mating surfaces between the carb holders and cylinder head. If they are leaky, this idle will drop and very likely stop the engine. That's what happened on mine when I needed to replace the holders.

Be sure to take a look at the following link regarding the cross head screws on the bike (and not just the ones on the carb holders). They are not Phillips. Ed

kzrider.com/forum/21-tools/532335-budget...ewdriver-tips#532335

Pull your carbs,remove float bowls and take a few pics.
Then check to make sure your pilot and main jets are the right size.

Nebr_Rex wrote: Pull your carbs,remove float bowls and take a few pics.
Then check to make sure your pilot and main jets are the right size.

Sorry it's taken so long to reply, I don't get too much time to wrench on the bike these days. So I popped them off and took a few pics, not sure of how to check the jet size, but I called the PO and he said he never changed them...







A little bit of crud in there, cleaned it out and re-installed the carbs, exact same issue. Any ideas?

I was concerned that the little orange plug next to the two main jets had fallen out.
Your pilot jet is underneath that plug.
You need some screwdrivers that fit the slots in the jets precisely.
Also apply a little downward pressure to avoid burgering them up.
Then clean all passages

Hey guys,

Where do you get those little rubber plugs? The ones that were in my 76 carbs were totally shrunk and I've been looking all over for what to replace them with. I picked up a couple of kits from Z1 but the rubber plugs were not included... Thanks!

Those plugs should have an O-ring on them to keep them snug fit. Was there suitable size o rings in the kits you got from Z1 ?