1982 KZ650 cranks but won't start

LOL, I've done that on Keihin carbs before, back when I was in school. No, they were getting plenty of gas into the bowls, so I figured the float needles were okay, so I didn't pull them. One thing I did notice that I thought was kinda weird was that the pilot jets had these little metal plug like things in them with an o-ring. I've never seen anything like that before. I work on mainly Harley's, though, and I don't know much about metrics.

yeah the best i can tell that plug really is useless these carbs are pretty simplehave you tried to spray a little starting fluid in it

No, I don't have any. I just put my daughter to bed, so I'm gonna go back out and mess with it. Clean and gap the plugs, and generally go over everything I touched earlier. Worst case, I guess I just pull the float bowls again and make sure nothing got fudged up. What would happen if I pulled those little pilot plugs out?

i have taken them out before there is nothing to them just an aluminum plug with a rubber o ring on them not sure why there there but these a big hole with them out so im sure they need to be there

yeah, but they cover the pilot jet, right? Anyways, I just went out, cleaned the old plugs and put them back in, in case there was something wrong with the new ones. I also checked over the carb and the throttle cable, and I found that the throttle was stuck about halfway opened. I could reach in and puch the throttle closed at the carb, but it won't snap back at the throttle. I also found that the plug coming off of the timing plate wasn't connected all the way, but the terminals were still making contact. Anyways, I got the throttle plates closed and cleaned/connected the plug, and I got it to fire up, but now, it will only run with the choke out, and it dies if I even give it the slightest bit of throttle. I got it to slowly rev up to about 5000 RPM once, but it was making a really terrible clatter. Do you think maybe something with the cam chain or gears. I don't want to tear into the motor until I at least have gaskets to put it all back together, so I'm just gonna absorb a little feedback for right now.

Sounds like you have a few issues.. It is definitely running lean if you can only fire with the choke engaged..
I would check your manifold between the carbs and engine to make sure everything is tight and crack free.. An airleak there will cause issues..

Is the gas new? Some of these reformulated oxidized mixtures sour pretty fast and if it has ethanol you might also have collected some water.

To start I would pull the carbs and make sure all the channels are clear and while they are out pull the throttle cable and lube it using the foil funnel method.

Just my .02..

If the carbs aren't closing when you let off the throttle I would start there. Finding and fixing that may solve the other problems. You may have 1 carb that is not functioning properly making the whole engine run poorly. In any event, the throttle problem will need to be corrected, so I'd fix that first and see what happens. Ed

Your carbs are still VERY dirty and gummed up. If it only runs on full choke then the pilot circuits are still clogged. I know yo think you cleaned everything but you have not.

well, I know for certain that the jets are clean, but the passages may still be clogged. I drained the tank and put fresh gas in, so that shouldn't be it. The carbs are tight in the manifold, no leaks. I found that the throttle cable is broken, but it's only the housing and only affects free play. It's at the threaded part where it connects to the controls, and it's broken so that it's at full slack, so it's not tight at all, and there's tons of free play. I guess I'll start by ordering a new cable, and while I'm waiting for it to get here, I'll pull the carbs back off and soak them and find out why the throttle plates stick open. I'll post back tpnight after I get home from work and let you know what I find.

I also, in the whole process of cleaning and trying to get this thing running, replaced the stock airbox with the pod filters. I read a lot about it, and most people advised against it, but I really wanted to try it out. I also read that without pipes and jetting, it wouldn't do much in the way of performance. Would that maybe lean it out too much? Maybe when I have the carbs off, I should jet it. I plan on putting an exhaust on as soon as I can afford it. What do you suggest as a basis for jetting with the setup I have now?

One more thing is, the more I look at them, I think I have carbs from a KZ750. Is this even possible? Are they really any different? I looked on ebay for KZ650 carbs, and they look nothing like what I have. So, I searched for KZ750 carbs, and they look exactly like what I have. I'll go take some pictures and post them...

mccormack090305 wrote:

I also, in the whole process of cleaning and trying to get this thing running, replaced the stock airbox with the pod filters. I read a lot about it, and most people advised against it, but I really wanted to try it out. I also read that without pipes and jetting, it wouldn't do much in the way of performance. Would that maybe lean it out too much? Maybe when I have the carbs off, I should jet it. I plan on putting an exhaust on as soon as I can afford it. What do you suggest as a basis for jetting with the setup I have now?

If you put pods on you definitely need to rejet the carbs. The intake on these bikes effects the jetting requirements WAY more than the exhaust does. On my old 81 kz650 (mikuni vm24 carbs for reference) with the airbox and stock exhaust I was running 102 mains and 15 pilots, when I switched to pods (still running stock exhaust) I had to bump those up to 112.5 mains and 17.5 pilots, so that's 4 steps larger main jets and one step larger pilot jet.

In 82 I'm pretty sure you've got the Kienen carbs, so my jet figures won't help you any, and I don't know anything about those later year carbs to suggest jetting changes, but you definitely have to rejet that.