KZ1000 Hot Start Issue

Hi All! My '82 KZ1000 seems to starts OK, and idles great, but after it warms up it doesn't want to start again. Feels like it's not getting fuel. I have a new MotionPro carb synchronizer I just picked up, and will use that shortly, but I was wondering if anyone else had a similar issue? Also, I have a new Suzuki petcock from Z1 on it as all my KZ petcocks were leaklng. And my enricher only seems to pull out 1/8 inch total. Is that normal? Sorry for all the questions, any help is appreciated!

A hot start needs a less fuel/air (lean) ratio then an cold start (fat). Try a hot start with throttle fully open and enricher ciruit closed.

I'll try that. Thanks! How about that enricher knob? Like I said, it seems like it should pull out more than 1/8 or 1/4 inch.

Are the valve clearances in spec?

Haven't gotten that far yet.

mjudge wrote: Haven't gotten that far yet.

Hum, that's what I suspected. Not good. The valve clearance goes away with mileage and after awhile it's all gone and the valves hang open, particularly when the engine is hot. That's how valves get burned and cracked. I don't know for a fact that's what happening on this bike but I do know you need to tend to basic maintenance like this ASAP with any old bike purchase.

Describe the enricher issue more. The lever should be level when "off" and all the enricher collars should be down tight against the rubber cap. When you lift the enricher lever it should go all the way to about 45 degrees from horizontal and be lifting each enricher valve approx 8mm.
So the 1/8 in you mention, depending on if its level to start with when "closed" and only goes up 1/8 inch means the enricher is only partially opening making it difficult to start from cold.
If the lever is 22 deg (ish) when closed and only goes up 1/8 in then the enricher is always partially open. Making it easy to start from cold when the lever is lifted 1/8 in to fully open it but a bastard to start from hot as the enricher system is always partially open when you close it.

All that aside, ensure you do all the maintenance adjustments before using the bike for the reasons mentioned earlier in the thread,

Thanks guys. I've never done any valve work but I've done pretty much everything else, so I'll give it a try; the bike only has 10K on it so I was hoping valves wouldn't be an issue. The enricher is not a lever like on the KZ650, it's a knob you pull out horizontally, and mine only goes out about 1/8 or 1/4 inch. Don't have a picture or I'd attach it. Never had one like this.

You will need this.

www.kzrider.com/modules/ServiceManuals/K...Service%20Manual.pdf

mjudge wrote: Thanks guys. I've never done any valve work but I've done pretty much everything else, so I'll give it a try; the bike only has 10K on it so I was hoping valves wouldn't be an issue. The enricher is not a lever like on the KZ650, it's a knob you pull out horizontally, and mine only goes out about 1/8 or 1/4 inch. Don't have a picture or I'd attach it. Never had one like this.

If the engine only has 10k miles on it I would be very surprised if the valve clearances are the problem. Ed

That was my initial thought Ed. And I have the service manual but thank you! This quarantine has given me time to do stuff I don't usually have the time to do...

I'll admit that I don't have a ton of experience on anything but my KZ-1000, but after literally pouring over all the problem areas dealing with engine, carbs and ignition and poor running it's my personal opinion that the first jumping off point with any issue is valve adjustments regardless of mileage on the bike. Let's face it, unless you are the original owner of the bike you really have no clue what was done to it in the past. Once you are sure your valve adjustments are in spec you can move on to bigger and better things knowing at least the valve adjustment is good. After the valve adjustment the next important item to check is the spark advancer. I poo-pooed the suggestion to check mine when I first got the bike, but when I finally listened to those with more sense and knowledge than me sure enough the darn thing was super sticky. I also found one of the rubber pads was almost gone so I installed a new advancer. That one item made a huge change in the way my KZ-1000 ran.

So choke enrichers aside I think you simply must go thru the proper steps to identify a motor problem with these bikes. Certainly if the choke lever isn't functioning correctly it must be dealt with, but the OP would be very wise to go back to the beginning and start with a valve adjustment. If that doesn't help he can look at the next item on the list, but jumping around doesn't help in many instances.
Rick H.