TOPIC:

Alright, I've been browsing this forum for the past couple months trying to gather as much information as i could through the search function, but I've reached an impass and thought I should just ask for some advice on what to try next in order to get this bike running.

some background info; I picked up a 1980A1 KZ550 in september as a fixer up. Has 26.5k miles on the motor, and the PO had told me he had it running good last summer, but let it sit out through the nasty Pacific Northwest rain all year and it wouldn't start.

My first stop was a thorough carb cleaning. Pulled the carbs (TK22) and they had this white film looking stuff that coated the entire float bowl (almost looked like crystalized white varnish). After 2 weeks of scrubbing, 5 cans of carb cleaner, and a boiling of lemonjuice and water, They were looking respectable again. Ordered and installed new carb repair kits from z1 enterprises (www.z1enterprises.com/Carburetor-Rebuild...Z550-198083-476.aspx). I believe the mains were #92, and pilots #32.

I got the carbs back on the bike and currently have the air screws set at 2 1/8th out, allowing it to idle fine with the choke on. The second i try to take the choke off, it dies. with the choke on I can rev it about half throttle before it cuts out. There is no black smoke from the exhuast, and ive let it warm up 10 mins on choke before trying to turn it off, and it will not stay running. Even with gas, it will die.

The points are a little warn too, but I was able to adjust them to the correct (.14mm) gap, although I will need to recheck the 1/4 timing as i noticed that the 1 and 4 cylinder pipes were getting warm, but not as hot as the 2/3's. Take in mind, I am doing this all without the gas tank (as it is filled with rust and nasty red gum looking crap), The stock air box and exhuast are hooked up as well. I plan on ditching the stock exhaust eventually for inline baffles and chrome tips, but getting it running on stock settings is my first priority.

Is there anything that I am missing? What would the next logical step be? I hope I gave enough information to get started, and I'm eager for any and all opinions/advice! This is my first time inside carbs, or rebuilding a bike, so it's all new territory for me!

What are you using for air filtration?

I would check for:

1. Good battery voltage
2. Fat blue spark
3. close to battery voltage at the coils
4. Proper float level (clear tube method)
5. Clean fuel filter and good gas flow from tank to carbs

If all those are good, I would suggest turning air screws to run a little richer. If you are getting good spark, and it idles well on choke, but dies off choke, you are (most likely) running too lean!

EDIT: You can test the lean theory by partially obstructing the air filter. (ie cover with your hand, shove a towel in there, etc) If it runs better like this, thats your problem

Have you checked for vacuum leaks between the carbs and engine? TK-22 carb Idle Mixture adjustment screw is an Air Screw. So closing them will richen the mixture and opening them will lean it. 1 1/2 turns out from lightly seated is the starting point.
Thanks to member Loudhvx, here is his TK22 web site, full of info for you.
home.comcast.net/~loudgpz/GPZweb/TK22mainPage/TK22mainPage.html

Adding the url tags in the outgoing message box results in the link showing in the forum post as follows:

home.comcast.net/~loudgpz/GPZweb/TK22mainPage/TK22mainPage.html

Good Fortune!

Thanks Patton, I just copied and pasted the link, usually works fine.

2-1/8th is too far out. Further out makes it leaner. Turn in to 1-1/4 to make it richer.

The choke needs to stay on for quite a while on these TK-22 carbed bikes. I usually have to drive about a 1/2 mile in hot weather before the choke is completely off, if I don't let it warm up. In cold weather it may be a few miles.

Since you let it warm up 10 minutes, it sounds like your pilots are not working (but they are new), or your idle setting is simply set wrong. The choke also increases the throttle position, so when you turn the choke off, the throttle closes. You need to set the non-choke throttle stop (aka idle speed knob). It's the big knob in the middle of the rack. But you say that twisting the throttle won't even keep it running... so are you sure the throttle slides are actually opening when you twist the throttle? There are two cables so if they are swapped, it may not be opening the throttle. Use the big knob as a test for now.

Check my site that Motorhead linked to, and verify you have the choke parts in tact.

Also, check out the fast-idle modification. You may want to do that before fully reassembling the bike. It makes fine adjustments to the choke's throttle position accessible without taking the tank off.

There are many other possibilities, but you should start with checking the basics like making sure the throttle cables are actually operating the throttle.

650ed wrote: What are you using for air filtration?

The stock airbox and a clean air filter (OEM as far as i can tell)

I would check for:

1. Good battery voltage
2. Fat blue spark
3. close to battery voltage at the coils
4. Proper float level (clear tube method)
5. Clean fuel filter and good gas flow from tank to carbs

If all those are good, I would suggest turning air screws to run a little richer. If you are getting good spark, and it idles well on choke, but dies off choke, you are (most likely) running too lean!

EDIT: You can test the lean theory by partially obstructing the air filter. (ie cover with your hand, shove a towel in there, etc) If it runs better like this, thats your problem

The battery that came with was defunkt, I believe it had some voltage, but no cranking amps. I will double check today. Are there any direct OEM replacements like Yuasa? I tried looking on Rockymountainatv and Z1Enterprises, but no luck.

I was getting fat blue spark and about 12v at the coil. since the battery was of no use, ive been using a car charger set at 12v. is that a major no-no? Thanks for the tip on testing the leaness, I'll put a washrag in the box and see if I notice a difference. Was also going to spray some carb cleaner around the boots and look for leaks there.

As for the float and fuel mixture, I haven't checked the level yet but will do so today. I assumed that they were working properly because they were filling up, but I will double check with my Haynes. Loud, you suggested 1-1/4 for the air screw? I had previously tried that when i first put the new screws in, and I couldn't get it to fire at all. It only seemed to want to run past 2 turns out... the only thing that may be different is the "lightly seated" part. I may have been turning from a "moderate seated" position, so i'll play around and see if i can't make anything happen.

Thanks again for the help guys! I will report back later on with any updates!

alright, as per Loud's suggestion, I adjusted the Pilot screws to 1-1/4 and she now runs off choke! I ran into a new slight problem though, as I went to put in a FI Adjusting "knob", i was stumped as to what it was supposed to do. I come to realize after looking at the TK carb sight again, That little spring mounting plate right next to the knob is gone!

now, unless i hold the FI in the proper place, it will increase in idle to about 4k... going to have to think of a solution. anyone have some detailed pics of the Fast Idle screw and spring assembly as it should be?

Also, checked the battery. Its dead after being trickle charged for 3 days. going to need to find a replacment.

Does this help?

yup that's what i need Motorhead!

im gonna try and pick up a spring like from the hardware store and see if i can't fab something up. I pretty much need it constantly depressed though to get that erratic idle to go away. Leverage and angles were never my strong point, guess I get to learn something new today!