1980 KZ1000 Classic with Fuel Injection that Stalls

Here's Davids bike.
She's a beauty.
Any thumbnail links to page with selectable detail and resolution for all.

Yep, I have but its a z650

Sid hasnt done the conversion yet but has the ms1 built (We got them in the same group buy) but I think he might go for a microsquirt now

How difficult was it to make the conversion? Any additional pics or advice would be great.

David

Hey Dave! Good to see you again!
(oops! HIJACK NOTICE)
Is that a wide-band O2 display on your left grip?
Just out of curiosity, are you running fuel only, or are you running fuel and spark?

Back to you, David (ddowns)I don't know of any Plug and Play way to make the early Kaw FI work to modern standards. Here's a list of what's wrong with it:
The injectors are wrong at both top and bottom to find an easy replacement.
The electronic box is actually analog based, not digital. This really complicates things, and makes "piggybacking" with another unit impossible.
The air flow meter is actually a flapper valve in the intake, which means that it impairs flow.

Here's the good about it:
If you have a control unit that works, it will work forever. (ps, My GPz11 box was working when I parked it, and the only reason I changed it was because MegaSquirt is so much fun to play with!)If the unit on your bike has run this long, I doubt if it is the problem.
The injectors can be cleaned and tuned up.
www.witchhunter.com/
Good reports about what they can do. It's the first place to start.
The factory FI is reasonably easy to tune with an adjustable fuel pressure regulator.
When the system works, it's stone-age reliable. And if it's still on your bike, and it's run this long, I'd keep it. Here's the deal: most guys have tossed theirs away, plugged the injector ports, and fitted carbs. So, 10 years from now, which Classics will bring top dollar? My bet is the ones w/factory FI still running.

So, here's my recommendation:
Have the injectors professionally cleaned.
Replace all fuel lines (make sure you use "fuel injection" hose on all pressurized lines!)and make it a point to change your fuel filter regularly.
Replace the fuel pump with an MSD #2225 (E-Bay, Jegs, Summit Racing)(<$100, usually). These are slightly smaller in diameter than the factory ones, and I've had to make a collar out of 1 1/2" wide weatherstripping, but all that did was make it quieter! Don't worry about overheating, the pump is cooled by the fuel going through.
Get an adjustable fuel pressure gauge. One of those cheap chinese ones that you can get off of e-bay will work, but don't trust the pressure gauge that comes with it! Factory pressure is 36# with the vacuum line detached. Lowering the pressure will lean it, raising the pressure with enrichen it. Just don't use this to cover up other problems.
But, considering what shape the rest of your bike is in, do what you can to keep the FI.

The bike was last registered in 2002 and rarely run. As a result, he could not get it to run right properly. I am hopeful that a thorough fuel cleaning and fuel line replacement will result in a running bike. I plan to start removing the fuel injectors this week and find replacements or have them refurbished.

If you price new replacement injectors you better be sitting down. IIRC they run about $300.00 each. If you are going to refurbish yours you might want to check with Russ Collins at RC Engineering. Since he has retired from drag racing he has been busy fooling with injectors for all kinds of race engines. I've often thought he might be the go to guy if my bike ever develops problems with the injectors.

I'll have a look if I can find any pics, the fuel side is relativly easy compared to the ignition. having all the hardware in place you should not have to many hurdles.
Yes that is a Wb02 on hte bars, its a tech edge 2E0 wbo2 and a palm pda are the way to go with tuning the VE table. You just log and put it through Megalod veiwer's ve analyser to get a target afr table, its great
Yes I am running fuel and igniton.

I was just looking at the RC eng. website and it looks like they offer an injector cleaning and testing service at a cost of $26.50 per injector. Pretty reasonable when compared to the cost of new ones. Here is a link to their site.
www.rceng.com/index.aspx

ddowns wrote:

New member of Zrider and KZ1000 Classic. Just purchased the bike with running problem. I was hoping someone could help me figure out which part is bad.

It seems to me that I am getting way too much fuel causing the engine to flood. I have heard that I may need a new computer, airflow meter, or cold start sensor. I tried to disconnect (also ground it) the cold start sensor and had the same result. If I shut off the fuel supply it seems the bike runs great until the fuel runs out. Could it be that my fuel pump is pushing too much fuel?

Does anyone live in Metro Atlanta that might be able to help me solve this problem? Perhaps you have the same bike.

Thanks,
David

Most EFI systems have a control loop that controls the richness by adjusting the "open time" (duty cycle) of the injectors. There is a temps emsor that adjusts the setting to "full rich" when the engine is cold, then transfers control to the 02 (oxygen sensor) loop after the engine warms up. The 02 loop adjusts richness based on the amount of unburned hydrocarbons in the exhaust stream.

If the engine is staying in "full rich" mode, it will run too rich after it warms up.

Another possibility: could you have a sticking injector that is staying open?

ddowns wrote:

Update: Today I replaced the battery and noticed hours later that the injectors are still hot (with ignition off) and the computer was hot as well. Obviously, the injectors are wide open and the only way I can cool them off is to disconnect the battery. Any thoughts on what is causing this problem?

Thanks,
David

Sounds like the integrated circuit that controls the injectors is hosed. That IC computer module would have four power transistors inside it used as switches to drive the four injector's coils. They are designed to only be ON a certain length of time, not all the time. If the module is turning them on permanently, they will dissipate a lot of power and get very hot. Sounds like the electronics are fried.

ddowns wrote:

The bike was last registered in 2002 and rarely run. As a result, he could not get it to run right properly. I am hopeful that a thorough fuel cleaning and fuel line replacement will result in a running bike. I plan to start removing the fuel injectors this week and find replacements or have them refurbished.

You may want to swap out the control module and see if that fixes it. Your injectors may be fine, based on the symptoms it sounds like the controller that drives them is not working.