1976 KZ 900 Engine Sputters after a mile

thetemples wrote:

Odd you say that.. I blew a fuse while out today and the wire was hot to the touch.. This is the same white, red striped wire you speak of? Is it possible I didn't have the fuse in tight? What do you mean make sure its tight?

now i gotts remember right...veg...in my mind i see: a sigle kinda thick white wire that ends in a male and runs under and by all the colored square connectors that plugs ( merges-with another male white) into a double female connector with clear flex plastic coming from a white also they are short and tucked in tight..i had to crimp the double female side a little cuase one of the males would start backing out(but stay in the plastic so looked pluged in and the bike would run like shit then take off then sputter- stall -start-ride okay again for a bit and repeat the bullshit...till i got my coils first and whites all properly and firmly connected....everyone else says...fuel ...which is what i thought mine was..filter..starving some other way....it was NOT...and i think you should listen to them first ...then me......peace

Update!


I unhooked the gas line from the carbs and put it into a milk jug and let it flow. Very slow to nothing coming out.

I opened the vent cap and no change. (side note: I cleaned out the channel for the cap and it was already clean)

I removed the petcock and it is a mess. It has glue all over the tubes from some type of repair that was attempted on it. It was mostly closed/clogged up and won't come off. I need a new petcock FOR SURE.

I'm excited!

Ok, so what petcock do I need? I have dual inputs to the carbs and the current petcock has one downward output. It is probably the wrong one because it shoots right down on the carb cone. Should it be sticking out to the side or facing the other side of the bike (parallel with floor?)

I will call Z1 today and see if they have something for me.

Thanks for diagnosing this for me. You guys are like rock stars.

thetemples wrote:

...removed the petcock and it is a mess. It has glue all over the tubes from some type of repair that was attempted on it. It was mostly closed/clogged up and won't come off. I need a new petcock FOR SURE...have dual inputs to the carbs and the current petcock has one downward output. It is probably the wrong one because it shoots right down on the carb cone. Should it be sticking out to the side or facing the other side of the bike (parallel with floor?)....

Don't give up too quick.
Acetone dissolves Kreem.

Thinking LTD (smaller fuel tank) petcock has one lateral and one downward petcock outlet nipple. Perhaps to allow sufficient petcock to frame clearance for the smaller tank. Standard model (larger tank) dual outlet petcock has both lateral nipples heading underneath tank.

The 76KZ900 manual petcock may sometimes be rehabilitated by disassembly and cleaning. Won't hurt to try. Don't lose the tiny spring located inside between the handle and tapered plastic cone. The cone is supposed to operate smoothly within the casing. If there's scouring or etching on the interfacing surfaces, it will probably leak. I've been unsuccessful trying to smooth out the interface -- tried fine valve grinding compound and some other types of grit pastes and polishes, but nothing worked.

Finally resorted to oem replacement -- wasn't cheap.

CAUTION! Gasoline dissolves some plastics -- so please be careful about putting gasoline into the common thin plastic milk jugs. And certainly don't store it there.

Good Luck!

Trying to determine if the problem is either fuel or electrically related can be a very time consuming chore.
I try by eliminating the easy stuff like fuel flow or lack of, and then start looking at all the electrical connections(bullet and square type).

For this style of engine to run you need:

1. Fuel (Clean gasoline and good fuel flow)
2. Air (Airfilter not dirty)
3. Compression (Valves properly adjusted)
4. Spark (Sparkplugs properly gapped, sparkplug wires and caps in good shape, coils not aged and breaking down).

If any of the four are not present the engine will not run as designed.

fyi- problem resolved.

New Petcock
New battery (<-- main issue) * I would charge a bad battery and after 10 minutes or less it was about dead