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Discussion Starter #1
I'm not a mechanic, but I can usually get something to work the way I need it to. Lol.

Well I got this Kawasaki 700ltd given to me to fix or scrap. I managed to repair the gas tank, remove the carbs, soak them till they were shiney and clean. After removing the air pollution bs off this thing and redoing the vaccume lines, I got this thing purring like a kitten. I now am having problems with the bike not revving up while riding. 1st gear screams, all power, shift to second and give her gas, she starts to sputter in half way and wants to die off. Clutch and rev motor and she will redline. Put in gear and will sputter in all gears but first.
I checked all the floats, needle valves, blew out the fuel lines in carb and is completely clean. Spark plugs were a little grimey, cleaned them checked gaps, and checked spark before replacing them. Has pressure in all cylinders. (If I sound dumb, sorry, I don't have all the right part names yet, self taught, dad wasn't there).
What am I missing? This bike is screaming at me to run! I need help here.
 

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Female Rider
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Did you take the air pollution bs stuff off and leave it off? If so that could be your problem. On most bikes just changing the pipes can lead to the need for the bike to be rejetted. Doing things to the "fuel system" often leads to lean conditions. Hopefully some of the mechanically minded folks can help you.
 

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ZAMM Fanatic
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As soon as you report removing "all that air pollution crap" you lose the attention of most professional motorcycle techs. Working properly it costs little or nothing in performance, and removing it often CAUSES the very types of drivability problems you now report.

A PROFESSIONAL mechanic will restore the "Pollution Control" equipment to it's as-new state, and THEN begin diagnosis. Bottom line; unless YOU are knowledgeable enough to diagnose the problem, then you are NOT knowledgeable enough to decide what equipment can be removed.

I'm sure this isn't the answer you wanted to hear, get mad at me if you like, but it's more than likely the reason your post hasn't garnered any lengthy, detailed, helpful responses from any of the retired mc techs who hang out on this forum. And there are several.

See that POS white Ninja I'm on? Ran a WHOLE lot better after I re-plumbed all the PCE "crap" the last owner removed, unhooked, plugged, or failed to keep in working order.
 

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Discussion Starter #4
I was told the vacume lines and the pollution unit was probably the problem. Well I could get some vacuum lines and make the unit part of the system again. It couldn't hurt to try. Thanks for the tip bud. I'll get on it this weekend and see what I can come up with.
 

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Just a guess, but it looks like a coasting valve (AKA deceleration enriching valve). As early as the early '80s, EPA regulations required the idle circuit to be leaned 'way down. That cut emissions, and the engine would still run just fine, BUT it was so lean that if you were cruising along and let off the throttle abruptly, the engine will make a loud "popping" sound like a backfire due to suddenly dropping back into the idle circuit. I think this is equivalent to detonation, which is pretty bad for the engine as well as annoyingly noisy--- though I could be wrong about that. (That's the reason for the "no engine braking" signs in some neighborhoods--- to get rid of the lean popping noise.)

The device works off the change in intake manifold vacuum when you close the throttle rapidly. I can't remember whether it restricts the air, holds the slide up, or (more likely) lets in more gas for a moment when you decelerate, though either way would probably eliminate the popping. When you remove the device, in addition to being illegal, at least in California, You remove part of the low speed function of the carburetor. Depending on the bike, and what the valve actually did, the effect might be negligable, or it might make it hard or impossible to start. That's why a bike shop will first put the device back on before they attempt any repairs--- in fact, they have to replace it, by law, before they let the bike leave the shop. I'd put it back on and see if your problems go away. It's hard to outsmart Japanese engineers.
 

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Discussion Starter #7
I replaced it, and solved my problems so far. Took her for a ride and she rode like a dream. Thanks for the help everybody, I'll post a pick of this ugly monster. Lol.
 

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Discussion Starter #10 (Edited)
84/85. Still working on title from friend.

Thinking about adding a riser and straight tbar. Then losing the seat, replace with a single, changing the rear fender, and adding side liscence plate and tail light. Kind of the bobber style, with the fat tank.
 
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