TOPIC:

Hello all, I am new to the older bikes but I've raced motocross for many years. I had recieved an '85 Zn700 LTD from a buddy, but, unfortunately it was in pretty dismal condition. I've put quite a bit of work into acid washing and lining the tank as well as rebuilding the carbs from top to bottom.
To my questions at hand, the bike runs great but is a total dog in the top end. 1st gear is very strong however the bike bogs badly in higher gears anywhere over 4000rpm. And after having the bike running for a minute or so fuel starts dripping out of the "canister" from under the battery. It's not a small drip either, it is streaming out of there. I've checked the vacuum hose routing diagrams and I've got all the hoses hooked up properly. I say "canister" becuase that is what the vac. diagram on the fender calls it. Can I just rip it out and bypass it in some way? I opted to run individual pod filters on each carb becuase the airbox was trashed and I am pretty sure they are the cause of my bogging. Is there any rule-of-thumb to jet sizing for the carbs?

Thanks a lot guys,

Can you show some pics? We are not too good on ZN's but there are people here who own them. look in search for ZN 700 and find the person who owns one and pm them and they can help you. I will help you but I believe it is retro rice rocker

Yep retro rice rocker

Here is a simular diagram to the one on my bike's fender. The colors indicate were the shortened hoses hook up.

this is the vacuum re-routing I am proposing... Am I out to lunch here or will this work? I'll give it a try later, I don't forsee this but is there any possibility of damage to the motor by-passing this 'canister' thing?!?


Post edited by: Jae, at: 2007/04/07 12:59

Post edited by: Jae, at: 2007/04/07 13:00

That's the strangest looking setup. Wonder what the purpose it ? I notice in kawasaki.com parts diagrams that the bike has what looks like a regular petcock. What happens if you just clamp off the tubes from the tank and the gas flows from petcock to carbs to motor as with most of the bikes here

Ok...I think that crap is for emmissions control. I'll try what you mentioned later on today if I get a chance. Thanks man!

Hope it works for you but I got to warn you I have no idea what that stuff is or what it does.

I tied screwing with bypassing that 'canister' and now the bike won't run at all...Any other help would be hugely appreciated!

your most likely culprit is #4, the vapor/liquid seperator.
i would look to see if it is function properly.
( you will need a manual, there is a test in there for it)
next i would look at the return line and see if it is plugged.
you said you had to clean the tank.
did you kreem it?
you could have plugged the return line port without knowing it.
you will need a vacuum pump to be certain.
( there is another way to apply vacuum but it sounds to dirty to say )
either case, the charcoal canister is now shot because it has been fuel soaked so you need to try to find one.
lastly, disconnect all vacuum hoses and look for small black pellets to see if the canister has dissenigrated on the inside.

ain't emissions a bitch?

kawasakiman is right, the vapor seperator is prone to flooding, especially if the bike has been tipped over or the fuel tank over-filled.


The easy fix?
Yank all that emissions crap out of there!
I did that on my ZN700 and haven't looked back since.

could you please draw up an MS Paint diagram of what you did? I am lost here guys...