ready to toss a match in my fuel tank!

2low4NH wrote:

Okay i have an 83 kz550 that is running like smashed assholes.......

:lol: Dam! I almost spit coffee through my nose when I read that!

it was running good before i parked it. my plans were to bob the bike over the winter but the economy has me in a bad spot right now. the kid i bought it from rebuilt the motor (atleast he said he did) he also put these little stubby mufflers on the bike which make it sound like poop. could a lack of back pressure be hurting me?

2low4NH wrote:

...the gas should only be about 6 months old. there wasnt much fuel left in th ebike so i didnt bother with stabil. ...

You should have used the fuel stabilizer.
Fuel can go bad in as little as a month or so.
Fuel goes bad faster the higher the temperatures.
Small amounts of fuel go bad faster than larger amounts.

It's a vintage motorcycle. Assume the previous owner didn't properly care for the bike. Start at the tank & work your way towards the ignition system, checking & correcting each item as per the factory manual. Do not overlook the valve clearances & compression.

First thing to check is if there are disconnected vacuum lines from the emissions hardware.

I've seen that lots of time. The exhaust ports get a dose of fresh air from the air cut valve. The air cut valve is controlled by vacuum lines running back to the intake boots on cylinders 1 & 4.

If the pollution system is stil on the bike [ or even if it's not] check to see if there's an unhooked or broken vacuum line heading from the intake boots.

That will kill acceleration and make it backfire like crazy.

Hopefully it's just that simple...

Okay im a little hapier today! i worked on the bike a little bit i pulled the tank and ran it till the bowls were dry. checked all the electrical connections and such which all checked out. i played with the carbs a bit too! i took the only adjustment screws i could find and turned them all the way in then backed them out 2.5 turns. fired the bike up it ran better not great but better. i can actually run it down the road now but still bogs at 4-5k or if i jump on the throttle.

I do have a new question though. u said the emmisions part which im guessing kinda works like a pcv has a big hose off the airbox and is mounted under the tank! should have 2 vaccuum lines going to it right? i have one line coming off the 1st carb. all the rest of the carbs have plugs on the vaccuum ports. the 2nd and 3rd have ports on the bottom of the carb and the 4th has one on the top. these are both on the motor side of the carb. should i hook a 2nd line back up and lose te plug?
on the back side of the carbs between 1-2 theres a vaccuum line with a t coming off of it the same for 3-4 these dont go anywhere and are wide open where should those go?
the bike is still popping sounds like a shotgun going off when i let off the throttle. what do you think that points too? thanks for all the help guys.
i can get pictures if needed too.

Sounds lean. You might have a vacuum leak somewhere. Get the bike to idle and spray a mist of carb cleaner around the intake side of the carb mounts. You may locate the problem by hearing a rise in idle speed.

i know i have a leak on the 2 tees that tie 1-2 and 3-4 carbs together. the top of the t is open. just not sure where they should be tied in. can someone show me a picture of there carbs and vaccuum lines

Likely not exactly same carb but probably similar if fitted with Mikuni mechanical slide carbs.



Good Luck!

im looking for the ones off the boots. i dont have mikis on my bic im not sure what they are but very similar

Can you post a pic? It'd make it a lot easier to try to figure out what we're guessing about...

yeah i will get pics i gotta grab my camera after i get outta work.

it rained today so i didnt get any pics but i got another question. we have a kawi LTD750 sittin in the garage at my parents place.is that a KZ750 by chance? they look similar.