Got my carbs in the mail, what needs done?

I just got my carburetors in the mail from ebay that were off of a 1981 KZ1000P. They were cleaned and put on my bike today and it started and ran. It runs very choppy though. My dad's 1981 KZ1000 had the stock carbs as well and we put those carbs on my bike (me and my dad own the same bike) and the bike ran wonderful. I put these new carburetors on the bike that were off of a KZ1000P, same year and it runs choppy. I know its nothing serious. What could be wrong when you revv the bike and it backfires and coughs alittle bit out of the intake side of the carbs and when it revvs up, It takes a long time for the RPMs to go back down again? Does it sound like they need synced? Is there a vacuum leak? my intake boots have no cracks in them. Note, i was running it without an airbox. But the carburetors off of my dad's bike worked fine without an airbox, so i know i don't need them. I have to get a camera and i will post pics of the bike. Sorry its taking me so long.

A couple of suggestions to help everyone know what you are working on. Go into your profile and add your bike yr/model at the bottome of your posts. I'm guessing that an '81 police bike would have BS34's as stock carbs, am I right? I'm not an expert on these carbs, but one will come along. The coughing through the intake sounds like timing or valve clearance, but if your dad's carbs run good on your bike, then that tends to rule that out. I think that a vavle clearance check might be in order just to rule that out. IIRC you just bought this bike, no? What happened to the stock carbs? Are the backfires thru the carbs, or exhaust? Someone here will get you straight, just be patient.

Ok, i edited my signature. My bike is a stock 1981 KZ1000LTD K model. The carburetors that i ordered were off of a stock 1981 KZ1000 police bike. When i revv the motor, it takes forever for the RPMs to come back down again. It also spits and coughs out of the intake side of the carburetors as you are revving it. I just want to know what the issue is. The carburetors have not been synced, but they were not pulled away from each other when they were cleaned. I ran the bike without an airbox just for testing which was not and issue with the carburetors that were off of my dad's stock 1981 KZ1000 LTD K model bike.

Thanks guys,
KT

Sounds like your new carbs will need cleaned and sync'd/ Wired George is who you need to talk to.

www.wgcarbs.com/forum/index.php

Good luck!
Steve

Imstall the air cleaner. Without the air cleaner you would have to jet real big to eliminate the popping.

Remove the cable to see if the bike will idle down. Roy

Kitten Tooth wrote:

...bike is a stock 1981 KZ1000LTD K model. The carburetors that i ordered were off of a stock 1981 KZ1000 police bike. When i rev the motor, it takes forever for the RPMs to come back down again. It also spits and coughs out of the intake side of the carburetors as you are revving it. I just want to know what the issue is. The carburetors have not been synced, but they were not pulled away from each other when they were cleaned. I ran the bike without an airbox just for testing which was not and issue with the carburetors that were off of my dad's stock 1981 KZ1000 LTD K model bike....

Perhaps pilot circuit is too lean.
Could try adjusting the pilot air screws.
Start by screwing them in clockwise until lightly seated, then back out 1.25 turns.

Screwing in enrichens pilot mixture.
Screwing out leans pilot mixture.

Good Fortune!

You need to make sure that all the float levels are exactly the same, and in spec. They change with age/wear, and are easy to correct.
DONT ASSUME they are correct. If they are off by more than 4-5mm, the bike will simply not run properly.

EVERYTHING from the air filter/box to the exhaust tip must be installed and AIR TIGHT, or nothing will work correctly.
Air leaks and parts missing causes the fuel map/curve of the carbs to change dramatically, essentially making the bike un-usable.

Make sure that the ignition advance mechanism is properly lubricated and returning to idle position.

All these things must be done as part of regular maintenence after many years of service/sitting.

GL!

Kitten Tooth wrote:

....They (the carburetors) were cleaned .....

Would you care to elaborate?

Are the new carbs the same type of carburetors as the LTD?
Or is one set the VM-type & the other CVs?

No airbox? And you say the bike ran fine w the other carbs & no airbox? Really?

The carburetors on a 81 police bike and on your 81LTD should be the same stile carb, with a couple of notable differences. The needles are quite a bit different and the jetting is different. The air box will make a huge difference in operation. First place to start is to see if the floats are set right. Than we go to the other stuff one by one. This will take a while so get a Thermos of coffee.

You guys have been very helpful, im going to check the pilot circuit screws to make sure they are right. I'm sure my uncle did that already but i bet they need some tuning. How do i check float levels? I know im kind of a pain in the ass, im sorry, im still learning. Thats why im here:) All i know is the carburetors were off of a stock 1981 KZ1000P. They were old and filthy. My uncle cleaned them. He said there was sand and shit in there and he sprayed carb cleaner through all of the openings to make sure that there were no blockages. The carbs are clean. VERY clean. The diaphrams were absolutely Perfect. I'll check the pilot screws. As soon as you guys let me know how to check the float levels, i'll do that too. I'll make sure that the throttle assy. is moving freely and smooth. I try the no cable thing too.

Thanks guys,
KT