hard cold start

Can anyone send me in the right direction for my problem?

81 kz305 ltd.
problem is when ever i try and start the thing cold it takes a long time. it sounds like it wants to fire up but doesnt. i havent looked at the plugs or timing yet and only because the bike seems to run great once i get it going. i adjusted the choke a while ago but i adjusted it so it gives way too much throttle ( another story ) and havent adjusted it back yet. once i do get the bike started i can use the choke to keep the idle higher to warm up the engine.

seems to want to fire more when the choke is off which makes me think its not a fuel issue. the PO did put 91 octane in it before he delivered it, wish he didnt as it doesnt need 91 at all, wondering if that could cause a hard cold start?

You should start by checking for vacuum leaks around the carb holder boots. If they're leaking the bike will take a while to warm up and sometimes not want to run. I would also check the condition of your battery

As the choke system is designed to function when the carb slides are closed completely down, should not touch the throttle grip when attempting to start a cold engine.

Good Fortune!

carb holders are new but i'll check for leaks anyways. i recently topped up the battery and also use a tender at night.

and like i said, the bike wants to start with the choke off rather than on. if i try to start it with it on then try again with it off it almost fires up.

If not already done, may help to review pages 34~35 and 62~63 in the the owner's manual (here's a free download):

www.kaseydavis.com/1987KZ305LTD.pdf

Good Fortune!

its about 20 degrees Celsius today and it fired right up. checked plugs, they look perfect after a ride.

so after some more work on the bike ive noticed that the fuel filter seems to drain most of the fuel in to what im assuming is the carbs when it sits for a day or two. im not sure if this is normal. ive read a lot of guys will shut the petcock off a few blocks before they reach their destination to make sure theres no fuel left in the lines but ive never done this. is this something i should be doing? also noticed that it takes a while for the filter to fill up with fuel once opened. i know the petcock works, i removed the fuel line and fuel comes out when on and stops when off.

also i dont know if this is just coincidence but i noticed on of the plug wire ends came off while i was looking at the fuel filter so i re installed it and the bike seemed to fire right up. im not sure if this is even possible to be the cause as the bike runs fine once i do get it going but maybe this is my problem? im going to to be riding it to work tomorrow for the first time and im hoping the thing starts easily in the morning.

The plug wire is not uncommon. You can cut off an inch or so of the spark plug wire and re-install the boot (assuming you have the screw on spark plug boots) to get a good connection. This is something that is easy and free.
Good luck going to work. Been there, done that so I usually choose a non-critical day to test my luck.

I'd cut about 3/16"-1/4" of the sparkplug wire ends & screw the caps back on. you can also by using a multimeter set on ohms, to test the sparkplug caps. They should read at least 5000 ohms, and heat, and vibration can cause them to fail. New caps are available at www.z1enterprises.

If you are not familiar with multimeter operation, watch this video:
The best multimeter tutorial

im a licensed automotive tech, i can use a multi meter, thanks for the info though i'll test them tomorrow. as for cutting some wire off, they seem to be at their shortest possible length already so i dont think i want to do that. they are the screw on style, i just screwed it back on, i noticed this one was very loose since owning the bike but never looked into it. i also assume the wire is part of the coil and cant be bought separate?

anyone have any info on the fuel part of my question? should the filter drain at all after letting the bike sit for a day or two? could the fuel be leaking into the cylinder causing a hard cold start?

Hopefully you won't need to trim the spark plug wires, but if you ever need to cut them shorter you can splice wire onto the old wire using these:

www.ngksparkplugs.com/products/performan...plicers.asp?mode=nml

Regarding the fuel issue. If you believe fuel may be flooding the carbs and going into the cylinders when the bike sits idle for a couple days you may want to check the fuel level in the bowls using the clear tube method. You could hook up the tester, turn on the petcock until the fuel stabilizes at the correct level, turn off the petcock and then with the tester still attached let the bike sit or a day or so then check to see if the fuel level rises. Ed

Thanks. I'll give that a try.

So I got into town for work after 30 minutes of riding and I lose power. Pull over and the bike dies. Noticed the inline filter is not very full at all and the outlet is dry because of it. Going to remove the filter at lunch and hopefully that fixes that problem. I think the filter is too restrictive and can't keep up the fuel supply.