Hard to start,and only runs with choke on

So my 1982 Yamaha maxim 550xj is really hard to start.When I do get it started it only idols with choke open.Can turn choke of and keep a little throttle to it and it's good.Can someone please help?

 

how quickly do you turn off choke?
you should wait until rpms start to rise to around 1500 rpm. then gradualy turn choke down
idle rpm should be 1050 rpm set to 1100 rpm.

so give us a little history
did you ever check the valves.

hard start can be valves can also be vacuum leaks.


did you set mixture screws 2-1/2 turns from soft bottom

 

I haven't checked the valves sir,I just ordered new carberater boots cause mine were cracked,and I ordered a new fuel pedcock cause mine leaked.When running I leave choke on a little because if I don't it will die.Do I need to set all mixture screws at 2 and half turns?I cleaned carbs again today but waiting to put on when I get my other parts.Could it really be my valves needing shimmed?If so how do I know what size to get?

 

yes starting setting of mixture screws is 2-1/2 turns out from soft seat
you then have to sync the carbs make or buy a sync tool
if you do not hear the valves ticking away they need adjustment
it is easy to do just sounds hard just be careful when turning crank with wrench not to hit the pickup coils
do shims first then running sync
Bigfitz's AIRHEAD VALVE ADJUSTMENT with Pics - parts I & II

 

and what did you set idle speed at?

 

I just kept turning it,but wasn't sure the exact spot it should be

 

And thank u for all your help

 

Hmmmm there are 4 mixture screws, they are not on the throttle shaft the 3 there are sync screws. I am guessing that you are turning the knob out the back side of carbs that is the Idle knob.

mixture screws are located on top of carb throat engine side down a hole which may have had a plug in it

 

http://www.xj4ever.com/inside your carbs.pdf

mikuni carbs
in this link on page 20 you will see the mixture screw on page 11 you will see the tube it is located right side of photo vertical tube

for hatachi carbs go to this link
OWWW, My Eyes!

second photo mixture screw is in 6:00 position on each carb in a recessed hole
in the first photo you can see the brass colored knob used to set idle between carb 2 and 3 and in photo 5

confirm what you are turning

 

Sounds like you are not getting enough fuel at idle. Could be the pilot screw settings as xj550 mentioned. But it could also be an air leak on one or more of your intake boots, especially if they are cracked. You can check with a little propane around the boots. If the idle increases the you have found an air leak. Using propane I found that one of my intake gaskets was leaking. When I removed the boot about 1/4 of the gasket was missing.

 

Had similar issues and I definitely had a vacuum leak, take some starter fluid and spray it on the carbs to see if there are any other leaks besides the boots ( I had it on the valve shafts) and you may need to clean your carbs too if you haven't done that.