motorcycle carb issues

[bigretic]

89 Yamaha fzr 600
though I had it straightened out when I rebuild the carbs last summer. pulled it out of storage, hard start. runs smooth on hi/med. choke. low choke is rough, will not idle.
number 3 carb has no response at high choke when spraying cleaner in it. (all other carbs will raise rpm when doing this) in fact, if it's on a low choke spraying cleaner it the #3 carb will kill the bike.
took it apart, all 3 jets are clear so what gives?
I will double check tomorrow that #3 cyl is firing but i'm sure it is under choke.

 

[churchmouse]

There are pilot jets or part throttle jets in the carbs besides the maim jets. These are the ones you need to address.
As to the #3 issues is the bike running an all cylinders. All exhaust pipes hot.

 

[bigretic]

Yes, primary, secondary and idle. all 3 are clear.
I'm going to double check the spark.

 

[Bybo]

Check your carb boots for leaks. If they suck any air, that will make it run like ****

 

[sht4brnz]

...

 

[sht4brnz]

Did you separate the carbs from each other? If yes, you have a potential sync issue.
Did you remove the idle mixture screw? Did you notice the spring, washer, and O-ring? Easy to lose items if you didn't know they were there

 

[SmileDocHill]

I had a sportster with carb issues, over the course of 3 years it became a fat boy.

 

[bigbaloo95]

I had a sportster with carb issues, over the course of 3 years it became a fat boy.

I see what you did there.

 

[bigbaloo95]

Is this fresh gas? Had the same deal with my bass boat and found regular pump gas degrades extremely fast (as in weeks). That #3 carb is the kicker air leak would make the rpm rise.may just be the idle or the air screw extremely out of whack.

 

[bigretic]

Yes, the carbs were apart. Completely apart... There were missing parts when I took them apart. A few jets were not in as I recall. I got 8 carbs when I bought this bike... They are together complete and correct.
It is firing on all cylinders.
Mix screws were set to factory spec per the Yamaha service manual.
I do not think it is an air leak at the boots or anywhere else because of the reaction to fuel going in the carb and it stalling. If anything I would say it needs to be leaned out.
Also last night I covered each carb with my hand they are all sucking. They will begin to stall and readily recover when you take your hand off, except #3. Very slow to recover. So again I am thinking too much fuel not enough air on that carb.
What say ye?
I will mess with the mix screw and see what results I get.

 

[Bybo]

You can spray starting fluid across the boots to check for leaks. Get it idling and spray. If the rpms change, you have a leak.

 

[churchmouse]

Is the compression good across all cylinders.

Fresh plugs/gas

 

[bigretic]

Plugs and gas are good. compression test will be a bear. plugs were bad enough. Boots are not leaking. I messed with it most of the morning. I'm selling the bike as is, and i'm tired of messing with it.