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General Category => Maintenance => Topic started by: Dave-Tas on February 19, 2014, 01:41:18 AM

Title: Choke issues
Post by: Dave-Tas on February 19, 2014, 01:41:18 AM
When i start my bike i cant use choke, i have to warm it up with throttle untill it will idle  :sorry:

When i apply the choke bike will die and i can hear a sucking noise. if i apply choke and hold throttle on it just seems to fuel up.


FJ1100 84
pilots 40
main 115
4 into one
needle in 4th grove.
Title: Re: Choke issues
Post by: Pat Conlon on February 19, 2014, 02:51:43 AM
Are your carbs clean? This Sounds like a clogged choke circuit or the choke rod and/or linkage is not actuating properly. When the tank is off, and you rotate the choke collar at the handle bar, can you see the cable pull the rod and plungers on the carbs? Full range of motion?
If that checks out fine, then it's time to clean the carbs, then synchronize them.
Title: Re: Choke issues
Post by: Dave-Tas on February 19, 2014, 03:51:50 AM
Cleaned carbs (maybe incorectly) and synced a few days ago  :dash1:
Title: Re: Choke issues
Post by: Pat Conlon on February 19, 2014, 11:58:31 AM
Carb cleaning 101: Half measures will avail us nothing.
Title: Re: Choke issues
Post by: mr blackstock on February 19, 2014, 11:33:20 PM
G'day,

the choke cable and actuating mechanism on the carb bank was very hard to use on my '85.  I had to change how it was mounted and everything just to get it working well.

That could be similar to your issue?

cheers, Gareth
Title: Re: Choke issues
Post by: Dave-Tas on February 20, 2014, 02:17:48 AM
The mechanism is workin ok the problem is that it just pulls in too much fuel.

The vent hoses are clear as i can blow through them. any attempt to use the enricher just richens it to a stop.

Any other options/ideas.

Title: Re: Choke issues
Post by: andyb on February 20, 2014, 08:11:22 AM
You sure that it's going too fat instead of an instant air leak, killing your vacuum?  Because that's more what it sounds like.
Title: Re: Choke issues
Post by: FJmonkey on February 20, 2014, 09:39:46 AM
With your jetting changes you may not need full choke. After my Suppertrap slip-ons, UNI pods and re-jetting I find full choke is too much in the always nice Kalifornia climate. Have you tried different choke positions?
Title: Re: Choke issues
Post by: FJ_Hooligan on February 20, 2014, 01:04:25 PM
Plugged choke fuel jet in the float bowl
Title: Re: Choke issues
Post by: Dave-Tas on February 20, 2014, 02:54:10 PM
Quote from: andyb on February 20, 2014, 08:11:22 AM
You sure that it's going too fat instead of an instant air leak, killing your vacuum?  Because that's more what it sounds like.


Not sure of anything  :dash2:, does smell rich and fuely. Its like pulling the choke on a warm bike, where could the air leak be in the choke circuit, bike runs sweet and will warm up with just a little throttle.just cant apply choke so it will warm up while i get ready.


Quote from: FJmonkey on February 20, 2014, 09:39:46 AM
With your jetting changes you may not need full choke. After my Suppertrap slip-ons, UNI pods and re-jetting I find full choke is too much in the always nice Kalifornia climate. Have you tried different choke positions?

yep  :good2:



Quote from: FJ_Hooligan on February 20, 2014, 01:04:25 PM
Plugged choke fuel jet in the float bowl

Didnt find any blocked jets but will find some pics and make sure i am looking at the right jets. :wacko3:
Title: Re: Choke issues
Post by: andyb on February 20, 2014, 03:07:09 PM
If it dies as soon as you apply any choke at all (first click or whatever), something is WRONG.  If the fueling is way rich, it should blubber a bit but you should be able to keep it running if you open the choke at a fairly high rpm (say 4k or so on the throttle held steady, open choke... it should keep firing, though sounding cranky about it).

I'd say pull the plugs and find out, but if it's immediately dying, you won't really learn much, not enough time to develop the necessary color.

It's also possible that you left out some necessary bit someplace or put the fribitz in backwards or whatever etc, when you cleaned things.


If it's working for you the way you're doing it, and it's starting consistently, then fuggit.  Get a friction style throttle lock, and use that as a temporary idle-turner-upper until it's able to hold a normal, steady idle.  Would drive me nuts to not know what the issue was though.  If it's ridable from cold without the choke, did you happen to recently put pods on it?  And perhaps get some with an assload of oil?  That's the only way that I can think of to cause a significant enough restriction to be so rich to not need it and have too much when you use it (assuming the carbs are fine internally).  

If you've just rejetted from stock as well, you will definitely need less choke than you did for a comparable weather situation.  Those bigger pilots make such a lovely difference.

There's only so much to the choke circuit.  Bad seal at the plunger where it enters the body?  Bad oring on the end of the thing?  Broken off pin on the end of the plunger thing?  No clue.  Would have to go in and fart about with it.  The 'sucking noise' worries me a bit, because that sounds like something from an air leak (vacuum loss) instead of the sound of fuel cavitating or something as it blows through the circuits.  You'd need a silly amount of fuel to be audible over the motor's racket and the exhaust, like firehose silly amounts, I'd think?

Easiest answer is of course to just send the carb rack to Randy, though he'd be a bastard and get it spotlessly clean, then you'd have to spend until the end of time cleaning the rest of the bike to match.
Title: Re: Choke issues
Post by: FJ_Hooligan on February 20, 2014, 04:20:52 PM
From the Carb files (good shit worth reading):


Choke Circuit Tips for the FJ
During a carb rebuild or cleaning, check the condition of the choke plunger tips.
The rubber must be in good shape for the plungers to seal properly. Also check
the tips of the plungers where the clips from the choke rod pulls the plungers. On
older FJs, vibration of the clips can "eat" into the tip of the plungers causing them
to snap off. Periodically oil the choke cable, the plunger shafts, and the choke
rod where it slides through the carb body to keep the choke working smoothly.
Also, the choke circuit pulls fuel from the float bowls through a small passage on
the side of the float bowl. If you look at the bottom of the float bowl, you will see
a small hole that supplies fuel to this passage. There is an orifice in that hole
that can easily get blocked by debris or old dried out fuel "varnish." If this
happens, the choke circuit will not get any fuel making the FJ very hard to start
and cold natured beast until it warms up. When you clean the float bowl, make
sure this orifice is not clogged up.
The best way to do this is to shine a flashlight
into the hole at the bottom of the float bowl and look down the tube on the side of
the float bowl. If you see light in the tube, the orifice is clear. If you don't see any
light, spray some more carb cleaner into the hole until it shoots out the tube.
Title: Re: Choke issues
Post by: jscgdunn on February 20, 2014, 04:44:28 PM
Quick question: is the air box installed?
Title: Re: Choke issues
Post by: Dave-Tas on February 20, 2014, 11:40:23 PM

Quote from: andyb on February 20, 2014, 03:07:09 PM
but you should be able to keep it running if you open the choke at a fairly high rpm (say 4k or so on the throttle held steady, open choke... it should keep firing, though sounding cranky about it).

It's also possible that you left out some necessary bit someplace or put the fribitz in backwards or whatever etc, when you cleaned things.

If it's working for you the way you're doing it, and it's starting consistently, then fuggit.  Get a friction style throttle lock, and use that as a temporary idle-turner-upper until it's able to hold a normal, steady idle.

There's only so much to the choke circuit.  Bad seal at the plunger where it enters the body?  Bad oring on the end of the thing?  Broken off pin on the end of the plunger thing?  No clue.  Would have to go in and fart about with it.  The 'sucking noise' worries me a bit, because that sounds like something from an air leak (vacuum loss) instead of the sound of fuel cavitating or something as it blows through the circuits.  You'd need a silly amount of fuel to be audible over the motor's racket and the exhaust, like firehose silly amounts, I'd think?



Does run choke on high revs.
Had problem when i brought it just before xmass.
fuggit Throttle lock has been thought about.
Must disassemble again after poker run this weekend  :good2:


Quote from: FJ_Hooligan on February 20, 2014, 04:20:52 PM
From the Carb files (good shit worth reading):


Yep done that.  :wacko1:




Quote from: jscgdunn on February 20, 2014, 04:44:28 PM
Quick question: is the air box installed?

No, running pod filters
Title: Re: Choke issues
Post by: mikedastonfj1100 on March 30, 2014, 11:02:04 PM
Try doing another clean taking out every screw, needle, valve, and jet u can find.. Then reassemble to see what happens... Could be cable issue also... I Have had the same problem with a 1990 Suzuki dr 350 dirt bike... I did a full clean with all parts removed then put back in... Worked fine after...