does fuel flow thru the idle jet at all throttle positions?

the_gr8t_waldo

Joined
Apr 7, 2007
Messages
624
Location
Tacoma, wa
I ask because two days ago I started up the motorcycle, after it sat for a number on months parked on the side stand. On starting it only ran (poorly) with the choke on ,and sputtered to a stop when I gave it any throttle. After some time I did get it to run and ran it around the neiborhood for about an half an hour, where it would konk out at all stops when I wasn't quick enough to take the throttle up well past it's idle position. It's apparent that the idlejet is blocked from fuel slowly going bad. After reading a lot of threads, here, I've decided that I'll try to run some kinda carb cleaner to clean out the idle jet to near normal state. After I replace the existing fuel and fuel filter, and adding the carb cleaning agent, I'll spend a day simply running up miles. And I have two choices... Either stop n go traffic, or freeways. Freeways will be easiest to do. Stop n go and I'm thinking that pulling the carbs and cleaning on the work bench, will be easyer.Is there one of the methods that increases the fuel flow thru that jet?
 
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Try it on the two-lanes or freeways first and see what happens. But first check the fuel shut-off valve by bypassing it.
 
To answer your thread question; yes, there is fuel drawn through the idle jets at all engine speeds. Utilize some "Sea Foam" fuel treatment at a fairly high concentration, along with fresh fuel, and run some highway miles. It may take a tank full or two to get the things cleaned up. And as stated above, check the fuel shut off.

If the bike is going to set for a long time, use Sea Foam before storing and, if possible, start it and let it run for a few minutes each week or two.
 
Fuel valve has been in bypass for a few years now. I hadden't plan on leaving that long without fuel treatment. But you all know how it goes. Life happens and pretty soon one month morphs into nine. Thank you sirepair that's what I was looking for. Just would like to avoid having to pull the carb set. Who knows, I might have to anyway Thank you both
 
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the_gr8t_waldo said:
Fuel valve has been in bypass for a few years now. I hadden't plan on leaving that long without fuel treatment. But you all know how it goes. Life happens and pretty soon one month morphs into nine. Thank you sirepair that's what I was looking for. Just would like to avoid having to pull the carb set. Who knows, I might have to anyway Thank you both
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Any luck? I'm in the same boat as you. I let Seafaom sit in it over night and cleaned out the fuel system to the carbs. Drained the seafoam this morning and primed the new filter (and lines forward of the filter) with 25% seafoam 75% fuel. Its finally firing again but no idle. It did idle fine on the choke before seafoam.
 
sirepair said:
To answer your thread question; yes, there is fuel drawn through the idle jets at all engine speeds. Utilize some "Sea Foam" fuel treatment at a fairly high concentration, along with fresh fuel, and run some highway miles. It may take a tank full or two to get the things cleaned up. And as stated above, check the fuel shut off.

If the bike is going to set for a long time, use Sea Foam before storing and, if possible, start it and let it run for a few minutes each week or two.
Click to expand...

I decided to give Sea Foam a try based on what I'd read here on this forum. Someone had pointed out that I had bought a 21 year old bike with only 29K which pretty much assured that it had spent a lot of time just sitting. I noticed an improvement as far as smoothness with the first tank and more with the second tank (per instructions on the bottle, I used approx 8 oz per tank so you get two tanks out of one bottle) . The first tank I pretty much burned through in two days. Then we got a bunch of rain and I didn't ride for about a week so the bike just sat, presumably with Sea Foam treated fuel in the float bowls. The next time I started it, it seemed a LOT smoother, like it was hitting on all four cylinders all the time. Very noticeable difference, so perhaps there is something to be said for just letting it sit for a while..
 
I just got back from a biz trip to SoCal, so I haven't addressed the mc problem. The plan is to swap out fuel and filter...then add cleaner, and run a bit. Then it'll sit for a few days. Later in the week, I'll have some time to run a few tanks thru the systems hoping that'll restore the good natured motorcycle to it's former state. Back on Tue. I had the bike running, but it wouldn't run with the choke off and throttle in the idle zone. At the time I was all suited up for the trip south. I didn't have the luxury of being able to research about this and was a bit chicken about setting out. Used the car and with the high temps, that turned out to be a good choice.. High temps on Sat. Were 118F
 
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If the idle jets are really clogged, the sea foam won't cure the problem. I just tossed two idle jets which wouldn't clear even with a brass wire. They can be stubborn. The 1100 is made to be ridden, not parked.

(BTW, I first pulled the carbs on STick back in about 96 after the VFR was getting most of my attention. I've done it several times since, both on my bikes and others. This is the first time I've not been able to clean them. :D )
 
I wonder if the smaller EPA idle jets add to the clogging problem.

And yes, a Happy ST1100 is one that gets ridden Often and Far.
 
the_gr8t_waldo said:
"The 1100 is made to be ridden, not parked"...then why the heck do they include two stands? ( one side and the other center)
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The side stand is for convenience and when "sack" is lacking to put it up on the center stand.:grin: The bike up on the center stand is proof that some of us feel more manly at the end of a ride than others and like to show off.(I'm pretty sure getting it up on the center stand first try every time is a true test of potency):superman::weights1:
 
ok, been trying to start the bike with new fuel filter and fresh fuel in place. and it just won't start...some firing of the sparkplugs but nothing that approaches a "start". so it looks like what I'll have to remove the carb set and clean the idle jets. I was hoping to avoid it, but if I want a running bike, I'll have to. thanks to all for the replies.
 
the_gr8t_waldo said:
ok, been trying to start the bike with new fuel filter and fresh fuel in place. and it just won't start...some firing of the sparkplugs but nothing that approaches a "start". so it looks like what I'll have to remove the carb set and clean the idle jets. I was hoping to avoid it, but if I want a running bike, I'll have to. thanks to all for the replies.
Click to expand...

You might check the fuel pump first. Easy as pulling the hose to the carbs off the metal tube coming from the top of the tank, replacing it temporarily with a longer one routed to a jar or bucket. Turn on the ignition and watch the fuel flow. You should get x amount in so many seconds. (Its in most of the manuals, none of which i have in front of me.) But basically youre just looking for a healthy flow.

FWIW, i just completed a carb rebuild on a 93 per the excellent tutotial elsewhere on this site. The bad news is, recommended parts alone totalled $400. Thats not including $70 for the special tool needed to remove the mixture screws. The good news: rebuild itself is pretty straightforward. Its not even that bad getting the carbs off or back on... once youve done it of course it will seem simple. Also great opportunity to replace coolant hoses, thermostat and other stuff thats under the carbs while u have them out. The reward - a smoooth running ST, was well worth the $$$ and downtime, at least to me.
 
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