83 GS1100esd fuel problem?

[Fjbj40]

I am trying to get the ESD on the road. Engine rebuilt, everything adjusted as per manual. Carbs spotless, sonic cleaned, blown clear and reassembled with all new orings. factory airbox installed with filter.

This am I finally got to take it for a spin, but she is gutless! Fires up at the flick of the button, idles nicely at 1100rpm. But as soon as you hit about 4-5000 she stutters and feels/sounds like a twin! So I went back home effortlessly, got out infrared temp gun and sure enough #4 was not as hot as the others. I could sizzle spit on all except #4.

Ok I said, maybe I forgot a vacuum port, nope. Hmm, maybe a piece of **** got in the pilot jet, nope, even swapped it with #1, no joy. Ok, let's pull the carbs and try a set off a gsxr1100. Well she barks with those! So I take #4 off the rack, break it down and blow the **** out of every passage, but it all flows well. Passage from neddle jet to pilot circuit is clear, air jet for pilot circuit is clear as are all passages. So I adjust float heights to 20mm, reassemble, install and run, no better.

ok, relax, change the coil, no better.

I yank all 4 plugs, 1 and 4 are black while 2 and 3 are light grey.

so, can it be the Ignitor? But why did it run sooo good with the other carbs, maybe because there was no filters? I just slid them in the carb boots and fired her up.

I tried 4 new plugs, no different.

Should the air screws be at different settings for #1,4 vs #2,3?

thanks for any help!

[posplayr]

I would guess it is electrical because of the 1-4 grouping.
See you swapped out the coil
You could have a bad ignitor I guess.

Things to check:

Voltage to the coils. Same on Both coils?
How hot/blue is the secondary spark. Check for bad wires.

You could try and measure the average current through each coil to see if they match. If not suspect ignitor.
Double check the coil resistance should be 3-4 ohms.

Precautionary did you do a coil relay mod? You can also power the entire ignition using a relay.

[Fjbj40]

Yup, coil relay mod carried out along with main relay mod. Will do some ohm checks tomorrow. I looked at the manual and the only check for igniter is the meter check after disconnecting the igniter plug from signal generator to look for spark at the sparkplug.will give it a go.

[posplayr]

Yup, coil relay mod carried out along with main relay mod. Will do some ohm checks tomorrow. I looked at the manual and the only check for igniter is the meter check after disconnecting the igniter plug from signal generator to look for spark at the sparkplug.will give it a go.

I was suggesting measuring the coil currents under load. I suspect there is imbalance. The solution of course is to start replacing parts if imbalance is detected.

you have almost exhausted everything without finding anything so a careful analysis with measurements is warranted.

[bonanzadave]

a careful analysis with measurements is warranted.

Could he swap the coil input wires to see if the 1-4 issue moves to 2-3 ?

[Fjbj40]

Yes, that is the plan, sometime today. I sure hope it's a ignition problem. But I have another set of carbs going through the sonic cleaner tomorrow so I also has another set of bs34ss to use as troubleshooting.

[Fjbj40]

I pulled the carbs, again! Getting good at it now .

I now have my ignition problem sorted, bad ignition leads, or maybe just loose. I fooled around with it and it is running same temp on headers at idle.

However, at around 5000 she stutters, I am now thinking it is too rich on the MJ?

So, according to the FSM, I should have 112.5 main jet, it has a 122.5. Pilot jet should be a 45, I have a 47.5. Main air jet should be 1.2, I have a 1.6. The markings on the jets are CIB? Anybody ever heard of these?

When end I got the bike it had crap pods on it, I have since installed the factory airbox setup. I also have a set of 1150 cams installed, set to 105-107' IIRC, it's recorded somewhere.

So, I have done some research and from my readings it seems it is a good idea to go up a bit on the main and pilot jets to make the engine run better, in stock configuration, meaning stock airbox and maybe headers, which I have. But the readings say to go to a 115-120 MJ.

I have adjusted floats to 22mm, as per manual

I have a set set of Mikuni 115 MJ I am thinking of giving a go.

Advise please

[posplayr]

You seem to straddling the fence right now between pods and pipe and just pipes.

A stock 1100E with K&N pods and pipes should use a DJ3133 kit with the 132-138 DJ mains. Those are approx like 122.5-127.5 Mikuni jets. The big deal with that jet kit is to get the correct needles because you won't be able to eliminate a mid-range stumble without it. However, you got rid of the pods, which causes 3 times as much of a change as the 4:1 pipe on jetting.

What I would do one of two things:

A.) remove the lid from you air cleaner if you want to keep that 122.5 (asssuming it is a Mikuni equivalent) use the factory pro CV tuning guide to see if you can get it to pull to red line. You might need to go up another step to 125.0 because you changed the cams. If you cant get the midrange right go back to stock pilots.

B.) Put back in K&N pods (I have two sets I think virtually new), and go to the 130 mains. (I think I have both also). This is what hour bike is jetted for.

as s point of reference my 1100ed stock bore but 0.340 lift cams pods and Yoshi race pipe had your same setup but 140 mk mains. It was probably a little rich. Ran well.

recommend the NGK iridium plus , they will burn off a rich condition faster.

[Fjbj40]

I just found out everything is factory for the Canadian model, which this bike is. The only thing changed in the carbs is the main jet. So I am going to give the 115 jets a try and see what happens. They Re the only spare jets I have on hand so nothing to loose except my time.

Its odd that the Cdn model is jetted differently, however, up here in Canada we usually got the Euro spec'd machines.

I want to keep the factory airbox as this is going to become my long distance touring machine so I am after dependability and ease.

will see tomorrow how well the 115's work, just reinstalling them shortly.

Thanks for your help Pos

[posplayr]

I had Canadian carbs as well, main diff is they give adjustable needles.

i just realized I was running bs36 carbs instead of 34’s but as I recall jetting is pretty close between both.

on my stock 750 with k&n insert in air box, I stepped up to a 1100e intake valve and had to step up the main two points.

that was due to cam alone .

115 is very small!!!

[Fjbj40]

Well, carbs are back in with the 115 MJ, stock is 112.5 so it is up in size, although not by much.

Plug chops tomorrow if she pulls past 5000 or no stutter.

[Fjbj40]

The 115's were the fix! Pulls now, need to tweak the pilot screws as idle climbed to 1500 from 1000 and hesitates off idle a little once she warmes up.

This is a really nice riding bike! Handles great, but you can really feel the extra weight of a stock bike to my gs1085 road rocket, which tips the scales at 461 lbs vs this one at 540!

Cheers

[Fjbj40]

So, I am out 3.5 turns on the pilot screws, starts no problem, as she pretty much always did. However, she still rises to approx 1500 once hot, after 20 minutes of hard driving.

They are the stock pilot jets, all new OEM carb boots, factory air box. She also has an off idle hesitation when hot, but pulls hard once 3-3500 rpm has been reached. A feathering of throttle at hot idle is required to get off the line smoothly.

The hesitation is not there when the bike is cold.

Bike has 4:1 Wolf exhaust with a very quiet pipe for a 4:1!

47.5 is the pilot jet, maybe move up to a 50? I do not want to come out more than 3.5 turns on the screws as they seem loose right now.

What I found odd was very little change at hot idle from 2.5 to 3.5 turns.

[Fjbj40]

Here is the closure to the problem.

Even though my floats were set to the 22.4mm height, my fuel height was below the FSM specs! Made the tooling to check it in order to find this out. Once heights were set, no more rising idle once the engine gets hot that could not be tuned out with the pilot screws.

[GRAND ROUGE]

Here is the closure to the problem.

Even though my floats were set to the 22.4mm height, my fuel height was below the FSM specs! Made the tooling to check it in order to find this out. Once heights were set, no more rising idle once the engine gets hot that could not be tuned out with the pilot screws.

Good deal. What then is the current float level height? Or measurement of fuel level if using clear tubing at the float drain? Also...FSM....short for....? Thank you.