FJ1100 Needle Jet Assembly Order

[Miker]

You have capped off the correct ports on the carbs.  Those go directly into the intake and must be capped off, so you're good there.

The Dyna ignition also works as wasted spark.  This is a product of a 2-coil shared ignition layout. 

How does the exhaust smell at idle?  With the large idle jets it should smell very rich.

Thanks David. It doesn't smell overly rich. No black smoke either. The mixture screws are 1.25 turns out though. I'm going to swap out those jets when I get the chance.

[racerrad8]

What is the overall length of the main jet needle?
What is the overall length of the emulsion tube?
Is the emulsion tube shrouded or not?
What do you slide springs look like?
Have the slides been drilled out?

Are all of the slide curved bottom?

I also took the high vacuum petcock failure rate out of the equation by installing a 10mm inline shut off valve in the fuel line while maintaining proper length and routing. I just leave the petcock on prime.  The original fuel filter is in the petcock and in good shape. I don't know how to check the valve at the gas cap.

This confuses me...

Did you leave the stock petcock hooked up to the vacuum line or removed the line and capped at the intake?

Randy - RPM

[Miker]

The main jet needles are 57mm long
The emulsion tubes are a tad over 40mm
The tubes I'm using are not shrouded ; they are from Japanese rebuild kits. I attached a photo of the OEM next to the aftermarket tube and a pic of my old OEM tubes. I don't think I see ovals, so I can throw them back in if you think that would help.
The springs look OK to me and seem to work properly. The slides have a smooth open and close action; not too fast or slow. 
I doubt the slides have been drilled out as the carbs contained all stock components when I got it.
Yes all the slides are curved.

I left the stock petcock and capped the vacuum port at the intake.

I installed the only reasonably sized jets that I have on hand, which are 42.5 pilots and 122.5 mains. Mixture screws three turns out. I attached pics of a couple plugs from a long aggressive 6-7k rpm ride and a long easy going 4k rpm ride. The insulators still look too white to me, but there's no backfiring, performance seems ok, and so far gas mileage seems a lot better, though I won't know mpg until the tank is done.

Thanks very much
Mike

[RPM - Robert]

The unshrouded emulsion tubes are for the early 1100s and use a flat bottom slide and a shorter 52.50mm length needle.

The shrouded emulsion tube used with the curved bottom slide is made for a 57mm main jet needle which is what you have currently.

So you either need to get new emulsion tubes that are shrouded or put the other ones back in to start with. If you don't know exactly what you're looking for it is very difficult to tell if they are worn or not. Either you have a 1100 that was built later in the year or someone changed the components at some point.

42.5 pilot would be fine with a 160 air bleed. If you have 155 air bleeds you need to go to a 40 or bump the air bleeds to a 160

122.5 is still too rich. You should probably be around a 112.5 or 115 with a stock motor and air filter with no other mods.

Take a picture of the slide springs and the hole in the slide.

[Miker]

Thanks Robert.  I attached those pics.  Looks like the slide holes are 5mm and the springs are 115mm.  I have a Supertrapp 4in1 full exhaust and individual pod filters. 

[RPM - Robert]

The springs are stock but if the holes are 5mm they have been drilled. They are only 4mm from the factory.

[Miker]

The springs are stock but if the holes are 5mm they have been drilled. They are only 4mm from the factory.

Sorry I read the calipers wrong. The holes are 4mm

[Miker]

122.5 is still too rich. You should probably be around a 112.5 or 115 with a stock motor and air filter with no other mods.

I have individual pod filters, crankcase filter, and a 4 into 1 supertrapp exhaust. What size main jets would you recommend for that setup?

[Miker]

Should have added this comment a while ago.  I found a carb calculator that I used to jet my bike: https://raggedmoto.com/carburetor-jet-size-calculator/

[Pat Conlon]

So...what did you use and how does it run?

[Miker]

So...what did you use and how does it run?

42.5 & 117.5. Runs great!

[Pat Conlon]