Got my carbs open - Did the PO re-jet?

[wirelessguy]

Hi guys.

I have the shop manual for my 1100EZ but I can't really make heads or tails of it.

Air screws say 160 on them also some sort of icon (square within a square, not sure if that's a manufacturer thing). I'm referring to the screw on the intake side at roughly 8 O'clock. Does that sound modified or stock?

I looked at the service manual but I'm not sure which number I should be looking at. It looks like it say 1.2 mm? The manual says pilot Air Jet #170 but that would have been inside the carb not the outer air jet?

I popped the float bowl off for a sec just to get a photo of the main jet. That guy says R 125 I think. Same icon. Photo here...


I removed that pilot jet plug but peering inside it didn't look like it had any marking on it.

So did the PO rejet when he installed a V&H street pipe on my bike? It was rusted out so I replaced it with a V&H sidewinder header & pipe.. So I'm trying to figure out if my jetting is fine and I just go about a carb cleaning or if I need to order anything. One last comment, I still have the original front airbox but the rear was removed leaving just a clamped on air filter. (not sure if that was done for more air flow or if he had issues getting to the battery).

I already have my O-rings in, just trying to figure out if I dip my jets in Berryman's or get new ones.

Thanks.

[cowboyup3371]

The pilot jet's marking are extremely tiny and you won't see it while it's in its passageway. You will need to take it out and most likely need to use a magnifying glass to see anything (I could barely read mine).

[Big T]

The little boxes are the Mikuni symbols, so you have genuine Mikuni jets in there

You should be removing the jets,diaphragms and dipping the carb bodies and jets in Berrymans per the carb cleanup

[wirelessguy]

Good news, so I've got Mikuni jets and not the Dyna ones.

I did some searching here and it looks like the stock main jet for the Z is a #110 and folks have written that the V&H sugg spec is for a #125. (I just have to hope that this is consistent between the V&H street and sidewinder) I've yet to check the pilot jet but if I'm right that would likely have been modified from the stock #45 to a #47.5
No telling what the complete rear airbox removal was all about but I'll just have to wait and see what testing is like once I clean and reassemble everything.

Thanks.

[Steve]

My information says that stock jets would have been:
112.5 main jet
160 pilot air jet (the one in the intake throat, and they are not "screws")
47.5 pilot fuel jet (the one under the rubber plug that you have not removed yet)

If you have 125 mains, then yes, it has been re-jetted up 5 sizes.
If you have a stock airbox, that might be a bit rich. If you have pods, it would be on the lean side of just right.

Get some new screwdrivers that just barely fit the slots in the jets, remove them all. Remove the float valve and the idle mixture screw (the one on the top of the outlet of the carb, might still be under a sealed plug). Then get some "dip" and clean those things. While you are waiting for the carbs in the dip (each one for a full day), order some new o-rings from cycleorings.com.

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[wirelessguy]

Already got the O-rings here. :-)

I plan on getting to the dip shortly but my space isn't heated - plus I need to clear off some space so that little parts don't go popping all over when I do the disassembly. I'm more worried about that than anything else.

[Steve]

Does not take much room, but get some foil muffin tins to hold the parts and have some good light.



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[wirelessguy]

Question... one of my concerns are getting the choke springs off and back on again (seems like a lot of tension there). I'll have to give it a good look or even take a simple video while removing.

Is it safe to put all those metal parts into the dip or should I shy away from springs and components that normally go on the outer housing? If so, I'll likely get some other sort of degreaser.

[Steve]

The "choke" springs are very light. It's possible that you have identified something incorrectly.

The "choke" mechanism is that little tip that sticks out the upper left corner of the outlet (engine side) of the carb. Remove the large nut around it with a 14 mm wrench, slide out the nut (retainer), the spring and the plunger.

What were you calling the "choke spring"?

The larger, threaded hole at the top of the carb body is where the "choke" lives.
(This carb is completely stripped, and is either ready to go in the dip or has just come out.)


.

[wirelessguy]

You're right, I stand corrected. The choke spring is on the horizontal rod. What I was referring to were the throttle springs which are hefty and attached to the holder that lifts vertically at the center of the carbs.

In either case, is it safe to dunk any of those springs?

[Steve]

Yes, the entire throttle assembly can be left attached.

Some have expressed concern that the plastic bushings on which the throttle shaft pivot would be eaten away by the "dip", but I have not seen that happen, even on one carb that was accidentally left in there for four days.

.

[wirelessguy]

OK, finally disassembled the entire carb and here is what I've got. I'm not sure what to make of it all. Carb #1 readings...

Air Jet - #160
Main Jet R 125
Needle Jet 338 (symbol) x-1
Pilot Jet (symbol) 30
Unless I'm reading it upside down (kinda small - read with screw thread toward top).

I was under the impression that the pilot jet should have gone from 45 to 47.5 but I guess I'm wrong. a #30 would seem way off though.

Any ideas?

Thanks.

[chef1366]

All the pilot jets say 30? I hope not
If so it probably wouldn't idle without choke. Look again

[wirelessguy]

Yep. Just opened the second carb. Also says 30 on it.
I think I wrote some of this above but (a) the bike has the entire rear airbox missing (presumably to add more air flow) and (b) the bike would run while choked and allow me to idle at 1,500-2000 rpm but die as soon as I put her in 1st gear if she wasn't on the stand (i.e. any pressure on rear wheel at all).

Do you think I should just buy a set of 47.5's and see what happens? Any sugg vendor out there? I've seen some different types of pilot jets mikuni makes and want to ensure I order the right thing the first time around.

Thanks.

[chef1366]

Yes put in the 47.5s.
Someone switched them out before selling the bike or something. There is no way it ran with those in there. Maybe at wide open throttle only.