Too small an airjet

[Rein]

So I stumbled on something strange. I have 150 small air jets on my carbs for the 650gl, but all the other jets are correct. 150 air jets are for the 550. Ever since I got the bike, it's been pretty much unrideable. It hangs after it warms up, stumbles from a moderately quick turn from idle. From what I've been told by chef, too small an air jet means not enough air fuel mixture over all, am I correct? So no matter the jetting or adjustment, there just isn't enough fuel mix coming through, right? Is my theory sound?

650gl, no mods, new carb boots and intake orings, perfectly pliable air box boots, no leaks in the airbox, new battery, stator, Honda r/r, valves adjusted and synced.

[JTsGS650]

I found the same thing in my 650 during my carb rebuild. 150 air jets when the Factory Service Manual indicates that they are supposed to be 160s. I'm not sure if it's a misprint in the FSM or if someone at the factory screwed up when installing air jets.

It's possible that it may run a tad rich if they are actually supposed to be 160s but wouldn't make the bike unrideable. Soundd like you may be running lean if your idle is hanging. Does it smell rich? What do your plugs look like?

[Rein]

I found the same thing in my 650 during my carb rebuild. 150 air jets when the Factory Service Manual indicates that they are supposed to be 160s. I'm not sure if it's a misprint in the FSM or if someone at the factory screwed up when installing air jets.

It's possible that it may run a tad rich if they are actually supposed to be 160s but wouldn't make the bike unrideable. Soundd like you may be running lean if your idle is hanging. Does it smell rich? What do your plugs look like?

Doesn't smell rich... but damn, I hoped that would be my problem... Actually, all my plugs are black, but haven't taken it out to ride, ever. Just sat in the garage while I wrenched away at it. Also, I can't hold it at a steady rpm either. she'll idle at 1100 or whatever rpm i set the throttle screw at, but if i try to hold her at, say 2000 or 2500, she'll hold for a few seconds then zoom up like an intake leak.

I may just do another cleaning and install another set of jets and needle jets, tighten everything down nice and firm.

[tkent02]

Why not just ride it?

[JTsGS650]

Have you completely disassembeled your carbs and dipped them over night and replace orings with robert barrs kit? Check that your enriching circuts are all closing?

[Steve]

Like all other circuits in the carburettor, fuel flow depends on air flow to move it along. If your (pilot) air jets are too small, there won't be enough air flow to draw the right amount of fuel through the (pilot) fuel jets. Although it might tend to richen the mixture just a bit, you won't get nearly enough of it to matter.

.

[chef1366]

I'm wondering if he has 550 carbs on a 650.
I'm supplying him with
160 pilot air jets
Main jets
Spacers for the needles
Needles for the 650
Needle jets
Idle mixture screws
Rubber plugs if he needs them
He says he has four 42.5 pilot jets.
He thinks he may have damaged the jets cleaning them.
I told him to check compression and run the bike on prime with the vacuum line on #2 blocked. He states the #2 isn't heating up.
I hope the float needle valve/seat and float are good. I have all these items if needed also. I may just throw a set in.
I hope he's running the rubber plugs under the pilot jets.

[Rein]

Why not just ride it?

I attempted a few times in the last week. It never returns to idle correctly when I'm riding. IE, Get up to 4500 in first, pull in the clutch, and she hangs at 4000. Sometimes she drops to regular idle, sometimes she hangs. Being my first bike, it's a scary situation for me to feel like I'm out of control when I'm on it. Just want it running smoother before I do anything.

Chef, I got new plugs a few months ago, along with new gaskets, and new float and float seats from z1.