84 GL1200 carburetor jets

[Ivas2311]

Howdy all, I'm in central texas and daily ride my gl1200. Her speedometer is either rolled over or it really only has 2000 miles (unlikely I know.) Anyway. It runs great. It's the ultimate commenter for me. I was recently looking for piston rings as I'm reading about 120-130 psi across the board. Unfortunately parts are all discontinued. My issue is with my needle jets. The bike runs a little rich. I can see it on the plugs. When the throttle is closed, like coming to a stop, my RPMs dip down. I think my needle jet/needle jet seats are worn out. I was trying to find just needles and see if that does anything, but again, parts are scarce. I know 32mm cv carbs were used on many bikes from the 80s. If anyone has any recommendations, websites, shops, or users that might have what I'm looking for please let me know. I'm just trying to do my part by keeping one more wing on the road.

Thanks and gig'em,
Isaac Vasconcellos

[Bike...and Dennis]

Hi. I'm not sure how you determined it's a needle jet problem but they don't really wear out. Unless that's really 602,000 miles.
As far as the compression goes, how did you do it? Should be done on a warm motor with the throttle wide open. Again, rings easily last several hundred thousand miles on these slow spin Honda motors.
Where are you located?

[Ivas2311]

College Station Texas. I suspect it's the needle jet because when coming to s astop and the throttle is fully shut and the clutch is pulled in the rpms drop down to about 600-800 then come back up to 1200. When I'm downshifting or close the throttle and engine break I get a few pops. I am sure my anti afterburn valve is working. I have disconnected it and rode around and I can clearly tell the difference. I'm running stock jets as far as I know.

[joecoolsuncle]

needle jet and jet needle is the long tapered needle that hangs fron the slide, and its orifice it drops into, you are referring to the float valve.
cant get true compression 9COLD CRANKING PRESSURE), unless throttle is opened fully AND slides are fully open.

[Ivas2311]

I have done compression tests exactly like that.. This isn't my first rodeo. And no, I am not referring to my float valve. A have adjusted my floats correctly and have no issues with my float valves leaking. My primary concern in my needle valve. Does the needle valve (yes the one in the slide) not have control over idle/lower rps? I have thought about adjusting my floats to cut off a little sooner to lean out my mixture but was hoping someone on here could point me in the right direction. I have been a member on this forum for over a year and I've done a lot of reading.

[joecoolsuncle]

was confused by you saying needle jet seats. sorry. i have seen needles wear. they wear on one side usually, and on the tapered part.usually on off road bikes and atv. a blubber at around the 1/8 to 1/4 mark on throttle usually gives reason to inspect. once parts pulled, you will see a gray streak on side of needle.
have you considere your slides may be sticking/ fluttering?

[Ivas2311]

It has crossed my mind multiple times. I run a little bit of magic mystery oil in my tank to keep my slides functioning well. I seriously doubt it's the slides. I think the underlying issue is I'm running rich. I know these bikes had a recall in the late 80s for a slow speed stumble off idle. My bike really does run like a rape date. My fuel economy is less the good though. I figured I was just dumping a little too much fuel. I'll average about 35 +-3 mpg. My main concern is longevity. If parts aren't available now, they definitely won't be available in a few years if I have to do a full refresh. And God knows I love the thing too much to sell it.

[84wing1200a]

So with CV carbs and the bike attached to them, they function solely on the calibrated intake and degassing of the incoming and outgoing intake of fuel and air coming in. In simpler terms, a rust hole in your exhaust can slightly throw off the balance of the air to fuel ratio. This can be negated by increasing the idle (~'85 honda service bulletin/slow jet increase) jet and/or the main jet. My recommendation is getting a jet kit and service your carbs, take painstaking care to polish everything as you go. This will help circumvent the popcorning (back pop through exhaust) that you notice during hard deceleration.

However, without pulling out strong mechanical diagnostics, you really are at the mercy of trying to be proactive with the jetting. Its sounds weird to replace smaller with larger and increase the MPG, but with a increase in this area with a proven carb balancing, you will find monumental gains in both seat of your pants and your gas station fill up.

Also, I am new to wings, but raised around fathers. I have noticed that the SAS on these bikes are a failed emission design. I would recommend removing that all together if the above doesnt correct your issues. As this is a big air source for lean conditions in deceleration aspect, especially factoring the afterburn condition.

Also I am in Ft Worth. Nice to see some Texans in the house.

[julimike54]

Had the bike been setting for a long while before you took ownership?

[Ivas2311]

Yes. I'm unsure how many years, but it was a literal rats nest. It was used as a parts bike.

[joecoolsuncle]

So with CV carbs and the bike attached to them, they function solely on the calibrated intake and degassing of the incoming and outgoing intake of fuel and air coming in. In simpler terms, a rust hole in your exhaust can slightly throw off the balance of the air to fuel ratio. This can be negated by increasing the idle (~'85 honda service bulletin/slow jet increase) jet and/or the main jet. My recommendation is getting a jet kit and service your carbs, take painstaking care to polish everything as you go. This will help circumvent the popcorning (back pop through exhaust) that you notice during hard deceleration.

However, without pulling out strong mechanical diagnostics, you really are at the mercy of trying to be proactive with the jetting. Its sounds weird to replace smaller with larger and increase the MPG, but with a increase in this area with a proven carb balancing, you will find monumental gains in both seat of your pants and your gas station fill up.

Also, I am new to wings, but raised around fathers. I have noticed that the SAS on these bikes are a failed emission design. I would recommend removing that all together if the above doesnt correct your issues. As this is a big air source for lean conditions in deceleration aspect, especially factoring the afterburn condition.

Also I am in Ft Worth. Nice to see some Texans in the house.

im sure he understood that. cant teach carb jetting on a forum, but you can help the fellow out by telling him how to diagnose. its the basics dude. if he had strong diagnostic skills and understood proactice jetting {whatever the hell that is} he wouldnt be here. tell us precher boy? what ignites unburnt fuel in the exhaust? we are here to help others, not promote ourselves. its like www.imanidiotwithashed.com custom bike builder. shees there is plenty of those already.

[Ivas2311]

What exactly are you referring to with unburnt fuel in the exhaust. I'd suspect way to rich or fault timing/value trian.

[joecoolsuncle]

What exactly are you referring to with unburnt fuel in the exhaust. I'd suspect way to rich or fault timing/value trian.

simply too much fuel does not get burned in the combustion process and passes through the exhaust. it collides with fresh, cooler air somewhere on the way out.
too much fuel through the intke caused by
too little air into intake
normal fuel air, but lack of spark
lack of compression
slow timing
too high an octane
cold temps at chamber
reversion
yada yada

[Ivas2311]

Yeah I don't think those are any of my issues. I've gone through my ignition system, replaced belts and pullies and double checked my timing. Checked for vacuum leaks. Next time try to be a little more helpful rather than just putting people down.

[84wing1200a]

[/quote]
im sure he understood that. cant teach carb jetting on a forum, but you can help the fellow out by telling him how to diagnose. its the basics dude. if he had strong diagnostic skills and understood proactice jetting {whatever the hell that is} he wouldnt be here. tell us precher boy? what ignites unburnt fuel in the exhaust? we are here to help others, not promote ourselves. its like www.imanidiotwithashed.com custom bike builder. shees there is plenty of those already.
[/quote]

Well my apologies for the offense you have taken, my post was not intended to elicit such a response. I was helping to explain the nuance of how picky a CV carb setup is. If you felt my post was afront, then by all means go pound sand and puff ya chest. Moving on, unburnt fuel in the exhaust is ignited by the temperature within exhaust and the correlate backpressure present.

Ivan, if you would like you can purchase a jet size higher, install and see if this corrects your issue. I understand you have done tremendous amount of maintenance level work and have replaced a ton, my opinion and help is just that to help think outside the box and try something most people have not done.

[Ivas2311]

The fact that you suggested that I try bigger jets leads me to believe you haven't even read the original post and that you're here to sir up trouble.

[julimike54]

Yes. I'm unsure how many years, but it was a literal rats nest. It was used as a parts bike.

The low compression numbers are probably due to the lack of use. Several have had this condition and every time the recommendation is to ride it for a few hundred miles and then recheck. I only remember a couple of cases where the compression didn't come back. Even though it's not running well, try to run it for a while and see if this improves the compression numbers.

I didn't see what you're using for your reference material, Honda or Clymer or ? The carbs are quite finicky about the procedures used to "set" them.

I like this procedure for reviving old bikes...just FYI
https://www.randakksblog.com/starting-a ... /#more-687

The Marvel (MMO) used at what dosage? I used to use about an ounce or two per tank, now I use cheap ATF at 1 oz. per gallon, it seems to work better than the MMO. I've had lots of carb issues in the past and since changing (knock on wood) nothing has gone wrong. Just a suggestion to try, but it won't change on the fist tank of fuel, probably notice it around the second tank. I think it works as a cleaner and lubricant.

Best of luck, seems it's needed for these old rides.

[joecoolsuncle]

you wont get accurate compression CCP numbers on cv carbs unless you pull the slides or prop em up. holding throttle wide open for compression test doesnt move the pistons like you need. i wouldnt sweat a low number, as juliemike said.

[84wing1200a]

The fact that you suggested that I try bigger jets leads me to believe you haven't even read the original post and that you're here to sir up trouble.

Ivas, was only trying to help. But I’ll shut up and color.