Now Hands-On Help Needed Carb cleaning in Tampa Fla.

[Jeffintampa]

Thank you all for your help with my little projects I do on my 11. I think I have the carbs synced pretty close as the bike runs great! I am having a problem after it sets in the sun at work, I am pretty sure it has something to do with my floats and plan on a good cleaning this weekend.

My question is.
It I clean my carbs pulling most of the needles etc. when I put it back together will that mess up my sync?

[motoman]

Yup......carb bank removal alone WILL throw sync off.

[Rasputin]

+1 on what Motoman said! I also wonder how you will give them a good cleaning by only removing some of the needles. The triple clean idea came up simply because everyone would try to shortcut a clean and have to go back in. Far better to do it right the first time and be done with it.

[bikerphil]

I am having a problem after it sets in the sun

This seems to be a common problem with many XS11's that are running the factory airbox. Hold the throttle WO to clear it out.

[Bonz]

I am gonna disagree that removing carbs in and of itself changes the sync an appreciable amount. Had carbs on and off for many things and many times , and the mercury sticks show no major change. Unless you take the carb banks apart, mess with the sync screws, or the carbs are mechanically not sound, they are mechanically linked and those adjustments will not change themselves.

CZ and I sync'd a set of carbs on another bike of mine while I was doing a carb swap and jetting development, and 40+ times on and off the bike, changing jets, float height, needle shims, et al, the sync was so close the second time at the end as to be called spot-on.

If parts of individual carbs are dirty and clogged, and were sync'd that way, sure a sync is in order once they are clean.

I know I'm gonna probably catch some grief, but it is a true story and the same held true for my XS last summer when I took the carbs off to replace needle seat o-rings before the Colorado Rally.

[Bonz]

Oh, almost forgot while up on my sync soap box... Bike sitting in the sun? Tank gets hot? Has the gas cap vent been looked at?

Carbs don't get enough direct sunlight to make an appreciable difference, IMO.

Heat soak after running on a hot day, carbs or fuel yes. Sitting in the sun all day, check the tank vent.

[motoman]

This seems to be a common problem with many XS11's that are running the factory airbox. Hold the throttle WO to clear it out.

My Venturer acted that way from new, if hot from running and shut off for approx. 30min. or less. More than normal cranking of starter and a gradual roll-on of the throttle to start.
Forward several decades and way longer than should of been, dealing with voltage issues and fueling issues, accidently found screwing with bowl fuel levels (having carb bank off more times than I can remember) that being a bit on the low side bike fired with one tick-over after being ridden then shut down when hot. For correct fueling when ridden and easy re-start when hot, there IS a 'happy' fuel bowl level setting. Just getting there takes LOTS of carb re-moval/install, a whole lot more patience............and another 'turn-key' bike for when frustration level leaves it parked off in the corner of the man-cave.
BTW, the float needle tiny springs not all compressing the same rate doesn't help matters either.

[Jeffintampa]

My bike

Its really strange, just started doing this crap after it sat for 3 weeks as I had carpal tunnel surgery and could not ride. I have played with all kinds of methods I sea foamed it several treatments. No difference, I jump on the bike in the morning runs like new. 330 in the florida sun get a mile and acts like its running out of gas, I have popped the gas cap, switched to reserve on the start, prime for a few seconds. Same stuff. This week I pull over lite a smoke wait 4-5 minutes and starts chug chug chug then clears out and runs like new again. I have had the bike pee gas out the airbox 3-4 times before, I kind of plan on doing this much http://youtu.be/95nlrP-yn2I

[Jeffintampa]

plus

I am going to try to pull the float pins and clean that hole the needle goes in and put new o rings on it. wish me luck......

[Bonz]

Feel the force working within you. You can do it!

For the needle seat O-rings, if it wasn't mentioned Harbor Freight makes a Viton assortment that you can pick up for under $10.

Here's a tip I picked up on another forum from a Guru, and seems to work based on my first experience with it and needle seats in another set of carbs.

While you have the needle valves out, get some 3M "Adhesive and Decal Remover" from an auto parts store. It's decently high powered stuff, it's basically lacquer thinner but already thinned. I don't know how much you would thin lacquer thinner to get the equivalent, so on your own if you did that.

Anyway, put some on a soft Terry cloth and clean the heck out of the rubber needle valve tips. The small ring that forms on the tip isn't so much rubber being indented, but it is accumulation of a thin layer on all but the ring area over time. At least that is what I have been told, and cleaning with this method removes that thin layer and makes the needle valve viable again. The ring is still somewhat visible, but the cause of the problem is minmized. You can save a bunch of needles with this method if they are otherwise OK.

[Jeffintampa]

Well crap

Well,
Pulled the carbs this am, I pulled out the top 2 the nuts that hold the long thing and the small one in front of it. I pulled the one on the air intake, Pulled the pins on the floats, put new O rings on the thing you clap in the needle rides in, Put new Needles in that hang from the floats. Measured the floats all the same Just a tad above a inch. Soaked the long thing and the 2 others air and small one. Blew them all out and could see in every hole. Put it all back together, gas drips out my air box, ran good for a bit then barley got it back home......running like crap and drip drip out my air box....

[Jeffintampa]

hmm

Pulled the bottom of the air box off and the gas was coming out of *4 carb. Pulled them back out of the bike pulled everything out, Pushed the tab on the float down a tad to help seat that new needle valve?

[Bonz]

No, not what you want to do (bending tab). That will jack you up all over the place with fuel level in the bowl and run like poop.

Get those floats set to the proper height. Not sure what "just a tad over an inch" means in mm speak, tell us the float height in MM so I/we can visualize this. Just because they are all the same height, means zilch if it's the incorrect height. One or two MM difference is substantial

You have a needle that is not seating in the seat or the o-ring on the needle seat can possibly get dinged when seating the seat and let fuel by.

In sense a number of frustrations you are having, but gotta take a step back and get it done orderly.

[Jeffintampa]

float adjusment

That is how you adjust the height of the floats isn't it bend that tab down that needle hangs from down to raise the float. My Chilton says 25.7 mm + - 1 mm or 1.04 in I am reset them all to 1" and a 32nd or a hard inch. One that leaked was shy of an inch

[Bonz]

I meant, don't bend the tab for more pressure on the needle (unless it isnt adjusted correctly to begin with), that isn't the function of float height adjustment (to put more "pressure" on the needle). Something isn't seating/sealing.

It's either the needle not seating in the seat (bad needle tip, bit of debris stuck in the seat, seat itself is marred or scored) or the o-ring that seals the needle seat when you press it in.

I have mangled the o-ring on a needle seat before when putting a new one in, and did catch the issue as it felt weird when I pushed the seat in. Lube the needle seat o-ring once it is on the seat before pressing the seat in (I used a drop oil motor oil) and it should slide in without the chance of damage. Heck, just a dab of spit would work too.