80-81 carbs without the pilot plugs

[donebysunday]

Hi XSives !

I've the later carbs on my 81 LH without the plugs in the pilot jet tunnels. I've adjusted the floats as high as I can, 23mm and yet checking the fuel level on or off the bike I can only get the fuel level to about 1/2" below the top of the float bowl. Is this OK ?

Side note: My local dealer mech says with the 4-1 and pod filters to go up a step on the pilots and 2 or more on the mains. Just installed 45 pilots and 120 mains in place of stock.

Thanks So Much ! Don };~)

[motoman]

Hi XSives !

I've the later carbs on my 81 LH without the plugs in the pilot jet tunnels. I've adjusted the floats as high as I can, 23mm and yet checking the fuel level on or off the bike I can only get the fuel level to about 1/2" below the top of the float bowl. Is this OK ?

Side note: My local dealer mech says with the 4-1 and pod filters to go up a step on the pilots and 2 or more on the mains. Just installed 45 pilots and 120 mains in place of stock.

Thanks So Much ! Don };~)

Not sure what your doin' wrong, but 1/2" below top of bowl tells me your static float setting is more like 31mm. That 23mm setting will put your running at idle fuel levels just into the casting above the lock washers. With that carb bank UPSIDEDOWN, gasket removed, your floats need to go DOWN, not up. The other issue you may be having is the measurement is done at that highest point of bottom of float, not at the metal tang. Bettin' that's your measuring issue. You definitely would'nt be the first with the measuring location. Whatever you choose to do the measuring with, be sure and do same method on all four, so at least they are all the same. Slide dial indicator works the best, just convert mm to inches, set and lock indicator, stand vertically and set ALL eight floats so dial indicator just ever so lightly scuffs the bottom of float not moving it. Hope that helps. BTW, every millimeter of float change equals approx. 2.5mm of actual fuel level change.

[donebysunday]

Thanks Man !

Going through my manual I picked up a fact that using 1/4" fuel line was causing barometric pressure to push the fuel level back down giving me a false reading.
It said use a fuel line that is no more than .10 ID, I adapted a 1/4" down to a .10 by simply sliding the smaller line into the larger, perfect fit. Tried it on the #1 carb and same reading 1/2" below the top of the float bowl. Then I noticed a kink in the 1/4" fuel line just where it was on the float bowl nipple, let a little slack in the smaller line and perfect fuel level, about 3/8" below the top of the bowl. Then I dug through my carb stuff ( I've done over 100 sets of XS650 carbs) and found my very flexible clear yellow line I always used on the 650s. It made the bend without kinking and showed the same fuel height in the bowls as the .10 line. All is well !

On to the next fix. 2 of the float bowls had a steady 1 drip per a few minutes from the nipples. The float bowl needle plug was not sealing ( new on order) but in the next few days I want to take advantage of a warm streak and check the bike out again. I tapped the nipples with 6/32 and installed tiny screws, hope this stops the leaking and the carbs can go back on ASAP.

Thank You ! Don };~)

[skids]

I really doubt that the hose size makes any difference for a static reading. The same pressure is exerted on the fuel pool in the carb bowl, thereby cancelling its affects.

[donebysunday]

I must agree although odd readings at first my last test between the small line and the soft 1/4" line would prove the manual wrong ?

Thank You ! Don };~)

[skids]

I must agree although odd readings at first my last test between the small line and the soft 1/4" line would prove the manual wrong ?

Thank You ! Don };~)

Well, there must be something with the physics that I must not be considering. Any fluid mechanics out there?

[Rasputin]

I am not a fluid mechanic But I do know that any fluid will find it's own level from any spot to any spot. All barometric pressure works on both the carbs and the fuel tank. So nope, any differences in level would not be attributable to fuel line size.

[petejw]

Hi XSives !


Side note: My local dealer mech says with the 4-1 and pod filters to go up a step on the pilots and 2 or more on the mains. Just installed 45 pilots and 120 mains in place of stock.

Thanks So Much ! Don };~)

u might find the jets uve put in might be to big,
if the bikes sluggish and the spark plugs are fouling up
id drop the pilots back to stock and run 115 mains
this was the set up i ran running pods and a 4 -1.

[donebysunday]

Hi Pete !

More testing is needed, it gurgles at steady rpm in lower gears just around the hood so at this point I think your right.

Also when coming to a stop sign rpm slows to the point of stopping, I think the fuel level to high as I had this on my XS650s was to high of a fuel level in the bowls.

So off come the carbs once ,,,,,,,,,,,,,, more ?

Thanks ! Don };~)

[petejw]

Hi Pete !

More testing is needed, it gurgles at steady rpm in lower gears just around the hood so at this point I think your right.

Also when coming to a stop sign rpm slows to the point of stopping, I think the fuel level to high as I had this on my XS650s was to high of a fuel level in the bowls.

So off come the carbs once ,,,,,,,,,,,,,, more ?

Thanks ! Don };~)

sounds like its rich, drop the pilots back to stock,
check float heights, should be 23mm.

[donebysunday]

Pete You Nailed It !!!!!

Now I have what feels like my new or nearly new 79 XS1100. Just love the way the front comes off the road in second gear. This 81LH scares me like I remember when I was 27 on the 79.

Added a cup of DURA LUBE to the oil, shifts much nicer. Also cranking it over in gear a couple rounds to free the clutch, ( keep the front brake on, don't ask ) helps with that stuck clutch cold start first gear snatch.

So 42.5 pilots, idle mix screws at 3, 120 mains and floats set at 23. Goes right on past redline unless you stop it !

Warm spell 37F here been playing with it since 10AM, put it away about 3PM.

Thank You Pete and all ! Don };~)

[petejw]

great stuff,
glad i could help u out :-)

[donebysunday]

Thanks Pete !

Much to be sorted out, yet to make a longer slab run. Weather turned and I was lucky to get what I did get done.
I'm more sure and steady on this big old 81 XS1100LH than I am on my 83 XS 650 ? eBay # 160951357137

Thank You Pete ! Don };-)

[fredintoon]

- - - I'm more sure and steady on this big old 81 XS1100LH than I am on my 83 XS 650 ? eBay # 160951357137 - - -

Hi Don,
only in a straight line.
Beware the first corner you take the XS11 into like you were on the XS650.
Lucky you that nobody bought the XS650.
Seller's remorse can be a heartbreaker.

[donebysunday]

Hi Fred !
You are right, I member the 79 XS1100SF after trading in my 77 650D in Maxi Maroon with matching redline on the Dunlap racing tires. Needed much more muscle to get it through turns. Then came the Radian 600 that only needed you to think, almost no effort. No I have not sold the 83 XS650 SK it's so much fun but the 1100 is scary fun and a much better long distance machine !
What to do ? ? ? ? Don };~)