WE KNOW IT'S NOT IGNITION .. CHECKING CARBs

[randy]

Rob,

I sure hope that's it. I would have thrown the bike off a cliff by now.

[79XS11F]

Originally posted by randy
Rob,

I sure hope that's it. I would have thrown the bike off a cliff by now.

NOW NOW .. We don't throw "the best bike ever built" off a cliff lol lol

UPDATE

THE BIKE HAS NEVER RUN SO WELL.
PURRING LIKE A KITTEN.



THANK YOU EVERY ONE WHO HELPED WITH DIRECTION AND TIPS.

Rob

[underdog57]

Yippeee

Great to hear it !!!
A kitten with a growl I bet

Bob

[79XS11F]

Yes she is pulling good with no misfire at constant RPMs. I took her for a quick 5 KM run and all "seems" to be good to go.
However they are calling for 2 days of rain now :-(
Rob

[underdog57]

I look out the window for weather here , its changes every five minutes !!
Have a great time with the Bike !!

[TopCatGr58]

Final SUCCESS!

Hey Rob,

That is AWESOME news!!! You had many of us pulling our hair out trying to figure this thing out! Again, just goes to show how critical good carb cleaning and settings are to the way these things run!

Hey, get a rain suit.
T.C.

[mro]

"79XS11F" new carb tech!!!

Imagine you know your carbs intimately now

No rain suit?
Give ya time to vac sync and fine tune fuel/air mix


mro

[79XS11F]

Re: "79XS11F" new carb tech!!!

Originally posted by mro
Imagine you know your carbs intimately now

No rain suit?
Give ya time to vac sync and fine tune fuel/air mix


mro

I did the vac sync before the test run. I will however re-check it this weekend or when I add the pods and header pipe.
I can now go back to working on my hop up engine. All the time I spent on this issue I could have had that engine ready to go into the bike.
I do however have to turn the idle down. after I got the engine up to full temperature she was idling at just under 1400 RPM. I also think she is still running a little rich but the pod filters and new used 4 into 1 header should fix that.
Rob

[79XS11F]

SPOKE TO SOON

SPOKE TO SOON. OK when I went to use the bike this morning it behaved poorly untill well warmed up. I smell gas when standing beside it. Somehow or another gas is getting into the system PAST the float valves and flooding the system when the bike sits for any lenght of time. I know the fuel tank valves are in deed leaking about a shot glass each over night but that gas should still not get past the float valves .. right?
So anyway I did used the bike and once that excess gas was burned off it ran fine and still better then before I detaled the carbs. I did confirm that the valves were closing air tight several times before installing the carbs last night. Could the brass floats be floating at different levels at random times. OH bike was on main stand over night.
Any ideas on cause and correction?
Rob

[randy]

Rob,

I hate to belabor this point, but the reason your floats don't all float the same is probably becuase they have leaks in them. Some of them are sinking.

[skids]

Re: SPOKE TO SOON

What is the "Main stand", the centerstand? If so, you could be encouraging oil contamination with your gasoline leakage. The centerstand raises the rear wheel/tire off the ground and puts a foreward slope for drainage towards the cylinder head.

Park the bike with front pointing up-slope, and bike on the sidestand. Pull off the airbox. In the morning, see which carb shows drainage towards the inlet of the carb.

You ARE using inline filters, no?

You can recondition the petcock seat with some metal polish. There is a conical section that the diaphragm-plunger seats against. Also, check the Oring. Check the holey gasket and replace if necessary. Take the handle valve and flat sand the face with fine emery paper, followed by metal polish to attain a mirror finish. This will help make the holey gasket last longer. When you reassemble, recondition (bend) the wavey washer so that you get good contact pressure of the valve anainst the holey gasket. The sectioned oring that seals the tank may give you some trouble if it is squashed. I have rejuvinated those by cleaning them in hot soap and water and soaking them in mineral spirits.

[79XS11F]

Originally posted by randy
Rob,

I hate to belabor this point, but the reason your floats don't all float the same is probably becuase they have leaks in them. Some of them are sinking.

Hey randy .. The floats are dry as a bone and light as a feather every time I have taken them out. There's also no noise in them at all when I shake them.
I also don't "think" their hanging up on the sides of the bowls and they move very freely on their pins.
Is there any other fuel circuits in the carb that could allow fuel to get by the main float valve??
Rob

[79XS11F]

Re: Re: SPOKE TO SOON

Originally posted by skids
What is the "Main stand", the centerstand? If so, you could be encouraging oil contamination with your gasoline leakage. The centerstand raises the rear wheel/tire off the ground and puts a foreward slope for drainage towards the cylinder head.

Park the bike with front pointing up-slope, and bike on the sidestand. Pull off the airbox. In the morning, see which carb shows drainage towards the inlet of the carb.

You ARE using inline filters, no?

You can recondition the petcock seat with some metal polish. There is a conical section that the diaphragm-plunger seats against. Also, check the Oring. Check the holey gasket and replace if necessary. Take the handle valve and flat sand the face with fine emery paper, followed by metal polish to attain a mirror finish. This will help make the holey gasket last longer. When you reassemble, recondition (bend) the wavey washer so that you get good contact pressure of the valve anainst the holey gasket. The sectioned oring that seals the tank may give you some trouble if it is squashed. I have rejuvinated those by cleaning them in hot soap and water and soaking them in mineral spirits.

No I don't have pod filters on it yet and will not install them until this is fully sorted out. I will have to do the park on a slope thing and see what's going on. I will check my oil for gas contamination as well. I don't need that kind of trouble.. I have enough trouble already lol lol. I was going to replace the fuel valves with new manual ones. Seems like an easy fix. However even if they were not leaking there would be fuel in the lines from the tank that would still get into the carbs. I just don't understand how it's getting into the carbs when the float valves are sealing. i think new floats are also in the picture real soon.
Rob

[79XS11F]

Can someone tell me if these are the correct plastic floats to buy from Mikes XS

http://www.mikesxs.com/mikesxs-fuel_...ategory_id=4.2

Part #20-6502

about 1/2 way down the page.
says
Plastic Carb Float - Fits: 1980-84 XS650 Stock 34mm. Mikuni CV Carbs.
Also replaces Brass float used on early 1980 650 "Specials".
OEM Ref.# 3H5-14985-00

thanks
Rob

[Douglas Money]

Just slightly off theme. Is there anybody in the chicagoland area that would be interested in (helping) showing me how to do my carbs? I am planning this during the off season. Thanks.