Mixture Screw Starting Point - # Turns

[CRXSi90]

LOL, I also like that description of the importance of fuel level. But on the other hand, it makes me think that with all these other environmental variables like bouncing down the road, that fractions of millimeters aren't going to cause much of a difference. However, I can see that to get fuel into the air stream of the carb, it has to be lifted ~10-40 mm, depending on where it's going. The main jet is probably the lowest, so +/- 1mm on 10mm is a range of 20% in height that the fuel has to be lifted, so i can see how it would come into play there - I'm a believer. And after all, I'm the one with the bike that's still in parts, and you are the ones with running bikes that have proven success with getting float levels dead on.

[3Phase]

The carburetors are really sensitive about the fuel level in the float bowls and the bike has to be level so you can get the same, repeatable, results when you measure the fuel level in Tokyo or out back of JoeBob's lean-to.

If the bike's not level side-to-side the fuel levels will all wind up different because you'll be setting the fuel level too low in the highest carb and too high in the lowest carb.

If it's not level fore-to-aft the fuel levels will all wind up the same but too high or too low.


At first glance it shouldn't seem to matter how far down into the float bowls the jets sit while you dink with the synch because the amount of lift is always measured from the top of the fuel in the float bowl to the Pilot/Idle, Transition, and Main venturi openings in the carburetor throat.

Then one day you're on the way home from Wal-Mart with a bag full of new tube socks and munching on some beef jerky when something happens and you really need to brake, dodge and flog but not bog. Suddenly you understand why all of the fuel levels should all be the same and not offset side-to-side or front-to-rear and why the fuel jets are placed well below the surface of the fuel in the float bowls; probably should have picked up some new underwear too while you were at Wal-Mart.


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[motoman]

The carburetors are really sensitive about the fuel level in the float bowls and the bike has to be level so you can get the same, repeatable, results when you measure the fuel level in Tokyo or out back of JoeBob's lean-to.

If the bike's not level side-to-side the fuel levels will all wind up different because you'll be setting the fuel level too low in the highest carb and too high in the lowest carb.

If it's not level fore-to-aft the fuel levels will all wind up the same but too high or too low.


At first glance it shouldn't seem to matter how far down into the float bowls the jets sit while you dink with the synch because the amount of lift is always measured from the top of the fuel in the float bowl to the Pilot/Idle, Transition, and Main venturi openings in the carburetor throat.

Then one day you're on the way home from Wal-Mart with a bag full of new tube socks and munching on some beef jerky when something happens and you really need to brake, dodge and flog but not bog. Suddenly you understand why all of the fuel levels should all be the same and not offset side-to-side or front-to-rear and why the fuel jets are placed well below the surface of the fuel in the float bowls; probably should have picked up some new underwear too while you were at Wal-Mart.


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.......and that's about the most livid explanation that'll brush-paint a permanent visual in ones mind!.......have to say though, I DO miss Ivan's intelectual explanations pertaining to these matters...

[3Phase]

Brant, I miss Ivan but he has his reasons for not posting that I can understand and agree with.

I can write intellectually, precisely, and technically too but then folks think I'm a know-it-all arrogant pr^H^Hjerk; get riled up and start to post while the veins in their necks and their eyes are all bulged out and stuff.


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[motoman]

Brant, I miss Ivan but he has his reasons for not posting that I can understand and agree with.

I can write intellectually, precisely, and technically too but then folks think I'm a know-it-all arrogant pr^H^Hjerk; get riled up and start to post while the veins in their necks and their eyes are all bulged out and stuff.


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Already knew that from your visits............and your doin just fine and it fits your style.

[Rasputin]

Ivan? Who the hell is Ivan and why do we care on this site if he is apparently a god on these bikes, but will not lower himself to our standards? Eff him if he thinks he is above the rest of us so far that the sun shines out of his arsehole.
Your god Ivan is nothing to us unless he will willingly participate in our forum.
Much like saying I know a guy who could do the hop skip jump and cover 900 yards while doing it... but can't prove a word.
I know Ivan is a smart dude but...really who cares if he will not descend from his obvious "Throne" to talk to the little people.
Mr. I know it all (ivan)..who I Know reads this forum daily is nothing more than a sphincter muscle in hiding if he thinks we will bend a knee to him.
There is not much that pisses me off more than some scum who thinks he knows more than the collective, but I will give you a point for making his highness's arse front and center once again.
Ivan? Ivan Who?

[IanDMacDonald]

Dang Doug. That's that old-school, baby boomer anger, lol.

[donebysunday]

[QUOTE=CRXSi90;421541]



O-rings...o-rings......I had to think there for a minute. One of my float bowl drain screw o-rings is definitely nasty and all chewed up, but that's not what we're talking about today. The mixture screw o-rings are now more like o-washers as they've been crushed between the two metal washers on either side. But I wouldn't be surprised if they leak a little under vacuum.

I backed them out to 3 turns out now.





You said ,,,,

(The mixture screw o-rings are now more like o-washers as they've been crushed between the two metal washers on either side.)

There should only be 1 washer on top of the little O-rings on the idle mixture screws protecting them from the springs and seating them in the carb body, YOU HAVE 2 squashing those little O-rings ? ? ? Could maybe cause a leak ?

[CaptonZap]

Ras, you off your meds again? Or just having a heat wave up that way?
Sounds like there is a bit of man tube envy in that plaint, as well.
If that is the sort of interaction he would get if he were to show up, I can understand his absence.

Have a good day, CZ

[3Phase]

Ivan? Ivan Who?

Excellent! 9.50!


The Russian judge only gave it 6.66 but I think he used to work at a tractor factory.


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[CRXSi90]

So I appreciate the format of delivery of the descriptions as well. If only for a moment, it puts a smile on my face at times when life and work and stuff are generally frustrating. I'm not one to have my eyes and veins pop out in confrontations, but generally held internally instead. Not sure if that's better or worse, but anyway...........

There should only be 1 washer on top of the little O-rings on the idle mixture screws protecting them from the springs and seating them in the carb body, YOU HAVE 2 squashing those little O-rings ? ? ? Could maybe cause a leak ?

Yes, I have a washer on the top and bottom of the o-ring. Here's what's in the mixture screw hole, from top to bottom:

1. Mixture screw
2. Spring
3. Washer
4. O-ring
5. Washer

I didn't think anything of it because I figured they were counting on the o-ring intentionally being squashed between those washers. As it got squashed, the inside of the o-ring touches the mixture screw, and the outside squeezes out and touches the outer wall.

BUT, after reviewing the tech tip ( http://www.xs11.com/forum/showthread.php?t=38 ), it doesn't look like 2 washers are shown there. I tried to look at the parts diagram for the carburetors, but I don't see anything about the mixtures screws at all! Now that's a little puzzling, but I can see it working fine both ways.

[donebysunday]

So I appreciate the format of delivery of the descriptions as well. If only for a moment, it puts a smile on my face at times when life and work and stuff are generally frustrating. I'm not one to have my eyes and veins pop out in confrontations, but generally held internally instead. Not sure if that's better or worse, but anyway...........



Yes, I have a washer on the top and bottom of the o-ring. Here's what's in the mixture screw hole, from top to bottom:

1. Mixture screw
2. Spring
3. Washer
4. O-ring
5. Washer

I didn't think anything of it because I figured they were counting on the o-ring intentionally being squashed between those washers. As it got squashed, the inside of the o-ring touches the mixture screw, and the outside squeezes out and touches the outer wall.

BUT, after reviewing the tech tip ( http://www.xs11.com/forum/showthread.php?t=38 ), it doesn't look like 2 washers are shown there. I tried to look at the parts diagram for the carburetors, but I don't see anything about the mixtures screws at all! Now that's a little puzzling, but I can see it working fine both ways.

That extra washer at the bottom, well the O-ring is made to seal at the bottom of the carb body into a cupped hole but there is that extra washer keeping it from sealing as it was intended.
I've made these O-rings from the correct sized weed whacker/chain saw fuel line, cut with a razor blade carefully. Don't know if you would get a seal on that O-ring squashed between 2 washers ?
Funny though these extra parts are not easy to come by, why someone would go to the trouble to add an extra unneeded washer ? ? ?
If perhaps the PO had the wrong idle mixture screws ? ? ? Should have spaced them with an extra washer on top of the O-ring under the spring.

[motoman]

That extra washer at the bottom, well the O-ring is made to seal at the bottom of the carb body into a cupped hole but there is that extra washer keeping it from sealing as it was intended.
I've made these O-rings from the correct sized weed whacker/chain saw fuel line, cut with a razor blade carefully. Don't know if you would get a seal on that O-ring squashed between 2 washers ?
Funny though these extra parts are not easy to come by, why someone would go to the trouble to add an extra unneeded washer ? ? ?
If perhaps the PO had the wrong idle mixture screws ? ? ? Should have spaced them with an extra washer on top of the O-ring under the spring.

Knew you'd figure out why only one washer is correct. BTW, that teeny O-ring and washer are N/A from Yamaha, but are available from Suzuki. Part No. for O-ring:13295-29900 Part No. for washer:13291-29900. Another tib-bit of info: the teeny washers are a perfect fit to go under the metering rods if a step, clip position is too much one direction or the other. Makes for a perfect 'half-a-step'. Can be used on the non-adjustable metering rods of the later carbs too, for that half a step richer that may be needed.