Topic: Float measurement

[mvent]

350F carbs set float at 21mm and when I did clear hose test I'm about 5-6mm below bowl/carb. Should I adjust to get to 3mm below bowl with clear hose ?
Thanks

[Deltarider]

You shouldn't have messed with it. Period.

[Deltarider]

it's not that easy to perform the clear tube measurement resulting in reliable results. Therefore I have posted a method for the oldstyle CB500/550 carbs which is reliable and foolproof. If you tap the same amount of fuel from each float bowl, there's not much chance anything is wrong. I'd had hoped that by now someone would have adapted the same method for the CB350F/400F. http://forums.sohc4.net/index.php/topic,185754.msg2151647.html#msg2151647
What goes wrong, is that people buy a Clymer manual, can't wait to do 'maintenance' and think: hey, that's something I can do. They don't realise that those pages were copied and pasted from other books that dealt with other bikes, that may have had problems with this. Not our bikes. The same goes for turning ignition baseplates and I can go on and on. Stop doing unnecessay 'maintenance' and see if you can make yourself useful by helping your partner in the household.

[newday777]

it's not that easy to perform the clear tube measurement resulting in reliable results. Therefore I have posted a method for the oldstyle CB500/550 carbs which is reliable and foolproof. If you tap the same amount of fuel from each float bowl, there's not much chance anything is wrong. I'd had hoped that by now someone would have adapted the same method for the CB350F/400F. http://forums.sohc4.net/index.php/topic,185754.msg2151647.html#msg2151647
What goes wrong, is that people buy a Clymer manual, can't wait to do 'maintenance' and think: hey, that's something I can do. They don't realise that those pages were copied and pasted from other books that dealt with other bikes, that may have had problems with this. Not our bikes. The same goes for turning ignition baseplates and I can go on and on. Stop doing unnecessay 'maintenance' and see if you can make yourself useful by helping your partner in the household.

Did you get up on the wrong side of the bed?? You aren't being helpful using the added  link=topic=190808.msg2220130#msg2220130 date=1662103527]
it's not that easy to perform the clear tube measurement resulting in reliable results. Therefore I have posted a method for the oldstyle CB500/550 carbs which is reliable and foolproof. If you tap the same amount of fuel from each float bowl, there's not much chance anything is wrong. I'd had hoped that by now someone would have adapted the same method for the CB350F/400F. http://forums.sohc4.net/index.php/topic,185754.msg2151647.html#msg2151647
What goes wrong, is that people buy a Clymer manual, can't wait to do 'maintenance' and think: hey, that's something I can do. They don't realise that those pages were copied and pasted from other books that dealt with other bikes, that may have had problems with this. Not our bikes. The same goes for turning ignition baseplates and I can go on and on. Stop doing unnecessay 'maintenance' and see if you can make yourself useful by helping your partner in the household.
[/quote]

Did you get up on the wrong side of the bed?? You aren't being helpful using the added unnecessary words to make your punctuation pointed finger jab him......

[Kenzo1979]

350F carbs set float at 21mm and when I did clear hose test I'm about 5-6mm below bowl/carb. Should I adjust to get to 3mm below bowl with clear hose ?
Thanks

nah, if you measured 21mm and did it with the float tang lightly touching the spring needle pin without actually depressing the pin, you should be good.

[mvent]

You shouldn't have messed with it. Period.

If I didn't mess with it fuel would still be pouring out the overflow tubes.

[Deltarider]

You shouldn't have messed with it. Period.

If I didn't mess with it fuel would still be pouring out the overflow tubes.

This can have multiple causes. Also the PO - no doubt a reader of this forum - can have had his hands on it. In that case he shouldn't have messed with it.
@Newday777. On the contrary, I've have been very helpful. My method has not yet been disputed. Try it. There's a good chance that after it, you don't have to do anything.

[newday777]

You shouldn't have messed with it. Period.

If I didn't mess with it fuel would still be pouring out the overflow tubes.

This can have multiple causes. Also the PO - no doubt a reader of this forum - can have had his hands on it. In that case he shouldn't have messed with it.
@Newday777. On the contrary, I've have been very helpful. My method has not yet been disputed. Try it. There's a good chance that after it, you don't have to do anything.

You only mentioned you had a tried way but didn't give the link even just blasted him.

[dave500]

as ive said before the float height isnt dead critical,plus or minus a mm or two wont really hurt,when the bike is moving the fuel is sloshing around all over the place anyway,so long as you stop the overflowing.

[mvent]

as ive said before the float height isnt dead critical,plus or minus a mm or two wont really hurt,when the bike is moving the fuel is sloshing around all over the place anyway,so long as you stop the overflowing.

That makes perfect sense

[scottly]

nah, if you measured 21mm and did it with the float tang lightly touching the spring needle pin without actually depressing the pin, you should be good.

The problem with this method is it relies on the spring loaded pins in the needle having a specific strength; if the pin springs are weak, the fuel level will be higher than desired, and if the pin springs are too stiff, as can happen with aftermarket needles, the fuel level will be too low. I had a set of 750 carbs that pissed fuel out of the #2 and #3 carbs, and with the tang barely touching, the measurement was correct, but with the carbs upside down, the weight of the floats completely compressed the pin springs on the two carbs, without exerting enough pressure on the needles to shut off fuel flow. The clear tube shows what is actually happening in the float bowl, without guessing about the strength of the pin springs. 

[Deltarider]

One of the problems with the clear tube measurement is, that for reliable results, you have to wait quite some time (longer than you might think!), with you being in a very uncomfortable position. Hence my solution. The good thing is, once completed, you have also performed the advised seasonal draining of the floatbowls, recommended to remove any possible water or debris. No tubes to be threaded, nothing you can do wrong. As always the method is open for falsification. So far so good.

[MauiK3]

I like clear tube method, gives a real world look at what’s going on in there.
Patience is needed and you have to watch the meniscus in the tube.

[scottly]

it's not that easy to perform the clear tube measurement resulting in reliable results. Therefore I have posted a method for the oldstyle CB500/550 carbs which is reliable and foolproof. If you tap the same amount of fuel from each float bowl, there's not much chance anything is wrong.

How do you know that 50cc is the proper amount of fuel in the float bowls? Did you measure the actual level with the clear tube first, in order to come to this conclusion?

[Deltarider]

it's not that easy to perform the clear tube measurement resulting in reliable results. Therefore I have posted a method for the oldstyle CB500/550 carbs which is reliable and foolproof. If you tap the same amount of fuel from each float bowl, there's not much chance anything is wrong.

How do you know that 50cc is the proper amount of fuel in the float bowls? Did you measure the actual level with the clear tube first, in order to come to this conclusion?

Before it was promoted here, I've done several clear tube measurements in the 80s and the 90s and I found it quite a hassle. I've noticed that even having the bike idle or not whilst measuring could make a difference. My measurements were confirmed (identical) by Marco in Germany. It seems my method is a good starting point. As always it's open to falsification. Please try.

[Quattrocilindri]

it's not that easy to perform the clear tube measurement resulting in reliable results. Therefore I have posted a method for the oldstyle CB500/550 carbs which is reliable and foolproof. If you tap the same amount of fuel from each float bowl, there's not much chance anything is wrong.

How do you know that 50cc is the proper amount of fuel in the float bowls? Did you measure the actual level with the clear tube first, in order to come to this conclusion?

Before it was promoted here, I've done several clear tube measurements in the 80s and the 90s and I found it quite a hassle. I've noticed that even having the bike idle or not whilst measuring could make a difference. My measurements were confirmed (identical) by Marco in Germany. It seems my method is a good starting point. As always it's open to falsification. Please try.

Another caution that I can think of when using the clear tube method is that the bike needs to be parked on the center stand a perfectly horizontal surface. Which would lead me to check it with a spirit bubble level first. Even on my concrete cement garage floor, my level is uneven.  Same would apply if you set your carb bank off the bike on a bench.