Float height adjustment

[ruffrider]

This may seem like a silly question but the clymer manual that I'm using doesn't tell me if the float needles should be seated all the way or just the weight of the floats resting on the tabs for adjustment. Do I seat needles then measure 25mm or leave them just resting???

[prometheus578]

'I need a rest."

Just resting. No pressure.
The float needles are already seated all the way. The weight of the float does not compress that little springy thing.
Best as I can figger it.... that little springy thing act as sort of a shock absorber.
As the bike uses fuel and the bowl refills... as the bike twists and turns and the fuel level rises and sloshes... were it not for the "springy nipples" on the needles(I like that term!), the float adjusting tang would eventually bend, throwing off your float height measurement.

[ruffrider]

Thanks! That's what I thought but wanted to be sure. Thanks for the quick reply.

[prometheus578]

"Oh, and welcome to the site."

Also, there is some confusion concerning measuring the float height. It is measured with the bowl gasket in place on the carb.

[ruffrider]

Wow is that good to know cuz that a considerable difference... at least a silly milimeter or so. Thanks again, Prometheus

[randy]

Also, there is some confusion concerning measuring the float height. It is measured with the bowl gasket in place on the carb.

Prom, get another cup of coffee.

All the manuals I have say to measure without the gasket in place.

[Ken Talbot]

Just to toss in another perspective - I've always felt it does not really matter if you measure with or without the gasket, or whether you hit 23 or 24 or 25 mm, at least not the first time you do this. The first goal is to get all four floats exactly the same i.e. within 0.5mm of each other, closer if you have the patience. Then you put it all back together, do a thorough sync/colortune/resync, and ride it for a short bit. Next, you check performance, look for flat spots, do a plug chop to check plug color, and check fuel consumption. Only after all this, can you go back and figure if your floats need to be set higher or lower.

IMHO, chances of hitting it dead on the first time by setting to a number in the shop manual is a long shot, considering all the variables that come in to play with a 30 year old motor, altered exhaust, monkeyed-with jets, modified air filters, etc, etc.

YMMV...

[AlanB]

hi Ken,

Very difficult to put it better..........

AlanB

[prometheus578]

I am in Randy's debt."

Now that's odd....
Not the part about being in Randy's debt, though t'is quite an oddity, but that I am mistaken.
How can this be?
Truth be told, I've always measured from the bowl "Without" the gasket in place. But, as there has always been some debate upon this point, a few days ago I went on a self search for answers.
The Clymers was too vague..."Measure the distance from the bottom of the float to the float bowl gasket surface." Poorly worded, at best, and one can see the cause of the confusion.
I next checked the Yamaha service manual. Somewhere, though I cannot find it now, I found an equally vague instruction which, at the time, seemed to reenforce the measure from the gasket idea.
What, there it is... Page #4-3, "B" specifications:
Float height: 25.7mm +/- 1mm (above gasket surface).
So, to my addled mind yesterday... It seems that all has been decided then. Keep the gasket in.

Yet, here comes Randy with his "Prom, you're an idiot" attitude.
Ok, tough guy.... I know what I read. I can read between the lines and infer stuff, etc.
I'm typing a reply when I stumble upon page #4-5... and there it is, in black and faded yellow white....
Float level adjustment....:Measure the distance from the bottom of the float to the float bowl gasket seating surface without the gasket."
How I missed seeing that yesterday, I'll never know.

Ok... All praise to Randy, for helping confirm something that some of us already knew and some were undecided on.

Now, don't everyone go jumpin' on ol' Prom...
Thing like this happen.... even with proceedures that one feels are common sense.
One will find differences in measuring float height between different brands of bike.
Ruffrider's question about the needle's spring/ press down on the float isn't so silly.
On our carbs, the float height is measured with the carbs turned upside down. On other carbs, one tilts the carbs at an angle, so that the float tang just "touches" the spring loaded rod on the needle.

But, coffee does sound good right now, Randy.

[79XS11F]

Re: "Oh, and welcome to the site."

Originally posted by prometheus578
Also, there is some confusion concerning measuring the float height. It is measured with the bowl gasket in place on the carb.

It is confusing but ... the measure is to be taken with the gasket removed. This is for the 1978 model from the factory manual ,section 4-4 on carburetor adjustment.
"Measure the distance from the bottom of the float to the float bowl gasket seating surface without the gasket"

Rob

[jjwaller]

Is it just my carbs?

I've tried the measurement method on the Mikunis and I always have to use the sight tube method to get them dialed in. Measuring the floats on mine has no relation to reality. Just curious, are my floats really that mangled? Honest, not me.....The PO. That's my story and I'm sticking to it!

[SFerinTEXAS]

I also use the sight tubes as a standard rule. Best to know than to expect.

[DiverRay]

SFerinTEXAS:

I also use the sight tubes as a standard rule. Best to know than to expect.

Grasshopper!! Once you have attained the proper state, you will be able to dial in the carbs with the float height!
It's all a matter of experience. After a few sets of carbs, they get easier to adjust. Just ask PROM, IF you dare!

[SFerinTEXAS]

No offense DR but i do believe in what I can see. A while back I was cleaning extra brass floats and put 8 in the carb cleaner pot . Got distracted and forgot them for a few weeks. When I pulled them out 4 had taken on fluid. The leaks could be so small that a short soak may not have shown the problem. Maid me wonder about the ones I didnt test so long before. Using the modified grease fittings it only takes a few minutes to double check. BETTER TO SEE THAN EXPECT. With all do respect.. Sorry I missed you when you came to get PATHFINDER. I was not Worthy

[ruffrider]

Jeez, look what I started! No really, I enjoy all the friendly banter and good tips on this forum. Thanks to all. I hope my good buddy "The White Buffalo" who left me his 79 special is smiling down from heaven enjoying my journey. Any ideas where to get a float bowl screw plug with a tube so as to attach a clear hose?(Maybe the plumbing supply at the hardware store.) What I really need is a lot more time. Damn job gets in the way.