Topic: 550K0 mixture screw setting

[DH]

When syncing and balancing the carbs on my 550, The spec for the air screws is 1.5- 2 turns out (clymer).
The engine runs its smoothest, at idle, with them set to 1 full turn out. Any insight? Would it hurt anything to run them like this?
Lean mixture (for whatever reason) cause this condition?

[Deltarider]

Would it hurt anything to run them like this?

I suppose not. Honda Shop Manual CB500-CB550, p 138 prescribes 1¹/₂ ⁺/_- ³/₈ turns out, so...

Lean mixture (for whatever reason) cause this condition?

Possible airleaks are O-rings between manifold and engine and/or split rubber boots. Are your carbs standard 022A? How does your bike accelerate?

[DH]

It seems to accelerate ok, just won't idle well with screws adjusted out more than 1 turn.  No leaks as far as I can tell.
I wondered about the float level too low.  Did the clear tube method, and was set maybe a little lower than 4 mm. to avoid 
possible overflow, but not severely low.  This is sort of a nit-pick rather than something catastrophic. I checked the 500/550
factory manual here on the board and it listed the screw adjusted to 1 turn plus/minus 3/8 turn out from seated. (page 9, sec 3
maintenance operations section). The carbs are 022a. completely stock everywhere else. I have done the necessary other services
It seems extremely cold natured, and I know that is normal to a degree, maybe I'm just not used to it compared to the 750.,
But I have to really stay with it till its warm.


http://manuals.sohc4.net/cb500/service_manual/HSM500550_1.pdf

[Deltarider]

As a rule of thumb: do not bend the little floattang. If floatlevel is not correct, there may be something wrong with floatneedle/valve but not likely the floattang, unless it's been messed with ofcourse.
Usually the 500/550s idle nicer and nicer (and higher in rpm) the more the airscrew is turned out. I don't recommend this because the bike will not accelerate well. Yours behaves opposite. When you're at it you may unscrew the slowjets. They tend to gradually close because of dried gas residue.

[DH]

As a rule of thumb: do not bend the little floattang. If floatlevel is not correct, there may be something wrong with floatneedle/valve but not likely the floattang, unless it's been messed with ofcourse.
Usually the 500/550s idle nicer and nicer (and higher in rpm) the more the airscrew is turned out. I don't recommend this because the bike will not accelerate well. Yours behaves opposite. When you're at it you may unscrew the slowjets. They tend to gradually close because of dried gas residue.

I will keep that in mind and use a more proper tach to set idle. I tend to set idle too low sometimes.

[Deltarider]

Aaahh... I once worked on a CB550K3 that indicated 1400 on its tach where real rpm was 1000.