Honda VFR 750 RC24 '86 doesn't start after carburetors overhaul

Wow, so far from what the service manual says.

So, long story short, I need to set float height and check the fuel level like in this post of squirrelman

Basically a clear tube mounted on drain holes, then fill carburetors and see if the fuel stops almost in the middle between carburetor’s body and the bowl (the second attachment of squirrelman’s post).

Gonna start with 7 anyway, maybe I’ll reach 9 too

 

I properly set mine to 7mm when rebuilding (on about eight or more 86 VFRs now) and I don't use clear tubing. I have never had flooding issues or dribbling carbs. Bikes start and run as expected and I'm not fouling plugs.

 

From my limited experience, the method of measurement can vary quite a bit. Cap'n has a LOT of experience many of us may not have.

 

I don’t doubt it, but the clear tube testing sounds like precise science to me: so shouldn’t I rely on that?

 

I tend to rely on the method described in the HONDA SERVICE MANUAL for that year and model and has never failed me.



Seeing where the fuel is in a tube in relation to a reference point on a carb body does not bring to mind "precise science" for me. But if it works for somebody, then it works for them and that's cool.

Using a graduated measuring device or precisely created "go" gauge to the manufacturer's specifications sounds more "science-y" to me.

Do what ever you want, as long it eventually gets you to a bike that will start, idle and run correctly.

 

Yes I just bought the gauge showing the service manual at that page, gonna set the float height like shown.
The clear tube test is just “proving” of what is written there, but my first action is just this

 

Opening the carbs I noticed that there was indeed a float much higher than the others... adjusted it and measured with a caliper, but I'll wait for the gauge tomorrow to check them all more precisely

 

Did you ever answer this question? Do you know what I'm referring to?

 

Oh I’m sorry, but I remember I just answered this posts ago.

Anyway no, I didn’t tracked the number of the turns, unfortunately…

 

That doesn't answer either of my questions.

 

LOL ok, now I read that carefully:
Yes, I tracked the parts, and I understand what you referring to.
I installed the new pilot screw with every element (spring, washer and oring), the size is the same, measured

 

the FSM states 2 different numbers for the float height settings, both 7mm and 9mm [after '86] but, unless they want it leaner [9mm] to meet emissions, there is no good explaination why.

i usually set floats to 8mm, and the bikes run well, and i often run a clear tube test to verify my work but not always, occasionally going back in with a small correction followed by another tube test to be sure.

 

Floats set at 7mm, this is my clear tube test: am I good?

 

I have no idea, but this repair is interesting... in good way.

 

LOL I didn’t do it, already found like this

 

I tried to start it, the bike seems to start, but then it stalls. I checked for fuel leakage from the needles but there's none. Now, the battery is drained and I'm recharging it.

I set the mixture screw at 2 turns,
never applied throttle,
always choke on.

Any advice?

 

If your idle adjust screw is set way too high or way too low, it'll make starting it difficult. Make sure it's not cranked way in after the rebuild.

 

My idle adjust screw is set at 2 turns, is that too high or too low?

 

Every bike has it's own personality. Try some different combinations. Try less choke. No choke. Try a little throttle just at the right moment.

But I still suspect something that was missed and / or not adjusted properly is the most to blame here. Not trying to be harsh, but the fact that when you took the carbs back off and apart you found a float setting / adjustment WAY off is not confidence inspiring.

Keep on keepin' on.

 

Terms. Cold is referring to your IDLE ADJUSTMENT. As in the black nob. Not your pilot screws.