Whats the Carbs fuel bowl amount??

[loopsandlogic]

Would anyone have the fuel amount that the carbs bowls should hold??

I'm trying to see if I'm having a fuel level problem.

I'm getting stumbling all the way from 5k and up.

Also, I've narrowed it down to the carbs....either there not lifting the carb slides which would indicate my diagrams are torn, or my main jets are clogged which were recently cleaned.

Its an 84' VF500F.

Any help is appreciated.

LL

[loopsandlogic]

Bump please

[supervfr]

I was hoping to know the same thing.

[NorcalBoy]

I know it isn't helpful to answer a question with a question, but, is there a specific reason as to why you need to know this?

The float bowl will hold as much fuel as is allowed to enter when the float is set to the correct height and the components are functioning properly. The float height determines the amount of fuel in the bowl. Of course the outright max volume of fuel it will hold is determined by how much you can put in the bowl before it comes out the overflow.

[loopsandlogic]

That's right. Cause if I'm running lean at top end like I know I am, because of the lunging, then I need to know how much each bowl should be holding.

I'd rather not take my carbs off again and take the bowls off....risking the bowl gaskets not sealing on me. Honda wanted a arm and a leg just for those seals.

I just hope it's not my diagrams....

It almost sounds like there bouncing around after 5k rpm.....???

Any test to perform on the diagrams??

At least I don't have to take the carbs off just to access those

I'm hopping someone will chime in here...

LL

[loopsandlogic]

Also, my pump is working perfectly... a tad over 700cc's per minute.

Fuel deliver is perfect....but fuel to motor is skeptical...

Thank you

LL

[squirrelman]

not a useful question because the difference between proper fuel quantity and wrong is too small to measure accurately.

just experiment by raising or lowering float levels after studying the service manual: yes, i do know what a pain it is getting carbs on and off!

[loopsandlogic]

It's not so much as taking off the carbs, but the fact of the price of carb bowl gaskets!!!

It's not even funny

I just need to know what the common amount of fuel for a carb bowl would be for a properly working VF500.

If someone would just take the time to drain just one carb from there perfectly running vf500, I could see if my carbs are in the ballpark.


Any tests that I could perform on the diagrams??

If the bike can rev up to 7k and above, is that an indication of sticking venturi slides??

I've been working on carbs, cars and bikes for years (since I was 13 years old), but never have I've come across this problem.

I kinda feel like an

LL

[woody77]

If you pull the airbox, you should be able to see all four slides, right?

You should be able to tell if they're moving up/down correctly by watching them while cracking the throttle.

On other bike I know you can test the slides just by blowing air into the slide's vent to the outside world (simulates the vacuum under the slide).

And quantity isn't going to tell you anything, unless you're getting nothing out. Specs on the floats are in 1/10ths of a mm in level. Spill a couple drops and you're WAY off.

[loopsandlogic]

They shouldn't be jumping....correct?

They should level off at certain rpms??

Again, I'm not taking the bowls off. Yes I understand that this way of checking the fuel is not the best way of doing it, but it will give me a ball park.
And that's all I'm looking for.

If someone tells me there getting this much, and I'm getting 1/16 oz, 1/8 oz, less.....than I would suspect something is way out of adjustment.

If everything else fails, then the bowls will have to come off....

[squirrelman]

hey, are you assuming that float bowl gaskets need to be changed every time ??>

not true, and cheap gaskets can be obtained through a company called "K & L Supply"

why not just check the fuel level inside carb by means of an external clear tube in traditional fashon???

[masonv45]

If someone would just take the time to drain just one carb from there perfectly running vf500, I could see if my carbs are in the ballpark.

That's not gonna work as the fuel in the fuel tubes will flow into the first carb you drain. Now if you measured the second carb, that would probably give you an accurate volume.

With the airbox off, reach inside the velocity stack and GENTLY push the vacuum slide up into the bore. Now let go.

If the slide "SNAPS" down, you have a ripped diaphragm or it is not seated correctly.

The slide should come down quickly, but should not "SNAP" down.

When running, the slides will kinda jump as the airbox is not on to provide a baffle to even out the air pressure.

To test the float height:
- Take a clear piece of tubing and attach it to the drain port of a carb.
- Turn the open end up so the tubing forms a "U" shape.
- Short the fuel pump to fill the carbs.
- The top of the gas level in the tube shows where the top of the gas level is in the float bowl.

Do this for all 4 carbs. They all should be the same.

Note, when setting the float height, did you ensure that the metal tang from the float "DID NOT" depress the pin in the float bowl needle? If not, then you need to pull the carbs and rest the float height again.

Also, the throttle position determines the fuel circuit being used, not the RPM.

If you have a fuel pump, placing a fuel filter after the pump may cause a "false pressure" in the line that the fuel pump cannot overcome, starving the carbs in high gas-flow situations.

[supervfr]

Thank you mason for the information.

I am curious tho, how can i tell where the fuel level should be?

[masonv45]

I've been looking for that online and can't find it.

I know I've either seen a picture of it in one of the 5 manuals I've got - or somewhere on the web. I'll ask around.

[supervfr]

Your help is appreciated. I might give honda a call tomorrow and see what they say about it.

[loopsandlogic]

I'm gonna test the slides a.s.a.p.
And your idea for the clear hose and height being equal for all 4 carbs by the bowl is a good idea. Now all I have to do is find some clear hose ; )

Tried K and L at my shop...they said they no longer carry them for the VF500.
And really, the bike is pretty old....I wouldn't want to take the chance of them going bad after I've put everything back together.


Quote:
Note, when setting the float height, did you ensure that the metal tang from the float "DID NOT" depress the pin in the float bowl needle? If not, then you need to pull the carbs and rest the float height again.

I'm not quite understanding you....could you elaborate any further??

And the fuel filter is in it's original place. But you brought up a good point....???

Will post back after further tests.

LL

[supervfr]

Im still a little big confused. I knwo how to do it. However how do i need to know where the level should be at. I can find the level, but how do i know if it is too much or too little?

Thanks

[loopsandlogic]

Well, after testing my bikes sync' (right on!!) I've come to the conclusion that I need to see where I'm having this small lunging/lean problem at throttle positions.

But, since Ohio is sooo cold (low 30's) I'm pretty much stuck! : |

And, I've been looking online, but know where do I find what throttle position the pilot jet plays in this....

Anyone know??

And I'm very confident that my cams are set properly. Because if they weren't, I'd be having acceleration problems at all RPM's. Thanks for the info on that Daughtry ; )

Thanks

LL

[supervfr]

are you sure that the carbs are clean. with old bikes like ours thats pretty much the biggest problem.

[loopsandlogic]

Yeah I'm sure...each jet was taken out and blown through, followed by the passages.

I was thorough about everything.

I kinda wish it was the jets, but I'm confident...... : (

I'll figure it out, if this weather would break....but looking ahead, this season is over with.

I guess I'll be posting sometime during the spring again after my testing.

She'll be up and running in tiptop shape in no time....no worries.

Thanks everyone...you guys rock!!!!

LL

[supervfr]

question for ya. are the passage ways through the carb called circuts?

and are they interconnected? or each jet passage separated from the rest.