VF500 Carb Sync Question ?

Hi All

I have a question you guy's could answer. I have been syncing the carbs on my VF500 and have nearly got them all level on my Morgan Carb tune balancer.
But something's niggling at my brain saying somethings not right. When i pull the tube on no 2 cylinder and leave the vac port open the rev's go up but on all the rest the rev's drop slightly when i pull them one at a time.
Its seem to rev ok and drops back down to tickover ok. It needs a good blast but not possible yet as plastics away for spraying.
One other thing when i have replaced all the vac ports and its ticking over quite well, if i start to cover the air intake on the air box the rev's again will rise but die as i cover more of the intake. Saying to me mixture not right at tickover but where ?

thanks Dave UK -----snowing

 

Is number 2 (the one where you pull the rubber hose off the base carburetor?)

If you adjusted the other three adjusters where the bars all line up, and stay uniform as you rev the bike, your pretty much done. I have a Morgan Carb Tool too, :smile:

Cheers, no :smow: here, just sunshine

 

seems mixture screws might need better adjustment ?

 

Good thought.

 

The manual lists initial settings
(not necessarily optimum) for idle mixture screws where they're OK but not fine-tuned for whatever variations in cylinders, temperatures, needle shapes, or carbs might cause at around idle speeds. Perfect work for a gas analyzer if you're a perfectionist ! EPA wuz protecting us frum gagging on our own exhaurst fumes, so bikes were weak just above idle, and usually run better with the screw from 1/2-1 turn opener.

 

FWIW, I adjust the idle mixture screws by measuring exhaust temperature at an idle speed just above normal using an IR thermometer, works well for me.

 

I use my IR thermometer for cooking too :tongue:

Nice how prices came down on those things...Now, every garage and kitchen can have one...

 

Cheers Guys

Got one of those IR temp things at work, will give it a go when next in the cold garage

Are the mixture screws on my 1986 model behind the blanking plates or are they lurking somewhere else ?

Dave UK

 

i own a 84 500 and im rebuilding my carbs but have some questions. posted once before with info but no responses?? here are some pictures ive done all the vavle adjustments and ready for the lst and been told not so fun job of finishing the carbs

 

What are your questions?

 

The best carb sync method that i've used was based on this, Making a $5 Carburetor Balancer - YouTube
I made mine with 4 soda bottles and some small valves I picked up at the local fish tank supply shop ...this is very sensitive.

Breastfed

 

well i have some questions about adjusting valves. carbs work

 

what are the jets on a stock bike 84 interceptor vf500 i have pipes on it. thats the only mod.