Another problem with my 86 VFR 700f

Hey guys so I rebuilt the carbs and got everything reinstalled. It was having some trouble starting at first (Only able to run with the choke all the way down, then dies when pulling on the gas.) So I reset the carburetor to factory specs. Which if I remember correctly is 2 1/2 turns out for all the gas screws on the carb.

Now for some strange reason EVERY time I want to start the bike I have to use the choke (this normal? forgive my ignorance, 1st bike, zero bike knowledge, just basic mechanical skills.) So the bike will start now but runs VERY rich. After turning it on the smell of gas goes everywhere and will even back fire on me at least a couple of times when running.

Any ideas on the tuning of the carb? What the problem is or what the bike needs?

Thanks,

-Adeodatus

 

Did it run before you worked on the carbs?

 

You may have to take the crabs off again to reclean every hole and orifice with compressed air and squirty crab cleaner. I had to do this twice on my CB750 before I got it right and after that got it right for my two VFRs the first try each.
If that does not work you will want to do a fuel delivery test also to see if your pump is delivering the proper flow and look at the fuel fiter if you did not change that out.

 

Toe cutter,

Unfortunately I never tested that. The first time I just cleaned the carbs and never messed with the fuel screws. When reinstalled it would need the choke all the way down just to run. But would die when you pulled on the gas. The second time I cleaned the carbs again, replaced all the filters in the carb, took a guitar string to the jets again, made sure everything was super clean, and then I set the screws to factory specs.

Now every time I want to start the bike I need to use the choke. It will run fine, even drive able, but it runs super rich. I'm guessing that I need to dial back the screws a bit cause of the richness, but I don't get the whole choke problem.

 

I am wondering if you are an unknowing Dynojet victim, air/fuel setting wont cause that kind of over fuel issue.

 

No i didnt use dyno jet. I got factory jet parts from honda. Expensive as hell.

 

You need to have a close look at the sparkplugs to see what their color tells you. As mentioned, could be a fuel pump (or its relay) problem, still dirty idle jets, f'ed-up float level setting, loose jets, air leak past the boots, pluged-up mixture screw passages, more. Pull off the airbox top and filter, then look down the carb throats ( engine running) to see if any liquid fuel is bubbling up under the slide needles, indicating a bad float needle/seat that's leaking.

Problem cdould be related to really poor carb synch or throttle plates not fully closing at idle speed.

You might need to go through the carbs again.

 

Yeah im going to rip it apart again and go through the whole thing.



Is it normal for a VFR to use the choke to start up every time?

 

NO !! Only in low temps. Where u live, about 10 days/year. Could all be related to improperly set float height setting/s.

 

There is a way to adjust float hight?

 

Asking that means you haven't studied the FSM and shouldn't be working on carbs without the Wisdom of the Bible.

 

I got a clymer repair manual and I'm looking at the carb assembly. Don't see anything that would adjust the float hight.

What is this FSM Bible that you refer to?

Suggestion to what I should do to fix my problem would be greatly appreciated.

 

FSM=Factory service manual (the Bible). Far better than Clymer. Download carb pages for your bike from our website and read carefully.

 

ok so im looking at it now. what it looks like i need to do is just take the bowls off and put the carb at a 45 degree angle. Then bend the tang so that all floats are equal and stick out 7mm?

 

Hi
Just my 2 cents but look for cracks in the engine side rubber manifold.

 

Suggest that you measure and record the float levels, not change anything right away, assuming that things aren't that far off unless some fool previously messed things up.

Just a very small change in the tang will make a very large difference in float height.