Need Help setting Float Level. 2nd Gen VFR750

So the plan is to install the front boots and place the rear boots on (lightly) and tilt them upwards?
Then install the front carbs firmly into the boots, and push down on the carbs, hopefully seating the rears in the process.

Pretty much what I did from the beginning...(following JamieD's how to on his website)
Daugherty Motorsports - V4 Honda Carb Removal and Installation Procedure

...hopefully newer carb boots will help.

Trying again today....bringing a portable heater and a 1600 lumens trouble light.

 

If would try tilting both the front and the rear boots as shown in the sketch. This is the Factory method for all Honda V4 carburetors.

To understand why this works you need to keep in mind that the spacing of the carb throats is slightly wider than the spacing of the engine's intake manifold at first.

By angling the boots (both front and rear) this allows you room to push the carbs straight down and as the carbs move down the throats seat and align with the engine's intake manifold.

It is an easy two step process. No mallets required.

 

So I got the carbs installed...it took a very long time. we really had to pry those rear boots open and really push in hard. Chewed up the boots some but I don't think enough to cause any issues.

Anyways....put the airbox and tank back on...put about 5 litres of fuel in it. Cranked the bike a bit to get the oil pressure up and then tried starting it.

After about 5 minutes of patient attempts (short starter bursts followed by some waiting) the engine started to sputter to life...a little persuading with the throttle it started, but I had to keep it running by holding on to the throttle.

After a few minutes of idling it was able to hold an idle with the choke off but it was rough and way too low...I didn't want to adjust the idle until the temps were at operating range.

Took a short video:
[video=youtube;S4RL222F5dk]http://www.youtube.com/watch?v=S4RL222F5dk[/video]

It sounds a bit rough. When it gets warmer I'll do an oil change and take her for a spin.....hopefully all it needs is to be driven a bit and maybe get some fresh plugs.

 

Every time the carburetors are removed and reinstalled they need to be synchronized with a manometer. No shortcuts here.

 

Lame.

My next bike is gonna be FI

 

Respectfully, I don't think of carburetors as being lame. The V4 CV carbs are pretty amazing pieces of engineering. This said, I certainly understand some of your frustration given the installation snags you've run into.

I would recommend purchasing a manometer and synchronizing the carburetors yourself. This tool will pay for itself very quickly when compared to the cost of having this service done at your local shop.

http://www.carbtune.com/

 

Thanks for the link IC.

...and for the record I don't see the carbs or the bikes as being lame....but the fact that the carbs were synch'd just this last fall and that they need to be re-synch 'd everytime the carbs are removed....well that's lame.

I gotta find out how easy it is to synch the carbs...the bike is becoming quite the time and money pit.

 

Bah!!

I just read over the carb synch procedure in the manual...I have to adjust them from the Pilot Screw?!

Ugh...I gotta get a carb synch Manometer and a pilot adjustment tool.

Hmmmmmm

 

For clarity, the synchronization adjusting screws are underneath. The pilot screws are on the side.

The synchronization adjusting screws are difficult to reach unless you have the Factory tool or have fabricated something similar to this. The pilot screws are easy to reach with a long slotted screwdriver.

 

Really?!

The Honda service manual states the synch procedure involves turning the pilot screws until all carbs are close to each other.

 

To adjust the pilot screws (these are fuel screws, meaning out equals more fuel) - going from gently seated, turn them out 2 turns. With a warm engine turn out slowly and listen for an idle increase. Set all the same and you are good to go. No need to follow the Idle Drop procedure, IMO, as this actually negatively affects performance.

To synchronize the carburetors use the Factory tool (or similar) to turn the synchronization screws while carefully watching the manometer. The goal is to get the manometer column readings to be as close as possible so that all four carburetors are equally balanced.

It is amazing how much a difference properly synchronized carburetors make.

 

Actually, unless youre arms and hands are really fat.......it's not difficult to get your hands close enough inside the V to access the synch screws and use a short screwdriver or 1/4"-drive socket, but you might need a glove to protect from the heat and certainly need a flashlight.

Synch must be done EXACTLY as fsm instructs concerning sequence, using left front carb (with idle speed screw) as baseline, then matching that with right front, then balancing both rears the same, then bringing front set in balance with the rears. Pay close attention to any SIGNIFICANT dfifferences between vaccum readings before you start fiddling cuz it's VERY easy to mess things up and wind up no better than when you started and sometimes worse ! Throttle needs to be blipped a couple times after every screw movement to settle in the adjustment.

If you set all the idle mixture screws to 2 1/2 turns, they should require no significant further adjustment.

Once again disregarding "conventional wisdom," possibly a notion from the last ice age, when Triumphs were new, i still don't believe that removing and replacing VFR carbs requires re-synching. After all, what has been done to affect the throttle settings, relative alignments, or the linkages as long as carbs haven't been separated from air plenum ?????? Someone please enlighten me and disabuse me from this perhaps mistaken idea. If IC could draw a picture or someone else could explain, i'd be delighted to learn.

 

So why do you say my carbs need a synch? Is it from watching the vid I posted?

 

Ah....I see

 

I have a bad feeling I'm going to have to remove these carbs again.

 

Doh!!!!!!!!!:doh: