VF700F Carb cleaning

Mophead

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OK all you Honda Carb experts. Have a 1985 VF700F Interceptor and have carbs off for ultrasonic cleaning. Have everything taken apart, all jets removed, slides and spring out. I have not taken the idle screw valve out.

On this bike the manual says there is a plug that has to be removed to get to the idle screw. There were no plugs in these carbs and idle screw is clearly visible. Should I take the idle apparatus out before dunking in the cleaner or just leave them in? Getting those reset correctly after reinstalling the carbs could be tricky.

Someone has been into these carbs previously hence the missing plugs on the idle screw. Also, some rounded phillips screw heads on the float bowl covers. I have replacement screws for the float bowls. Sometimes it pays to rathole those 35 year old parts. Also have many jets left over and many are brand new. The connecting fuel rail lines seem to be in good shape (will replace the orings). Removing those fuel rail lines showed some older broken off ends still in the carbs but inspecting the lines the ends of them are all intact. After seeing this I wondered how the bike even ran at all. Now the old broken pieces are cleaned out and perhaps we can get a seal on those lines.

The last time I did carbs was about 35 years ago on a V65 Sabre. Had to do those three times before getting them right but was trying to shortcut a barn find and get it running. Had about 6000 miles on the bike and I sold it to a friend with 85,000 miles on it. I cleaned those with Berryman's carb cleaner with basket. That got them clean.

Anyway, collective wisdom from some of you who are old enough to have gone down this road. Take the idle crew valving and components out before dipping or leave them in?

My hesitation is from there being several springs, washers, etc on that idle screw assembly. Sourcing parts for this old stuff can be difficult so if it doesn't need to come out but going to all this work to have clean carbs it would probably wise to remove and inspect the idle screw stuff.

Have I answered my own question? When I get these back on and they don't work I want someone to blame like Uncle Phil or Sadlsor.

Oh, and what kind of witches brew do you use in your ultrasonic cleaner for carbs? I see all kinds of solutions water and simple green, and Pinesol, white vinegar, speciality powders to mix in (probably repackaged baking soda)
 
With all the times I pulled out the V45/VF700 & V65 Sabre carbs, I was only really successful one time!

My '85 V45 Sabre (Canadian) ran horrible the whole 30K miles I rode it. And the one time I actually rebuilt carbs successfully was the very last time I did the V65 Sabre carbs. I say successfully was because they actually worked like they were supposed to.

I avoided tearing into the 96 ST1100 carbs, I didn't even want to try!

I wished I could give you some pointers, but I can't, other then make sure you have replacement parts for whatever you pull out/apart. :unsure-2x:
 
I would definitely remove the pilot screws, but before you remove them, screw them in and count the turns so you can put them back the same way. The pilot circuit ports are pretty small and easily clogged so these and the low speed jets are probably the main source of any blockages in gummed up carbs. I'd be surprised if you were unable to get pattern replacement parts e.g. from Keyster or Wemoto if the OEMs are NLA.

I believe the EPA mandated the use of plugs over the pilot screws so that these would not be tampered with to correct lean but EPA-friendly operations.
 
Yes remove them, make sure you get the o-ring and washer out when the screw is out.
I bent the tip of a safety pin to make a hook to fish them out.
 
The slow speed jets appear to be blocked. When I take my Forney tip cleaner I cannot run it all the way through the jet on all four carbs from either end. I can go sideways through the smaller holes on the bottom of the jet but not all the way through the main body of the jet. Is there a stop inside the jet or should it go all the way through the main body of the jet?
 
If they have not been apart before I would recommend going 1 size up on the primary jets also, I have seen a couple of dyno runs on older bikes and they all seem to run a bit lean because of the newer fuel mixture
 
Also there are some really good books that describe carburation systems, They all are based on the mixture of fuel and air, it is how it is done that changes. But it has the same goal. If you are up on the theory the rest can sometimes be easier to understand and identify the circuits in the carb. Helps in all 4 stroker motors too.
 
The slow speed jets appear to be blocked. When I take my Forney tip cleaner I cannot run it all the way through the jet on all four carbs from either end. I can go sideways through the smaller holes on the bottom of the jet but not all the way through the main body of the jet. Is there a stop inside the jet or should it go all the way through the main body of the jet?
The low speed jets should be open from base to tip but they do neck down smaller part way through; I used a strand pulled from a wire brush to push through (have cleaned both ST1100 and 86 VFR750 carbs recently); I have also heard of folks using guitar strings for this job. Again it may be easier just to buy new jets.
 
The low speed jets should be open from base to tip but they do neck down smaller part way through; I used a strand pulled from a wire brush to push through (have cleaned both ST1100 and 86 VFR750 carbs recently); I have also heard of folks using guitar strings for this job. Again it may be easier just to buy new jets.
I have one soaking in brake cleaner so will try to clean it and see what happens. These carbs are a real mess. Took the idle screws out. Number one had the wrong spring and no washer. Number two had washer but no oring. Number three and four had all the parts there but orings were tough to remove. Got the heat gun out and heated up the carb body and down into the hole to loosen them up and they came out.

This is gonna be fun.
 
I can sympathise. The 1990 ST1100 that I bought in 2016 (as a known, non-runner) had been parked up for 10 years with no thought to carb or tank draining. I got REALLY good at pulling the carbs off and remounting. That one had not been messed with before I bought it so all of it was standard, just really dirty.
 
My 85 XL600 thumper with the duel sequential carbs looked like this after cleaning them and letting ethanol fuel sit in the bowls for not more than about four weeks; I should have taken pics before the first cleaning. I'm not sure what metal was used, I think it's almost a pot metal, but man did that refoul quick. For me, moral of the story was simple; drain the bowls.


838.JPG



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I have one soaking in brake cleaner so will try to clean it and see what happens. These carbs are a real mess. Took the idle screws out. Number one had the wrong spring and no washer. Number two had washer but no oring. Number three and four had all the parts there but orings were tough to remove. Got the heat gun out and heated up the carb body and down into the hole to loosen them up and they came out.

This is gonna be fun.
Having worked on CB500/4 and CX500 carbs I can relate...
I use designated carburetor cleaner spray, which really softens/removes accumulated crud... and remembers the cut on your fingers...
(brake cleaner does pretty much nothing; even acetone works better...)
Compressed air to free orifices (got me a small blow gun with rubber tip that seals around the opening)...
Nylon bristles to poke... (metal might unintentionally widen the bore, even leave scratches)
Ultrasonic cleaner (distilled water with 5% detergent rated for carburetor cleaning)...
If required start from above...

Upon replacing jets, etc... I opt for OEM if possible, quality of Honda brass is unbeaten...
Or at least Keyster kits which come pretty close... as long as you receive the correct one (had to order the CX500 sets twice to get parts that actually fitted...)

OEM w/shop manual and parts catalogue help... a lot... like for the initial settings to even get that thing started after the rebuild...
This would be my first source for locating part numbers and part descriptions:


And BTW, this is how those 70ies carbs looked like...

IMG_0480.JPG IMG_0483.JPG IMG_0504.JPG

got it running though :cool:
 
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I've sourced parts and info from this site. v4dreams.com

This guy really loves his early v4 bikes and has a lot of info on Carbs and other areas of the bike as well. Check it out. I think you will find everything you need there and you may just want to replace those low speed jets. I've had to use Micro drill bits to clean slow jets, I think Harbor Freight sells a cheap set of the bits. However, the V4 site link above has some jet options if you want to go a size up. Good luck with the cleaning they can be tricky, but worth it.
 
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