Venture Royale carburetor questions

[unwind80]

Thanks for that Goose.

 

I removed the metal plugs hiding the pilot screws and marked their positions with a file. That was the end of the smooth sailing. They are so gummed up that they dont want to move at all. Getting them out won't be a problem, I was able to loosen them. When I try to screw them in to get a setting, however, they don't want to turn in anything past where they were sitting for the last 28 years.

 

I dont want to force it for fear that I break that needle and ruin the carbs. Is there a way to adjust these screws after I clean them without getting a reading first? I might be able to get a reading by backing out the screw instead, but that would be pretty tricky.

 

On my other bike I have adjusted these hidden screws after assembly by setting them so the carbs will pull maximum vacuum as part of the carb sync process. Does that work? I should say that my other bike doesn't run all that well either

 

**Update:** I was able to get a reading on one of the carbs. One of the screws is moving with the problem that I described above. The other two are frozen solid. I managed to mess one of those up pretty bad too. I'm getting a little frustrated at this point. Anyone have a set of carburetors for sale? There is a set on ebay for 86-91 models. Can I get that to work with my 83?

Edited June 8, 2011 by unwind80

[twigg]

A carb soak won't do the trick. You need to completely disassemble and spray cleaner and compressed air through every passage. The emulsion tubes need to be removed and cleaned and make sure that every orifice is open.

 

The rubber plugs for the jet block are still available, I just had to replace a set of them.

 

The pilot screws need to be gently turned in, counting how many turns and fractions of turns, until they bottom. Then they need to be removed, the spring washer and o-ring under them need to come out, and those passages need to be blown with spray carb cleaner and compressed air. Upon reassembly you lightly seat the pilot screws and back them out to the count you made previously.

 

A carb soak is a very bad idea because it ruins rubber. There are rubber seals on the butterfly shafts that are not supposed to be removable. If they get damaged you are in a world of hurt.

 

The butterfly shaft seals are easily replaceable. Single-lipped seals are available for $5.50 a pair from MikesXS.com, and double lipped from motorcyclecarbs.com at $6 each.

[MiCarl]

Thanks for that Goose.

 

I removed the metal plugs hiding the pilot screws and marked their positions with a file. That was the end of the smooth sailing. They are so gummed up that they dont want to move at all. Getting them out won't be a problem, I was able to loosen them. When I try to screw them in to get a setting, however, they don't want to turn in anything past where they were sitting for the last 28 years.

 

I dont want to force it for fear that I break that needle and ruin the carbs. Is there a way to adjust these screws after I clean them without getting a reading first? I might be able to get a reading by backing out the screw instead, but that would be pretty tricky.

 

On my other bike I have adjusted these hidden screws after assembly by setting them so the carbs will pull maximum vacuum as part of the carb sync process. Does that work? I should say that my other bike doesn't run all that well either

 

**Update:** I was able to get a reading on one of the carbs. One of the screws is moving with the problem that I described above. The other two are frozen solid. I managed to mess one of those up pretty bad too. I'm getting a little frustrated at this point. Anyone have a set of carburetors for sale? There is a set on ebay for 86-91 models. Can I get that to work with my 83?

 

If they won't screw in just remove them. The point of counting them in first is to get them right back to stock so you'd hopefully start closer to a good mixture. When you reassemble just put them at 2 1/2 turns and tune from there.

 

If you've got some stuck now you might try heat again. Since there are springs and o-rings under there I'd suggest gently boiling them (maybe in lemon juice) rather than a torch.

 

In theory using vacuum to set the mixtures should work. In practice you probably cannot read the gauges well enough for the really fine tweaks that make it run well.

[unwind80]

Boiling sounds like a good idea. I was worried about the torch and that o-ring also. I need to cool down a bit and try again tomorrow I think. I'm feeling a little torched myself. Its hot in Phoenix this time of year

[unwind80]

I decided to take everyone's advice and replace the rubber plugs. It took a couple weeks to get these in the mail along with the new jet.

 

Everything is back together now, and she runs It won't idle well below about 1500 RPM, but I am hoping that the carb sync may solve that problem. I will be able to get that job done in a couple days.

 

I'll keep you all posted.

[twigg]

A carb soak won't do the trick. You need to completely disassemble and spray cleaner and compressed air through every passage. The emulsion tubes need to be removed and cleaned and make sure that every orifice is open.

 

The rubber plugs for the jet block are still available, I just had to replace a set of them.

 

The pilot screws need to be gently turned in, counting how many turns and fractions of turns, until they bottom. Then they need to be removed, the spring washer and o-ring under them need to come out, and those passages need to be blown with spray carb cleaner and compressed air. Upon reassembly you lightly seat the pilot screws and back them out to the count you made previously.

 

A carb soak is a very bad idea because it ruins rubber. There are rubber seals on the butterfly shafts that are not supposed to be removable. If they get damaged you are in a world of hurt.

 

Just a quick word about this in what is an excesllent post:

 

The butterfly shaft seals are delicate. By now, the originals are over twenty years old, and they have gone from "soft and sealing" to "hard and not at all air-tight".

 

Replcements are easy to come by, and replacing them is very straightforward.

 

mikesxs.com has them for around $5.50 a pair, and motorcyclecarbs.com has them at $5 or $6 each.

 

The mikesxs are the single-lipped which work just fine. The originals are double-lipped and are the $6 each version.

 

There are a few things to note.

 

The butterfly valve screws are brass and "staked". With a good fitting screwdriver and a light touch with a small hammer they come out very easily. They are M4 thread, and Lowes carries replacements.

 

When you reassemble them use BLUE locktite on the threads, and all will be well.

 

These seals are overlooked because Yamaha never offered those parts, they were always part of an expensive carb body sub-assembly. But they should be replaced, and the job is easier to do than it is to describe.