Moving pilot air screw to left side on Monobloc carbs.

texasSlick

texasSlick

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Has anyone tried, or is it possible, to move the pilot air screw to the left side of a Monobloc carburetor? Seems like it might be possible to drill and tap the left side, and plug the right side.

I am thinking to solve the problem of the chopped carb blocking access to the pilot air adjustment.

Slick
 
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No idea, but man, that'd be nice...

Honestly, though, there's a long, thin screwdriver my friend has that makes the pilot screw less a bane of my existence than the throttle stop screw, which is impossible for me to see/access/turn with reliability and accuracy. Hard to get a screwdriver in there, hard to turn with fingers...ugh.
 
It occurs to me that an extended throttle stop screw on the LH carb would make things much easier, but I can only find one for the Concentrics. Before I get stupid with JB weld, does anyone know if such a thing exists?

(Or a machinist willing to turn some for a few of us at a decent price? :D )
 
texasSlick said:
Has anyone tried, or is it possible, to move the pilot air screw to the left side of a Monobloc carburetor? Seems like it might be possible to drill and tap the left side, and plug the right side.

I am thinking to solve the problem of the chopped carb blocking access to the pilot air adjustment.

Slick
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Shame this is a problem for just an infinitesimal number of lunatics, myself among them. Otherwise you could patent a solution and retire [again]. On a more serious note, it would be cool if you could figure out a simple way to do this. Meanwhile as AgentX notes a long thin screwdriver is the best solution I have been able to come up with.
 
As for the throttle stop screw:

I shaped fuel tubing into a 45 degree arc with heat. Then rotated the banjos connecting the two carbs to meet the arc, giving me a clear access to the throttle stop screw. I still have to feel around for it, but I plan to make a small screw driver with a rubber nose that will grab and hold fast the throttle stop screw.

Here's hoping someone will chime in with a solution to the pilot air screw problem.
 
texasSlick said:
As for the throttle stop screw:

I shaped fuel tubing into a 45 degree arc with heat. Then rotated the banjos connecting the two carbs to meet the arc, giving me a clear access to the throttle stop screw. I still have to feel around for it, but I plan to make a small screw driver with a rubber nose that will grab and hold fast the throttle stop screw.

Here's hoping someone will chime in with a solution to the pilot air screw problem.
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The rear facing fuel hose loop for the connector hose between the 2 carbs was recommended in the UK motorcycle mags way back when. I found though that it doesnt allow clearance for the standard air filter if that's a concern.
 
Good idea. I'll try that; I was going to re-plumb the fuel arrangement anyway.

Thanks--I have Uni sock-style filters on the carbs, which I think are better than the stock element anyhow.
 
Bodger said:
The rear facing fuel hose loop for the connector hose between the 2 carbs was recommended in the UK motorcycle mags way back when. I found though that it doesnt allow clearance for the standard air filter if that's a concern.
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As shucks, Bodger, you just popped my bubble! I thought I had come up with a new mod that would make me world famous!

Well, perhaps not, but the 45 degree arc does not take up very much room, and the stock air filter might be accomodated, should anyone want the stock setup. The stock filter was very good at filtering big leaves, which is why I run velocity stacks.

Slick

@AgentX: It should be easy to drill and tap the head of the throttle stop screw, and extend it with an 8-32 screw. Then with a jam nut at the head end of said screw, adjustment should be finger easy. Put away the JB Weld. Might do this myself.
 
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Yeah, was thinking similar. Was just going to lock the threads together with the JB weld instead of using a jam nut...

Edit: Oh, head end...I get that. I'd JB weld that one in place too lol

Edit 2: McMaster has lots of thumb screw options which would be perfect for this.
 
My latest thoughts on this is to get a 2 inch long piece of vacuum tubing that can be persuaded over the throttle stop screw head, then rotated from below.

Same idea for the pilot air screw, but a longer piece of tubing.

Remove both tubes when carbs are dialed in, put them in tool box, and in a year or two, wonder what they were used for.

Slick
 
I followed AgentX's lead, and modified my left side throttle stop screw. Have not tried it yet as carbs are off for sleeving.

Moving pilot air screw to left side on Monobloc carbs.

6-32 thumb screw, no jam nut needed with a drop of red Locktite.

Slick
 
Nice!

I am back at my parts-horde in the shed (inherited from bike's original owner) and was hoping to find a spare throttle stop screw, but no luck. I'll have to try on the one currently in the carb.
 
I once had a set of right and left Monoblocks that I used on a modified flat track head that had flanges welded to a single carb head on an A65 BSA. The carbs were situated similar to that of a stock Norton head.

Moving pilot air screw to left side on Monobloc carbs.
 
Just received the tool. It does not fit, haha. Regardless a fun piece to have in the box. Its nice for the throttle stops tho. It is about the size of a quarter.
 
seanalex said:
Just received the tool. It does not fit, haha. Regardless a fun piece to have in the box. Its nice for the throttle stops tho. It is about the size of a quarter.
Click to expand...

You will find many uses for it as time passes. I could have used it today trying to remove the plug (slotted screw) from an electrical box mounted too close to the ground to get a 6 inch long screw driver in it.

Slick
 
texasSlick said:
Has anyone tried, or is it possible, to move the pilot air screw to the left side of a Monobloc carburetor? Seems like it might be possible to drill and tap the left side, and plug the right side.

I am thinking to solve the problem of the chopped carb blocking access to the pilot air adjustment.

Slick
Click to expand...
i went to a single carby because of that problem and tuning, even with vac gauges attached i couldnt get to the adjustments on the two carbys
 
Dan1950 said:
I once had a set of right and left Monoblocks that I used on a modified flat track head that had flanges welded to a single carb head on an A65 BSA. The carbs were situated similar to that of a stock Norton head.

View attachment 97974
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lol tha tslooks what was on my Atlas, now i just run the left one on 2 into 1 manifold ,definitely not original 1965 Atlas carbys
 
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