Anyone maybe figure this out

[chiz]

I made a new topic because this is soo bizarre..

  None of the other carbs are effected like this only #1
  When I start the bike I get a poor idle because #1 is not working
  When I block the air bleed jet (the removable one) at the carb mouth the idle picks up and #1 begins to work.?
  BUT when I block the vacuum hose that normally goes to the gas valve which is connected to#1 as well while the air bleed jet is still blocked the idle drops and #1 stops working.??
  When I open the vacuum hose cyl#1 resumes working unblock air bleed back to not working???
  With the air bleed blocked and the vacuum hose open and #1 working the mixture screw actually works and has an effect on engine idle like it should.
  The mixture screw has NO effect if air bleed jet is not blocked or vacuum hose or both.

I know this might be difficult to work out if the bike is in front of you if I do any of the above to the other three carbs it has a detrimental effect in fact the opposite of what happens to #1 carb. 

  Said another way   If I block the air bleed jet of #1 and allow the vacuum hose to suck air #1 appears to preform like the rest of the carbs.

  Any theories much appreciated.
                                                    Chiz

[pict]

I presume you are using an auxiliary tank or you are applying vacuum to the petcock by some other means to keep the fuel flowing. In any case the vacuum tube from the petcock to the No1 inlet needs to be blocked for normal operation... either by being connected to the petcock, or plugged up if using an auxiliary tank. You say that the carb works normally if the vacuum tube is plugged and the air jet is unplugged. This is how it should be is it not?

Edit - sorry I don't think you said that. Let me mull over the combinations again.

When you start the bike and get poor idle cause of No1 carb is the vacuum tube plugged (or connected to the petcock)? I had a similar issue using an auxiliary tank and had forgotton to plug the vacuum tube so it wasn't sucking air on the far side of the carb.

[Flynt]

I made a new topic because this is soo bizarre..

 None of the other carbs are effected like this only #1
 When I start the bike I get a poor idle because #1 is not working
 When I block the air bleed jet (the removable one) at the carb mouth the idle picks up and #1 begins to work.?
 BUT when I block the vacuum hose that normally goes to the gas valve which is connected to#1 as well while the air bleed jet is still blocked the idle drops and #1 stops working.??
 When I open the vacuum hose cyl#1 resumes working unblock air bleed back to not working???
 With the air bleed blocked and the vacuum hose open and #1 working the mixture screw actually works and has an effect on engine idle like it should.
 The mixture screw has NO effect if air bleed jet is not blocked or vacuum hose or both.

I know this might be difficult to work out if the bike is in front of you if I do any of the above to the other three carbs it has a detrimental effect in fact the opposite of what happens to #1 carb.  

 Said another way   If I block the air bleed jet of #1 and allow the vacuum hose to suck air #1 appears to preform like the rest of the carbs.

 Any theories much appreciated.
                                                   Chiz

My guess...  the vacuum hose of #1 is leaking air and making the fuel mixture lean.  When you block the air jet, you change the air mix such that the leak and the fuel that's coming in somehow reach a flammable mixture.  This is another rabbit hole...

Send carbs to be properly cleaned and tuned...  adjust your valves (or maybe not...  they're probably fine or at least close enough given your hack is making it run)...  then reassemble and see what you have.  Until then, make sure your vacuum hose isn't sucking air...  time for a suck test.

Frank

[chiz]

i am using a separate tank the vacuum hose that would normally go to tank is just left hanging... when I block air bleed jet and close vacuum line cyl wont work but if I open vacuum line with air jet still blocked cyl works....mind boggling

[chiz]

OK stop the panic all my fault sorry to waste everyones time. I pulled the carb bank off and because I realised I had not synced the carbs when I had them off yesterday and thought the#1 may be shut tight at the butterfly... So  did a down and dirty carb sync looking at the tiny hole just covered by the base carb butterfly and brought the rest of them to the same spot via the sync screws also set the mixture screws just flush with the carb throat. Did not even hook up the throttle cables or choke just turned up the idle screw and got it to start on manually pushing the choke rod by hand. Once it started and I remembered to close the vacuum line that goes to tank viola the damn thing started to work and now when I blocked the air jet it stumbled like it should not only that the mixture screw actually had an effect on the bad carb as well my bad lesson learned. Chiz

[copper]

K.I.S.S.