Substandard parts.

[Janacek]

I am most grateful for the replies.
The new ratchet pinion and quadrant came from the same supplier,but on examination,the quadrant is for the pointy teeth pinion,and the pinion they sent is the old type squared teeth.
Got a new pinion with pointy teeth and fitted it today and seems ok,no jamming.
Just got to fix the Victor Sylvester tickover and the bike will be almost perfect,(for a 1957 B31)Those of you of a certain vintage will remember Come Dancing years before Strictly,and Sylvester used to call out the dance steps,"Slow,Slow,Quick Quick Slow" except my bike it's, Slow,Slow,ignition retarded,then Quick,Quick Slow and stop ignition advanced.
Having exhausted all other possible causes,air leaks,jetting,ignition etc,I now suspect the carb fuel level is too high.When you turn the fuel off with the engine running,it speeds up a little just before it stops caused by the fuel level in the float chamber dropping.
I think too high a fuel level could be the cause of this slowing and stopping,as blipping the throttle it will tick over nicely for a few seconds and then gets a bit too much fuel.
Another clue is it starts easily with the fuel on, but is most reluctant to start when I flood the carb from cold.
The carb fitted has a machined float needle seating so I will experiment with different thickness washers.

[limeyrob]

Assuming its a monobloc, then if its original / old there should be no washer under the valve, if its a new replacement they have washers.  So if its old and has a washer try just removing it.
The dimple on the cover is the level, you can check it by taking the nut off the pilot jet and putting some silicone tube on as a manometer.  I've been doing all this the past week on a Matchless and been surprised by how much difference getting the float level right makes.  Its worth the effort.
If its got a brass valve you can put solder on the end then file it down to adjust.

[Janacek]

Assuming its a monobloc, then if its original / old there should be no washer under the valve, if its a new replacement they have washers.  So if its old and has a washer try just removing it.
The dimple on the cover is the level, you can check it by taking the nut off the pilot jet and putting some silicone tube on as a manometer.  I've been doing all this the past week on a Matchless and been surprised by how much difference getting the float level right makes.  Its worth the effort.
If its got a brass valve you can put solder on the end then file it down to adjust.
[/qu
The carb is a replacement monobloc with a machined face for the float needle valve.Replaced the fibre washer with a thinner copper washer and the tickover on advance is much more reliable,(not perfect) but much better.
Thanks, Terry.

[cdsdorset]

Assuming its a monobloc, then if its original / old there should be no washer under the valve, if its a new replacement they have washers.  So if its old and has a washer try just removing it.
The dimple on the cover is the level, you can check it by taking the nut off the pilot jet and putting some silicone tube on as a manometer.  I've been doing all this the past week on a Matchless and been surprised by how much difference getting the float level right makes.  Its worth the effort.
If its got a brass valve you can put solder on the end then file it down to adjust.
[/qu
The carb is a replacement monobloc with a machined face for the float needle valve.Replaced the fibre washer with a thinner copper washer and the tickover on advance is much more reliable,(not perfect) but much better.
Thanks, Terry.

Amal actually supply a set of various thickness washers to get the float height correct.

[Janacek]

Assuming its a monobloc, then if its original / old there should be no washer under the valve, if its a new replacement they have washers.  So if its old and has a washer try just removing it.
The dimple on the cover is the level, you can check it by taking the nut off the pilot jet and putting some silicone tube on as a manometer.  I've been doing all this the past week on a Matchless and been surprised by how much difference getting the float level right makes.  Its worth the effort.
If its got a brass valve you can put solder on the end then file it down to adjust.

.   

Checked the fuel level with a plastic pipe from the pilot jet and it seemed to be level with the dot on the float chamber cover.Looking at the plug,it's chocolate brown so running a bit rich.Rather than get different size shims for the float needle valve,I attacked the copper washer with grinding paste on a steel plate and measured the distance the float moved with and without the washer.It was 10mm with and 5mm without.Ground the washer to go in between and settled on 7-8mm.Tickover on full advance is now very reliable and the plug is now mid brown.Didn't realise that a tiny movement of the float would alter the overall mixture.Just one tiny thing,when changing gear the engine frequently misses a beat before picking up again which means,er something,but I can live with that.Just the poor brakes to sort out now.There will always be something that needs attention.But it keeps me out of the pub and away from women of dubious character!