Amal Premier SOOTY AND COLD problem solved

[Tinkerbell]

I agree with the dual throttle. I use the Barnett throttle or the knock-off for about $25. I think the domino has a quicker throttle than the Barnett, it's your choice. I have been making my own cables for years so it's no problem. The 2-into-1 system is a lesson in aggravation and near impossible to adjust with the gas tank in place. you are in Portland Oregon?

Hi Seattle, I am in Vancouver, just across the Columbia from Portland. I work in Portland. I drive a wheelchair van taking sick people to the hospital and kidney clinics. Although the Covid is destroying the economy, it has relieved some of the horrible traffic!

 

[Tinkerbell]

In my case I've tried three carbs two new and one which came off an identical engine running fine. Tried lowering the float
putting in a 106.5 jet. Huge effort at examining the carb bodies making sure nothing is bunged up.
As I say it runs well enough not great but that is a step forward. The problem is I can never get rid of the soot. That means
something is seriously wrong.

Hi Onder,
One thing that I did was to dismount the coils and duct tape them aiming across the bike such that there was no wiring change and the coils fired the opposite cylinder. This definitively proved that ignition was not the issue--in a sense I was lucky that the problem was so immediate--the sooty condition would soot a new plug in thirty seconds after starting --so I really could rule ignition out. My black box is a spark wasting Trispark.

 

[Onder]

One way to get a good rebuilt bike is to have an issue and in frustration start parts changing. When you are done it is usually some small idiotic thing you missed but you end up with a well sorted bike!
Sadly I've ticked all the boxes to no avail. It ain't the coils, the EI, wires, caps nor carbs or anything in the carbs. The valves were removed and checked, they seem fine. Compression is good and very even side to side. The bike can start easily and runs well enough to be used without issue.
BUT the damn plug is black and dry no matter what is changed. The oil gets dirty too quickly.

 

[concours]

Hi Concours,
I went over it with a jeweler's loupe and a flashlight--blew it out with solvent and air . I inspected the hell out of that carb and disassembled it twice , lashed it up on the bike twice and it would soot the plug in thirty seconds. Cold exhaust pipe. Tried it a third time with the old bowl and it worked right away. I too wish there was a definitive answer. My HAL 9000 suggests to put the Premier bowl back on and see if it fails, but I really want to do some riding! This is the first time since getting this beastie that it has really run.
Sincerely,
Kara

Use an aerosol solvent and very GOOD FLOW. Don’t shoot your eye out.

 

[Bernhard]

Hi Concours,
I went over the Premier bowl carefully and tested it on my bench jig for actual fuel level fill. It was fine. One hypothesis is that when that bowl was subjected to uncontrolled violent shaking (i.e. attached to a Norton) it burbled extra fuel. The Premier bowl had the aluminum needle and the old bowl had the brass version . Perhaps the Old Ways are best....

Great that your change has solved the problem, now you need to find another Non Commando and try using that float bowl and confirm if your theory is right or wrong.

 

[Onder]

I too put an old bowel and plastic float with brass/viton valve and there was ZERO difference.

 

[Bernhard]

I too put an old bowel and plastic float with brass/viton valve and there was ZERO difference.

Intresting. Did you have the same problem we have been discussing on this page?
If so, did you trim the gasket on the inside to make sure it was not interfering with the float returning which in turn stops the needle sealing.

 

[Steves]

One way to get a good rebuilt bike is to have an issue and in frustration start parts changing. When you are done it is usually some small idiotic thing you missed but you end up with a well sorted bike!
Sadly I've ticked all the boxes to no avail. It ain't the coils, the EI, wires, caps nor carbs or anything in the carbs. The valves were removed and checked, they seem fine. Compression is good and very even side to side. The bike can start easily and runs well enough to be used without issue.
BUT the damn plug is black and dry no matter what is changed. The oil gets dirty too quickly.

Put a multi meter to your plugs ( not in your list). Either check continuity in ohms or check voltage drop with a battery. Most multimeters have a temp sensor, see if both cylinders are running at the same temp. Maybe revisit the air side of the pilot circuit.

 

[Onder]

New plugs old plugs swapped sides with plugs hotter plugs too. It can be set up so that it runs fairly well fast and slow.
If you put a vacuum gauge on one side will be pulling more than the other and that is when both sides were very carefully
adjusted for cable lift and slide sync.
At idle, the bad side will need more lift (idle screw that lifts the slide) to sync with the vacuum gauges.

 

[olympus]

At idle, the bad side will need more lift (idle screw that lifts the slide) to sync with the vacuum gauges.

This is quite normal...
Are your gauges damped??
If there is any doubt swap over the hoses on the manifolds to compare readings

 

[Onder]

Carbtune is the setup I am using. Yes, I swapped hoses on all four ports.
Ill set up the carbs again strictly by the gauges again tomorrow and report.