Amal Premier SOOTY AND COLD problem solved

Hi All and Onder,
I took one last stab at the RH new Premiere on my MKIII . I put an old bowl with the old style float on it and did standard 1-1/2 mixture and equal throttle stop settings. Fired it up and I have an even performance and warm exhaust and decent looking plug. I do not believe that the carb is
fundamentally going to be a problem . I did do a fuel level check on the Premier bowl and float and it was within spec. So I do not have a smoking gun here , regarding what might have been the trouble . The only other change was to minimize overall lash between the splitter and the two individual cables. I think some real work could be done, perhaps with a new splitter and two new sub cables. I suspect this could be a source of headache if those pieces do not restore to exactly the same place every time.

In the past 18 mos , I have personally rebuilt the gearbox, installed a Trispark, installed Wassell EVOs, removed Wassels , replaced pistons, taken barrels to +.020, renewal of cylinder head , installed Premier carbies. Battled with Premier carbies. And after all this , this morning is the first time I think its all running OK at a basic level.
Thank you everyone! I would never have gotten this far without you@!
Kara

Good news!! Ride it and enjoy it... It's why we buy them

We need to get a vacuum gauge on that bike to make sure your carbs are actually syncing.

This will resolve any cable issues.

I use a twin cable twist grip.

There is more than one journey with a Norton. The first is getting it to the road.

Great to hear you've sorted it.

I can thoroughly recommend the Madass140 single cable gantry, as I think others will too.



Cheers,

cliffa.

The more parts you have in an assembly, the more that can go wrong.

hallelooya jubilee

swooshdave said:

We need to get a vacuum gauge on that bike to make sure your carbs are actually syncing.

This will resolve any cable issues.

Madass140 Single Throttle Cable Amal Kit

im not sure how many of you have bought these but I just installed it last night and it’s beautiful. I can’t tune it yet but I can’t wait to fiddle with it. Despite the instructions being succinct even I managed to get them on just fine. I do have the stop nuts on the cable wrong in the...

www.accessnorton.com

Click to expand...

Hi Dave,
I would love to learn more about tuning. I could not really take the next step until the basics were in place, which I believe they are at this point. I don't know that I would want to eliminate my chokes--it seems to like a little choke when starting from cold. Maybe the dual cable throttle makes sense. I am so relieved to get it sorted, I may not do much but enjoy it this summer and leave tinkering until the endless gray despair of Portland winter.
Love,
Kara

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?

It is a bit pedantic but actually you didn't solve the problem. You cured it by replacing parts but we still don't actually know what was wrong.

Ongoing rare but persistent random issues with Premier carbs are a concern. Very frustrating in fact.

My new Premiers run very well when the engine is warm.

But it is very difficult to warm up and a long list of changes including chokes, pilot Jets, slides, needle changes, float heights, repeated cleaning out of internal passages and tuning by two different mechanics has made no difference so far.

Well I guess I am on that bus too. One piece of advise was to make sure the cables were operating together, slides in sync etc.
My throttle is a two wire each one adjusted independently. If they both pick up from zero at the same time one side is slighly late
to arrive at the top compared to the other. If they are set at the top together then one side lifts slightly sooner than the other.
Using a vacuum gauge I can set the two carbs to pull even at idle but they are not even mechanically.
At this point the bike runs reasonably well, starts within three kicks every time usually the first one, it will idle and run at small throttle both in town and out on the road.
Problem is still the plug is black with dry soot. Always. I have tried everything and it just never goes away , different carbs, jets
settings etc. I have been told that the exhaust valve is sticking. Have another head next rainy day I tempted to pull it just
because I've run out parts changing to do!
I cannot believe it is a carb issue but I am right and truly puzzled.

johnm said:

It is a bit pedantic but actually you didn't solve the problem. You cured it by replacing parts but we still don't actually know what was wrong.

Ongoing rare but persistent random issues with Premier carbs are a concern. Very frustrating in fact.

My new Premiers run very well when the engine is warm.

But it is very difficult to warm up and a long list of changes including chokes, pilot Jets, slides, needle changes, float heights, repeated cleaning out of internal passages and tuning by two different mechanics has made no difference so far.

Click to expand...

Hi John,
You are absolutely correct that I did not truly solve the problem, but I finally have gotten the bike to square one. I bought it as an unknown 18 months ago and it has never run correctly before--I did not really know that it could run correctly. It was a big bag of variables. And I am new to Norton mechanicing. Now at least I have the experience of Amals that set up equally, have decent plugs and run well. This feels like progress.
Sincerely,
Kara

Onder said:

Well I guess I am on that bus too. One piece of advise was to make sure the cables were operating together, slides in sync etc.
My throttle is a two wire each one adjusted independently. If they both pick up from zero at the same time one side is slighly late
to arrive at the top compared to the other. If they are set at the top together then one side lifts slightly sooner than the other.
Using a vacuum gauge I can set the two carbs to pull even at idle but they are not even mechanically.
At this point the bike runs reasonably well, starts within three kicks every time usually the first one, it will idle and run at small throttle both in town and out on the road.
Problem is still the plug is black with dry soot. Always. I have tried everything and it just never goes away , different carbs, jets
settings etc. I have been told that the exhaust valve is sticking. Have another head next rainy day I tempted to pull it just
because I've run out parts changing to do!
I cannot believe it is a carb issue but I am right and truly puzzled.

Click to expand...

Hi Onder,
I did two things that changed this condition completely--tried a different bowl with the old style float with brass needle. This bowl was tested on my fuel fill jig so I had confidence it filled within spec. I also minimized free play in the individual throttle cables because they were not settling to the same point every time. And now both carbs adjusted almost identically in terms of idle aperture and mixture setting. I am just learning all of this for the first time. Since I am a novice --if I think a part is the issue I replace it. I would hope as I get better at diagnosis, there would be a smaller pile of perfectly good scrap!

Regarding carb settings, I used a .750" dia. delrin ball on the end of a long screw to set throttle opening for cable sync. My sense is that I don't care about the top of the carb. The air flow is a function of the height of the slide above the bottom of the carburetor bore. A slip fit on the ball says you are opening equally when the cables are being used. I used a .201" drill bit to set a reference mark on the throttle stop screw such that each side is a slip fit on the .201" bit , relative to the bottom of the carb bore. This reference mark is within 1/2 turn of the actual throttle stop idle setting and is easier to keep track of. Actually a .232" bit is probably even closer on my bike. My theory is that if the motor is OK and the carbs are very close in their manufacture ( brand new!) and are functioning correctly ( prayer appropriate here) , those adjustments must be fairly close --otherwise you are compensating for some other issue. I am actually thinking of making a couple of more delrin feeler balls at 1/4 and 1/2 inches to see how consistent the cable pull is at different apertures .
Kara

Tinkerbell said:

Hi John,
You are absolutely correct that I did not truly solve the problem, but I finally have gotten the bike to square one. I bought it as an unknown 18 months ago and it has never run correctly before--I did not really know that it could run correctly. It was a big bag of variables. And I am new to Norton mechanicing. Now at least I have the experience of Amals that set up equally, have decent plugs and run well. This feels like progress.
Sincerely,
Kara

Click to expand...

I agree it is great you have sorted your problem.
Pleased you have made progress.

My frustration is that these issues keep showing up on new carbs.

So, did you closely examine the float bowl assembly that was not functioning correctly?

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.

concours said:

So, did you closely examine the float bowl assembly that was not functioning correctly?

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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....

I had similar symptoms with bowl/fuel heights that were too high.

You may also want to examine the bowl gasket. I have had floats intermittently hang up on them fixed by trimming the inside of the gasket to allow more room.

Tinkerbell said:

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....

Click to expand...

I understand your hypothesis, but it suggests the DESIGN is NFG, and clearly there are thousands of them working just fine.
That experiment self solved.

I was roundaboutly attempting to suggest that besides float level, there can be other troubles. Did you check these passages are completely open?

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