Amal Premier ( brand new) issue SOOTY and Cold!

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Hi Everybody,
I got my new 932 Premieres on the MKIII. Left carb great at normal settings--nice idle , nice plug . Careful sync and setup . Right carb won't heat up the exh pipe, instant sooty plug , feels like its running on one cylinder. Disassembled carb , blew out all passages including the two teensy ones with solvent and air-- double checked float and other bits. Same problem at any reasonable settings. Reversed ignition system (coil/ HT) . No dice. Revived one of my old 932s. Basic settings, put on bike. Warm pipe like left side, good looking plug, decent running. No fight needed. At this point I don't see what I can do to further troubleshoot the right side Premiere ---and its off the bike until I can figure something out. I seem to be collecting a stack of unusuable carburetors ( 2-Wassell, 1-Premiere.)
Thanks to everyone for your endless patience ----Kara
 
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Hi Everybody,
I got my new 932 Premieres on the MKIII. Left carb great at normal settings--nice idle , nice plug . Careful sync and setup . Right carb won't heat up the exh pipe, instant sooty plug , feels like its running on one cylinder. Disassembled carb , blew out all passages including the two teensy ones with solvent and air-- double checked float and other bits. Same problem at any reasonable settings. Reversed ignition system (coil/ HT) . No dice. Revived one of my old 932s. Basic settings, put on bike. Warm pipe like left side, good looking plug, decent running. No fight needed. At this point I don't see what I can do to further troubleshoot the right side Premiere ---and its off the bike until I can figure something out.
Thanks to everyone for your endless patience ----Kara
As it's new maybe there's a manufacturing fault with it Kara, pehaps a drilling not clear or similar?
 
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As it's new maybe there's a manufacturing fault with it Kara, pehaps a drilling not clear or similar?
Hi Dave,
As far as I can tell I have checked all the internal passages with air and solvent and checked the #19 pilot for swarf.
 
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I guess I have to go find my ancient clapped out carbs.....
I had to do whatever it took to get to some kind of "square one" to begin to sort it out. I would have liked the new pair of carbs to drop on the bike and be magnificent , but I seem to have to buy everything twice and then fight with it. And I am a good technician but I am new to motorcycles. So I don't have 40 years of experience--I have been depending on the strategy of new parts giving me a good starting point, but it has not really worked that way. The pair of Wassel EVOs are scrap and potentially one Premiere may have to join the pile.
Sincerely,
Kara
 
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What a conundrum, what is the end of the exhaust like, dry soot or oily? Does it blow unburnt fuel out the back? First thought was float level or float valve, but you checked. Can you swap those items over?
It’s not going to help but I had a similar problem, rebuilt the cylinder head, new rings and honed the barrel. Sorted the problem!
Does this just happen at idle or right through the carb operating range? If just at idle then idle circuit, if right through all throttle openings then it sort of implicates the float bowl area as idle circuit and needle jet affected.
 

lazyeye6

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Easy things first: Try ANOTHER new spark plug, swap the plug leads, swap the coils.
I found a sizable chunk of swarf in the mixing chamber of my new Premiere and had to pick it out as it wouldn't blow out with air.
 
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Too rich to run? Is the air slide up out of the way?

It’s fairly common for the float to snag on the gasket, holding the needle valve open, but that usually makes petrol run out of the carb.
 

gtiller

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Some good advice already - remember that carb issues are ALWAYS electrical and vice versa!

So if you have electronic ignition you can safely start swapping stuff from left to right.
Spark Plug
Leads and Caps
Coils

Do them separately, rather than all at once so you can track down what the issue is easier.

I would be inclined not to bring more new parts into the mix, as you are just introducing new unknowns.
Your left cylinder is good, so rob parts from that until it breaks.


If, after all that your cold cylinder stays on the right side, then turn your attention back to the carb.

Next thing to check would be does the cylinder fire when you open up the throttle on a ride, or is it just when your ticking over on the pilot circuit.
When you tickle the carbs before start, is it taking about the same time on both sides to get a wet finger?
Then it's on to looking at thing like fuel height in the float bowl.
 
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I went through everything you have wasting hours and hours on a new pair of premiers. The problem was only in the idle area, I solved almost all of it except it was still a little irregular at idle and when feeling the exhaust the left side would give a strong bap..bap..bap. The right side was a pitiful puff..puff..puff and nothing would change that. Any other throttle position and it ran very well. To finally rule out all other possibilities I installed a single 34mm Mikuni and both sides ran identically. I left the Mikuni in place so the owner could try it out. He was very happy but still wanted the dual Amals. I handed them to him in a box and wrote off about 20 hours of intense frustration, dead ends and wasted time. I told him I would work on any part of his 72 Commando but I would never touch the Amals again.
 

nortriubuell

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I went through everything you have wasting hours and hours on a new pair of premiers. The problem was only in the idle area, I solved almost all of it except it was still a little irregular at idle and when feeling the exhaust the left side would give a strong bap..bap..bap. The right side was a pitiful puff..puff..puff and nothing would change that. Any other throttle position and it ran very well. To finally rule out all other possibilities I installed a single 34mm Mikuni and both sides ran identically. I left the Mikuni in place so the owner could try it out. He was very happy but still wanted the dual Amals. I handed them to him in a box and wrote off about 20 hours of intense frustration, dead ends and wasted time. I told him I would work on any part of his 72 Commando but I would never touch the Amals again.
+1 here. I would love to run the dual amals; but the supposed "gains" are not worth the work. Plus with my single Mikuni on my 750 I got 60 mpg on a 200 plus mile trip. 60 freakin' MPG, I was stoked! ... and that was at steady 70 to 80 mph on I95 in Florida :D
 
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I have a good carb synching tool..Digi synch......and the innovate AFR meter and it's still a bear. Not to mention the need to R&R one pipe so I can install the AFR gauge. If only Amal would evolve and use the same pilot system that Mikuni uses.
Another topic..I have heard that running a single Amal 32 is OK but low on performance, How about a 36 Amal?
 

Scout63

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I had to do whatever it took to get to some kind of "square one" to begin to sort it out. I would have liked the new pair of carbs to drop on the bike and be magnificent , but I seem to have to buy everything twice and then fight with it. And I am a good technician but I am new to motorcycles. So I don't have 40 years of experience--I have been depending on the strategy of new parts giving me a good starting point, but it has not really worked that way. The pair of Wassel EVOs are scrap and potentially one Premiere may have to join the pile.
Sincerely,
Kara
I buy many parts twice and assemble/disassemble/assemble at least three times on new jobs. It just seems to be the way.
 
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Warm pipe like left side, good looking plug, decent running. No fight needed.

over rich RH carb

And I am a good technician but I am new to motorcycles.

carb technician? All kinds of carbs? throttle slide type?

The biggest clue for me is the old carb works and the new premier does not.
I would then not trust any part, passage, port, or orifice in that carb until verified it works. fuel level super low? or to high?
air leak at idle bowl/body/gasket passage? prevents idle circuit fuel draw? flat machined ? no bad machining scratches?
Only two circuits to screw up idle/low & main needle.
sounds like a traffic jam in the idle circuit....?
however:
"over rich RH carb "

black plug is the problem to solve . why to much fuel?

fuel level is universl and affects both low and high speed
 
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Since you already put on the old carb and it seemed to run fun I think we can rule out the electrical side. If it were me I’d take the carb apart again and really scrutinize all the passages. Not just with air and solvent but looking and poking.

These old bikes are never as simple as you think they should be. It’s a hobby so treat it as such. It also helps to have spare bikes so if one is holed up you have three or so other ones to choose from. :cool:
 

gortnipper

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To build on what swoosh said, try swapping the float bowls and floats R/L. That would eliminate the bottom half of the carb as an issue, or put it there.
 

bsaboss

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Can you swap the new carbs side to side, or is it essential the flat spots on the mounting flanges face each other? Obviously the tickler and adjusters will be on the inside and tricky to get to but if the problem changes sides at least you'd know the problem definitely lies with that particular new carb. If that's not possible try swapping the float bowl assemblies, jet blocks slides etc from one to the other (everything but the bodies) - at least that will identify or exclude those items as being the cause of the issue.
 

998cc

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Found swarf in the drillways of my new Premiers after taking them completely apart. After cleanout, they run great!

Grasping at straws here, but: Restricted/plugged RH muffler/silencer?

Regards,
998cc
 
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Surely if it is a new carburettor and it doesn't work, you take it back and either have it replaced or get a refund? That is the benefit of buying new.
 
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Found swarf in the drillways of my new Premiers after taking them completely apart. After cleanout, they run great!

Grasping at straws here, but: Restricted/plugged RH muffler/silencer?

Regards,
998cc
I fought a carb problem for a long time before I discovered that the mufflers had a restrictor plate built inside....it's outlet was maybe the size of a quarter at best. Substituted a pair of normal P-shooters and all was well. Check.
 
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