Amal carbs and spark plugs issues and concerns

Yes, the choke is counterintuitive. The choke handle will pull the cables tight leaving the handle perpendicular with the handlebars. If the lever is in line with the handlebars, it is choked.
 
MichaelB said:
Yes, the choke is counterintuitive. The choke handle will pull the cables tight leaving the handle perpendicular with the handlebars. If the lever is in line with the handlebars, it is choked.
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Man am I about to have me some fun
I'm so excited. The choke lever that was on the bike was old and a left hand unit in the right side so that the lever was pointed parallel with the bars. So I bought a right side unit and replaced the old one, not thinking that it was tensioned before I removed it. Thus parallel is aligned with the bars not perpendicular. Thus why the engine was running so rich and blackening the plugs and cutting out and so on. New plugs and a uncooked motor may just give me back that well tuned ride I was just falling in love with. At least that's my hope. Will keep you posted.
 
arcpoint said:
Man am I about to have me some fun
I'm so excited. The choke lever that was on the bike was old and a left hand unit in the right side so that the lever was pointed parallel with the bars. So I bought a right side unit and replaced the old one, not thinking that it was tensioned before I removed it. Thus parallel is aligned with the bars not perpendicular. Thus why the engine was running so rich and blackening the plugs and cutting out and so on. New plugs and a uncooked motor may just give me back that well tuned ride I was just falling in love with. At least that's my hope. Will keep you posted.
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That's unchoked not uncooked (@#*!! spell correction)
 
In response to OP comments: The Amal idle and mid throttle circuits have no effect on top end. Top end is all main jet. It does appear that your sooty plugs were choke induced. If your Boyer was added in '21, it is likely a "Micro Digital" It's a blue box. It does require a resistor plug, or a resistor cap, not both.
 
arcpoint said:
Man am I about to have me some fun
I'm so excited. The choke lever that was on the bike was old and a left hand unit in the right side so that the lever was pointed parallel with the bars. So I bought a right side unit and replaced the old one, not thinking that it was tensioned before I removed it. Thus parallel is aligned with the bars not perpendicular. Thus why the engine was running so rich and blackening the plugs and cutting out and so on. New plugs and a uncooked motor may just give me back that well tuned ride I was just falling in love with. At least that's my hope. Will keep you posted.
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You are not the first to get the choke the wrong way around. I should have thought of that too.

But unfortunately now I'm probably going to be the bearer of bad news.

Almost all the modern choke lever replacements are rubbish. They do not tighten down properly and if you tighten them hard enough to stay up you need a spanner to move them. And if they are lose enough to move they will vibrate on in a few km of running.

I fought a new lever for months before reassembling another one from a box of old original parts. Which worked perfectly day one and continues to do so three years latter.

The problem with the new levers is the stack of parts and spring washer don't sit together with the right clearances. A lot of work with a file might fix it. Or you may find your old lever can be cleaned up with a few of the parts from the new one.

So keep an eye on your new lever. You may find you set it off. And 5 km down the road it's on again.

It's called endearing 🤣🤣🤣
 
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johnm said:
You are not the first to get the choke the wrong way around. I should have thought of that too.

But unfortunately now I'm probably going to be the bearer of bad news.

Almost all the modern choke lever replacements are rubbish. They do not tighten down properly and if you tighten them hard enough to stay up you need a spanner to move them. And if they are lose enough to move they will vibrate on in a few km of running.

I fought a new lever for months before reassembling another one from a box of old original parts. Which worked perfectly day one and continues to do so three years latter.

The problem with the new levers is the stack of parts and spring washer don't sit together with the right clearances. A lot of work with a file might fix it.

So keep an eye on your new lever. You may find you set it off. And 5 km down the road it's on again.

It's called endearing 🤣🤣🤣
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If that happens I'll throw it in the road and put the old trashed one back on because I know it stays put. Was def out of place with it's pitted chrome among all the nice blingy finery everywhere else, but hey, in this case function over form will rule the day. I just gotta get out and ride without an onslaught of unwelcome annoyances that can easily be averted.
 
arcpoint said:
If that happens I'll throw it in the road and put the old trashed one back on because I know it stays put. Was def out of place with it's pitted chrome among all the nice blingy finery everywhere else, but hey, in this case function over form will rule the day. I just gotta get out and ride without an onslaught of unwelcome annoyances that can easily be averted.
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FYI. Many owner/operators ditch the chokes on these bike entirely. Not strictly needed, just a good tickle each carb and running first few minutes with throttle off idle to save from cold flame outs. Simplifies life. No bar lever, cable/cable junction box splitter/box to carb cables. No choke spring and choke slider in the main throttle sliders.
 
Tornado said:
FYI. Many owner/operators ditch the chokes on these bike entirely. Not strictly needed, just a good tickle each carb and running first few minutes with throttle off idle to save from cold flame outs. Simplifies life. No bar lever, cable/cable junction box splitter/box to carb cables. No choke spring and choke slider in the main throttle sliders.
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Yeah, the PO and I weren't using it at all, just leaving the lever on for posterity. Not needed. But when I changed it out, I wasn't aware (or paying attention to my own actions) and failed to realize that it must be cranked back to be off. Prob get rid of it altogether.
 
arcpoint said:
Yeah, the PO and I weren't using it at all, just leaving the lever on for posterity. Not needed. But when I changed it out, I wasn't aware (or paying attention to my own actions) and failed to realize that it must be cranked back to be off. Prob get rid of it altogether.
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In my case my bike came to me as a HiRider which I immediately converted to Roadster configuration, dropping chokes at same point b/c would have needed new cable length from hirider Ape hanger bars to Roadster bars. Didn't bother and never looked back.
 
Tornado said:
In my case my bike came to me as a HiRider which I immediately converted to Roadster configuration, dropping chokes at same point b/c would have needed new cable length from hirider Ape hanger bars to Roadster bars. Didn't bother and never looked back.
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Was there any trick to it or do you just follow the cables and remove accordingly?
 
arcpoint said:
Was there any trick to it or do you just follow the cables and remove accordingly?
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If you have never taken Amal carbs off of the manifolds and taken them apart then you might want to leave them be
If you do decide to remove the choke assembly make sure you block the hole in the top of the carb where the cable enters to stop it pulling air in
 
baz said:
If you have never taken Amal carbs off of the manifolds and taken them apart then you might want to leave them be
If you do decide to remove the choke assembly make sure you block the hole in the top of the carb where the cable enters to stop it pulling air in
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What do you block the hole with, a screw?
 
arcpoint said:
If that happens I'll throw it in the road and put the old trashed one back on because I know it stays put. Was def out of place with it's pitted chrome among all the nice blingy finery everywhere else, but hey, in this case function over form will rule the day. I just gotta get out and ride without an onslaught of unwelcome annoyances that can easily be averted.
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IMHO, there's only one place for the choke on Amal MK1 carbs - the trash can! They are simply not needed! A few will try to say I'm wrong, but then I submit that their carbs are not set right or they have ignition :D

Every British bike I've owned since 1968 and almost everyone I've built had no choke. The only exception is when the owner wants to show the bike. Simply throw away all choke components and plug the hole in the top of the carbs. The Amal part number for the "screwed plug" to do that is 4/137A or you can just close it with silicone.
 
CanukNortonNut said:
Amal engineers put the chock slides in there for a reason. I guess its for Us Northern riders past the 49th. :cool:
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I have to agree with Greg M and others on the choke observation.
If properly tuned my 850 will fire first kick even when dead nuts cold (21°F) with the choke inlet hole blocked and the rest of it sitting in the parts bin.
 
A well tuned 'Stock' Commando is a nice ride.
The original engineers had a lot of it right.
Before running down the rabbit hole of endless mods and upgrades, I suggest to get it running as good as you can with what you have. Sounds like you have good bones with a recent refurb.

Good Luck!!!
 
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My Commando is a pain to warm up without the chokes. It works perfectly when the chokes are used though.
Don't get rid of the chokes until you have tried starting and riding the bike on a frosty morning somewhere in the Sierra Nevadas!
Even on a 50 f morning the choke is needed for a minute or two on my Mk3.


Glen
 
CanukNortonNut said:
Amal engineers put the chock slides in there for a reason. I guess its for Us Northern riders past the 49th. :cool:
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Yes, I'm guessing because people expected it - a marketing issue. They also made available from the beginning the plug to eliminate them!

I rode a Triumph T100 to college for two years with Amal MK1 carbs, no chokes and Energy Transfer ignition (no battery, not a magneto) near St Louis. Even at -10F - no choke needed (yes, damned near froze to death). It was a good thing that the chokes were not needed - I certainly could not afford the parts to add them!

Today, life is easy - stick in Tri-Spark properly timed, be sure you have good carbs that are properly tuned, add a reed valve breather, kick once or twice and ride.

And of course, don't be poor and stupid and ride with improper clothes in freezing weather :)
 
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