Amal 932 Set-up and Tuning questions

Niagara850 · Jun 13, 2011

Attempting to set-up and sync Amal 932 carbs (new) on a 74 859 Mk2. I have read a number posts, Amal set-up and Bushmans tuning guides. Set up using the run on right side only then left side and together and fine tune method. The bike seemed to run well at speed but wouldn't start or idle the same way twice. Would idle at around 1500 when warm, did field adjustments when hot and had it idling at 1000 and running smoothly with the occasion bang in the right exhaust on a nice 50 mile run through towns and open highway. Restarting after short stop (20 mins) was difficult... lots of kicking , sporadic firing before finally running, wouldn't idle until driven for a few miles. So decided to readjust carbs from scratch.
1) Discovered that left carb slide moved up well before right, so sync required. Went to to use the Bushman method but cable adjustment won't go far enough to set slides to they just appear in the throttle opening, they disappear well up. Set them to move by eye and will use the drills in slide to fine tune. Seems like a good way to sync the slide movement. I expect the slide screws will have to be turned in a turn or two to get it to idle with the throttle closed
2) Where do you set the choke airslide position? When I adjust to just touch the bottom of the throttle opening they don't retract all the way up into slide when the cable is tightened. If set to just disappear they are not exposed lower than the slide when the throttle is closed.

swooshdave · Jun 13, 2011

Niagara850 said:
Attempting to set-up and sync Amal 932 carbs (new) on a 74 859 Mk2. I have read a number posts, Amal set-up and Bushmans tuning guides. Set up using the run on right side only then left side and together and fine tune method. The bike seemed to run well at speed but wouldn't start or idle the same way twice. Would idle at around 1500 when warm, did field adjustments when hot and had it idling at 1000 and running smoothly with the occasion bang in the right exhaust on a nice 50 mile run through towns and open highway. Restarting after short stop (20 mins) was difficult... lots of kicking , sporadic firing before finally running, wouldn't idle until driven for a few miles. So decided to readjust carbs from scratch.
1) Discovered that left carb slide moved up well before right, so sync required. Went to to use the Bushman method but cable adjustment won't go far enough to set slides to they just appear in the throttle opening, they disappear well up. Set them to move by eye and will use the drills in slide to fine tune. Seems like a good way to sync the slide movement. I expect the slide screws will have to be turned in a turn or two to get it to idle with the throttle closed
2) Where do you set the choke airslide position? When I adjust to just touch the bottom of the throttle opening they don't retract all the way up into slide when the cable is tightened. If set to just disappear they are not exposed lower than the slide when the throttle is closed.

The drill method worked great for me. First (w/o the drills) turn out the throttle stop screws and then back in until they are just barely touching the slides. Then I used the drills (in my case the airbox screws were perfect but I think you have the plastic box on the 2A) and adjusted using the adjusters on the tops of the carbs until the drills (screws) moved together. I then screwed in the throttle stops evenly. Started bike and adjusted for idle speed.

You're in the cold North so you may need the chokes, especially for ice racing. Me, I just left them out. :mrgreen:

Start bike, hold throttle for 30-60 sec and it will idle by itself.

I used a Colortune to get the mixture pretty good. I guess other people do it some other way.

Erratic behavior for me was caused by two things: Boyer stator was loose. Messed up the timing. Made it hard to start. Retimed and tightened. And then carbs were loose causing intermittent airleak. Point is it could be electrical or carburation, never discount either. :mrgreen:

travelerjerry · Jun 13, 2011

If carbs are synced, your symptoms remind me where I had a loose jet holder. Or pilot air jet could be plugged, need a #78 drill bit attached to a toothpick and (make reference mark on air pilot screw slot to carb body) unscrew pilot adjuster screw and insert drill bit in carefully to clean out orfice. Then I use "Deep Creep" carbon cleaner spray and give it a blast with nozzle tube fully in, you should hear the spray sound coming out the intake. Of course you mentioned new carbs. These are my first thoughts. Good Luck. I'm sure someone else will chime in.

For every cause there is a reason. Ride Safe.

Niagara850 · Jun 13, 2011

OK! the drill method made syncing the slides together easy as well as setting throttle stop screws to point where they just touch the slides. Turned the pilot screws out 1.5 (they were very close to 1.5 to begin with) She's ready to start but that will have to wait till tomorrow. Game 6 of the Stanley Cup is on... Boston is laying a beating on Vancouver, Thomas is stoning the Cannuks. Only one player carried off the ice so far.

swooshdave · Jun 13, 2011

Niagara850 said:
OK! the drill method made syncing the slides together easy as well as setting throttle stop screws to point where they just touch the slides. Turned the pilot screws out 1.5 (they were very close to 1.5 to begin with) She's ready to start but that will have to wait till tomorrow. Game 6 of the Stanley Cup is on... Boston is laying a beating on Vancouver, Thomas is stoning the Cannuks. Only one player carried off the ice so far.

Be aware that there are reports that some of the new Amals may have crap in them, blocking some of the passages. If I had new carbs I would clean the ever-loving' out of them first.

Bruins withstood the final assault, Game 7 is next.

Niagara850 · Jun 14, 2011

swooshdave said:
Niagara850 said:

OK! the drill method made syncing the slides together easy as well as setting throttle stop screws to point where they just touch the slides. Turned the pilot screws out 1.5 (they were very close to 1.5 to begin with) She's ready to start but that will have to wait till tomorrow. Game 6 of the Stanley Cup is on... Boston is laying a beating on Vancouver, Thomas is stoning the Cannuks. Only one player carried off the ice so far.

Click to expand...

Be aware that there are reports that some of the new Amals may have crap in them, blocking some of the passages. If I had new carbs I would clean the ever-loving' out of them first.

Bruins withstood the final assault, Game 7 is next.

I blew all the passages with air and carb cleaner before installing and the seems to be clear. The threads for the banjo bolt on one was slighly buggered. QC is not Amals strong point

Game 7 should be a Barnburner

Niagara850 · Jun 23, 2011

Well I've run her close to 500 miles now to gauge my tuning sucess

- set the choke airslides to as low down as they would go which is almost touching the bottom of the carb throat. They almost disappear into the top
- used the drill method to sync the cables and find the point where the slides just touch the screws
- turned the slide screws in 2 turns each to get her to start and warmed her up good
- ran left side only , then right side with the other plug grounded to get each side to idle at 1000 rpm, managed to keep the slide screws the same on each and fiddled with the airscrews to find the sweet spot. They were both within a 1/4 turn of 1.5 x out
- restarted on both cylinders and readjusted the slide screws out evenly to bring her down to 1000 rpm, gave good 50 mile run and made slight adjustments (always have screwdiver accompany cell phone in pocket) Seemed to need to have a couple of tanks of gas run through before the odd chuffing disappeared.

Result - Run nicely now. Starts on first kick most time when cold with a good tickling , no more than two. Have to keep a gentle hand on the throttle when cold for a few mins to get it to idle on its own. Starts one kick when warm. Pulls strong WOT, can putt slowly in a parking lot. No banging in the pipes, no bucking or hestitation. Happy

Now to improve front brake and get her to leak less oil

swooshdave · Jun 23, 2011

Niagara850 said:
Well I've run her close to 500 miles now to gauge my tuning sucess

- set the choke airslides to as low down as they would go which is almost touching the bottom of the carb throat. They almost disappear into the top
- used the drill method to sync the cables and find the point where the slides just touch the screws
- turned the slide screws in 2 turns each to get her to start and warmed her up good
- ran left side only , then right side with the other plug grounded to get each side to idle at 1000 rpm, managed to keep the slide screws the same on each and fiddled with the airscrews to find the sweet spot. They were both within a 1/4 turn of 1.5 x out
- restarted on both cylinders and readjusted the slide screws out evenly to bring her down to 1000 rpm, gave good 50 mile run and made slight adjustments (always have screwdiver accompany cell phone in pocket) Seemed to need to have a couple of tanks of gas run through before the odd chuffing disappeared.

Result - Run nicely now. Starts on first kick most time when cold with a good tickling , no more than two. Have to keep a gentle hand on the throttle when cold for a few mins to get it to idle on its own. Starts one kick when warm. Pulls strong WOT, can putt slowly in a parking lot. No banging in the pipes, no bucking or hestitation. Happy

Now to improve front brake and get her to leak less oil

I think you got it!

phsDommie · Jun 23, 2011

Well done! Sounds like you have a nicely running Commando. One thing you mentioned earlier on I thought might be helpful - that it is difficult to start when warm. My bike starts on the first kick every time when cold - without choke - as long as I've flooded both carbs. It idles beautifully without touching the throttle. After a run, I had some difficulty with starting until I learned to avoid the flooding when hot - i.e not to tickle the carbs at all. Now it starts with the first kick both when cold and when warm/hot.

Paul.

L.A.B. · Jun 23, 2011

Niagara850 said:
set the choke airslides to as low down as they would go which is almost touching the bottom of the carb throat. They almost disappear into the top

Personally, I would set the choke slides so they completely disappear when 'OFF' because using the chokes for starting is often unnecessary, many owners remove them completely.

Niagara850 · Jun 23, 2011

phsDommie said:
Well done! Sounds like you have a nicely running Commando. One thing you mentioned earlier on I thought might be helpful - that it is difficult to start when warm. My bike starts on the first kick every time when cold - without choke - as long as I've flooded both carbs. It idles beautifully without touching the throttle. After a run, I had some difficulty with starting until I learned to avoid the flooding when hot - i.e not to tickle the carbs at all. Now it starts with the first kick both when cold and when warm/hot.

Paul.

When to tickle and how much that is the question ! I've trying not to flood in the various stages from cold to hot. The hard starting when hot is what prompted me to get in there and readjust. My finding has been similar to your experience. Cold - airslides down, big tickle, good gush of gas. Warm but can hold my hand on the engine, no air slide, slight tickle just till I see little wisp of gas from the plunger. Hot, no airslide, no tickle. I'll experiment with more tickle when cold and see it she idles on it own right off when cold

swooshdave · Jun 23, 2011

Niagara850 said:
phsDommie said:

Well done! Sounds like you have a nicely running Commando. One thing you mentioned earlier on I thought might be helpful - that it is difficult to start when warm. My bike starts on the first kick every time when cold - without choke - as long as I've flooded both carbs. It idles beautifully without touching the throttle. After a run, I had some difficulty with starting until I learned to avoid the flooding when hot - i.e not to tickle the carbs at all. Now it starts with the first kick both when cold and when warm/hot.

Paul.

Click to expand...

When to tickle and how much that is the question ! I've trying not to flood in the various stages from cold to hot. The hard starting when hot is what prompted me to get in there and readjust. My finding has been similar to your experience. Cold - airslides down, big tickle, good gush of gas. Warm but can hold my hand on the engine, no air slide, slight tickle just till I see little wisp of gas from the plunger. Hot, no airslide, no tickle. I'll experiment with more tickle when cold and see it she idles on it own right off when cold

The amount of tickle won't affect the cold idle, just the cold start. For me with no airslides I start and hold the throttle at about 2k for 30 seconds. It'll idle then. Still needs a little more to warm up.

Try this, key off, tickle until just a little gas comes out. Kick through. Tickle again until just a little gas comes out. Key on. Kick.

No tickle when warm!

The coldest I've started it was about 50º F without airslides. So far. No problem. Don't really want to ride in much colder than that. :mrgreen:

bwolfie · Jun 23, 2011

swooshdave said:
Don't really want to ride in much colder than that. :mrgreen:

Around here the warm season is so short, if I can get it started and the snow isn't too deep, i'm riding. 30 degree riding isn't too bad with coveralls on.

Hobot · Jun 23, 2011

My own fumbles tend to agree with

Cold - tickle till wet shows, no need to dribble but hard to avoid, choke totally optional. very minimalist throttle opening.
Half warmed - 1/4 throttle open and maybe a 2-3 count tickle short of wet showing.
hot- 1/8 cracked throttle no tickle no choke.

They should start on first spark, which happens faster on contact breakers than electronic d/t 2 trigger signals to wake up. After you get used to your 1st kick ritual and it don't on first kick, suspect key off, fuel taps closed or some connection failed before wasting more effort. Can't forget could mean crap in fuel and carb again too.

Coldest I started a Boyer Combat was in 20' F with thick frost on seat sitting in yard at midnight. Flood level tickled tiny crack throttle kicked half dozen times with some firing each time till jugs warmed up enough vaporize enough fuel to run, then over rich coughing and sputtering for ~minute to get normal response to throttle and shoved off, no chokes installed thank you. But choke lever is just so cute will put in back on Trixie with a dead end cable just for factory showing.

DogT · Jun 23, 2011

I find it's really hard to flood the Norton. Not like the chain saw. Tickle never seems to hurt anything for me, but just so fuel shows up on bowl to body gasket if any warmth at all. Always seems to need good flood to drip on cold start, but warm and not long between runs starts right up without a tickle. In between is your shot.

Never kick more than 4 times, something is wrong.

Dave
69S

Amal 932 Set-up and Tuning questions

Niagara850

swooshdave

travelerjerry

Niagara850

swooshdave

Niagara850

Niagara850

swooshdave

phsDommie

L.A.B.

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Niagara850

swooshdave

bwolfie

Hobot

DogT

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