Amal 932: idle 2000 rpm, not less! (2014)

pierodn · Jun 28, 2014

The bike has the idle to 2000 rpm and I can't do anything to decrease!
The trottle stop screws are completely unscrewed and the pilots of the air are unscrewed by one and a half turn.
I might think that the cables are too short and the throttle slides fail to go down at the end of the stroke.
But, when the bike is idling if I unscrew the air pilot adjuster screws the engine loses speed and turns off.
What to check?
Thank you.
Piero

1up3down · Jun 28, 2014

Hi Piero!

check that your throttle cables are located fully down in the tubes at the carb tops

open the throttle half way and let it snap closed, can you hear the snap?

take the air filter off and look in the back of the carbs, are the slides all the way down?

are your lower cables adjustable, do they have threaded adjusters you can screw in to make longer?

does the upper cable have a little slack, if too tight that could be holding up the lower cables?

the air screws: leave them about one and a quarter turns out from full seated, not the problem

pierodn · Jun 28, 2014

1up3down said:
Hi Piero!

check that your throttle cables are located fully down in the tubes at the carb tops

open the throttle half way and let it snap closed, can you hear the snap?

take the air filter off and look in the back of the carbs, are the slides all the way down?

are your lower cables adjustable, do they have threaded adjusters you can screw in to make longer?

does the upper cable have a little slack, if too tight that could be holding up the lower cables?

the air screws: leave them about one and a quarter turns out from full seated, not the problem

Hi,
The threaded adjusters are all unsrewed (all into) so i cannot make they longer!
Thanks.
Piero

1up3down · Jun 28, 2014

ok

Pierro, do the top of your carb have threaded tubes that the cables go into?

is so, screws them fully down

Torontonian · Jun 28, 2014

Maybe the bodys are warped from overtightening ?

pierodn · Jun 28, 2014

Torontonian said:
Maybe the bodys are warped from overtightening ?

Hi,
What it means?
Ciao
Piero

1up3down · Jun 28, 2014

doubtful, as Pierro has a high idle problem and says his lower cables will not allow the slides to fully hit the bottom of the carbs

correct, Pierro?

pete.v · Jun 28, 2014

First step in carb setup, with the idle adjuster screws backed off (unscrew so the do not influence the slides), with the slides resting on the bottom, equalize the play in the cables with the cable adjusters.

Take the air filters off and press your fingers against the slides as you work the throttle to feel them just off the bottom. Screw the adjuster to get them to lift off the bottom exactly at the same time.

Go through the rest of the process as I assume you did before.

aceaceca · Jun 28, 2014

If you are running points with mechanical advance, check that the adv mechanism is not gummed up, broken, or stuck on full advance.

dennisgb · Jun 28, 2014

Check for manifold or adapter air leaks.

dynodave · Jun 28, 2014

1. Absolutely MUST have cable slack with the idle screws backed out. Both carbs both cables.
I had the same problem after installing new sealed in the bag AN cables (BSA regal not Joe S's AN) and they were TOO SHORT and held the slide open. I felt stupid since I know I did not follow rule one or I would have discovered the defect sooner.

pierodn · Jun 29, 2014

aceaceca said:
If you are running points with mechanical advance, check that the adv mechanism is not gummed up, broken, or stuck on full advance.

The bike has a new Boyer.
Ciao
Piero

pierodn · Jun 29, 2014

dynodave said:
1. Absolutely MUST have cable slack with the idle screws backed out. Both carbs both cables.
I had the same problem after installing new sealed in the bag AN cables (BSA regal not Joe S's AN) and they were TOO SHORT and held the slide open. I felt stupid since I know I did not follow rule one or I would have discovered the defect sooner.

Hi,
I hope this is the problem because the cables are news with adjuster screws all unscrewed.
The carbs are old bodies 932 Commando stock, but all the hardware is new.
Both carbs have the idle screws backed out.
The bike has a new boyer well setted.
I will desmount the air filter and i will ceck into.
Ciao
Piero

travelerjerry · Jun 29, 2014

pierodn said:
dynodave said:

1. Absolutely MUST have cable slack with the idle screws backed out. Both carbs both cables.
I had the same problem after installing new sealed in the bag AN cables (BSA regal not Joe S's AN) and they were TOO SHORT and held the slide open. I felt stupid since I know I did not follow rule one or I would have discovered the defect sooner.

Click to expand...

Hi,
I hope this is the problem because the cables are news with adjuster screws all unscrewed.
The carbs are old bodies 932 Commando stock, but all the hardware is new.
Both carbs have the idle screws backed out.
The bike has a new boyer well setted.
I will desmount the air filter and i will ceck into.
Ciao
Piero

Throttle Chamber portion in the body is worn out if throttle slides are all the way down. (My guess) Resleeve old carbs or replace with a different set. Had a high idle problem awhile back and replaced the old 932's. My high idle problems were gone.

concours · Jun 29, 2014

I had a new (top, single) cable, it was too short, I removed the adapter sleeve at the twist grip to gain more slack. It was a temporary fix, and when I fitted new carbs, I was able to re-install it, with ALL ADJUSTERS (carb cap, inline top cable) buried in. I'm puzzled as to why so many cables are shorter than original. :?:

Beach · Jun 29, 2014

I would make sure the slides are all the way down when slack in cable, check to see that the needles didn't slip out of place in the clip when installing and check the float level...

Towner · Jun 29, 2014

pierodn said:
The carbs are old bodies 932 Commando stock, but all the hardware is new

If you have new sliders as well, then you should ensure that they can be moved freely. Maybe they stick.

Ralf

ashman · Jun 29, 2014

If you have old bodies and have replaced all your needles and jets then maybe when you got new needles they could be smaller than the ones you replaced, I rebuilt my Amalsa lone time ago and when I replaced the needles the bike ran but would not idle under 2,000rpms, so did all the rechecking and everthing else was right but still idled fast, so I pulled the needles out and layed them beside the old one and sure enough the new ones were shorter, the bike shop had given me Triumph needles as we found out later and another trip over the other side of town, its esay to get parts mixed up at a shop when they are restocking parts all the time.

Ashley

Thomasdunstall · Jun 30, 2014

Hi everybody,

the bike with the idle at 2000 rpms is mine...

I found an interesting old post about cables lenght (2012)
anyone-buy-throttle-cables-lately-t13376.html
That's very disappointing...

I'm going to dismantle air filter box and tank this evening to check if, as we believe, the erratic idle is caused by too short throttle cables. We'll know in a couple of hours...

That's the bike, a '72 Roadster fully rebuild with my cousin Piero
Ciao

Amal 932: idle 2000 rpm, not less! (2014)

1up3down · Jun 30, 2014

bello!

Amal 932: idle 2000 rpm, not less! (2014)

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