Differences between Amal 389/4 and 389/1 carb

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SPRIDDLER
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Re: Differences between Amal 389/4 and 389/1 carb

Post by SPRIDDLER »

Bondy1066 wrote: I found nothing untoward when I stripped the carb down. I am going to put it back together and have another play.
Looking back at your two previous 'Help' requests (and comprehensive advice given) re. 'Sooty plug' from April this year when you mentioned that the bike and Brit bikes are new to you it seems you still have exactly the same carb issue. You had already stripped the carb without curing the problem. It seems that the bike has never run satisfactorily.
Have you looked at and followed the set-up/tuning guide in the AMAL link previously suggested? If you have and the correct spec'n jets, slide etc. are fitted it is unlikely that putting it back together as it was before (which you may have done incorrectly last time) and merely twiddling with the pilot screw ( 1 and 1/2 turns open is about right) will be the answer.
Have you forced aerosol carb cleaner or WD40 through the pilot drillings to verify that they are clear? (If not, for all the good twiddling with the pilot screw will do you may as well go down the shed and wave your willy out the window :roll: )
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G15 Roy
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Re: Differences between Amal 389/4 and 389/1 carb

Post by G15 Roy »

If it is old then just throw it away and buy a new one trust me I have spent days playing with old carb bits only last week i built two carbs form bits only to find a different problem each time, bought a new one the bike was transformed straight out the box.
Roy
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clive
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Re: Differences between Amal 389/4 and 389/1 carb

Post by clive »

How much of that red wine have you been at Sprids? However I would agree that twiddling the pilot screw will not work unless the little drilling that comes up just beyond the slide is clear. Having said that I have had recently had to drop the needle on my 600 twin from middle stetting to one lower as it was sooting up when tootling round town on just over tickover speeds. A fellow member recently phoned to say he had had to do the same on a 350 single. I know the normally wisdom is that the needle only comes into play well beyond 1/4 throttle but its sorted things for me, without noticeable affects on performance otherwise. Might this be something to do with changing fuel formulas?
clive
if it ain't broke don't fix
SPRIDDLER
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Re: Differences between Amal 389/4 and 389/1 carb

Post by SPRIDDLER »

clive wrote:How much of that red wine have you been at Sprids?
Hmm, good point, I've just done a sobriety test.....
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leswaller
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Re: Differences between Amal 389/4 and 389/1 carb

Post by leswaller »

G15 Roy wrote:If it is old then just throw it away and buy a new one trust me I have spent days playing with old carb bits only last week i built two carbs form bits only to find a different problem each time, bought a new one the bike was transformed straight out the box.
I agree totally, the old one will be worn out and whatever you do it will not be 100%. I had exactly the same experience as Roy, a new carb transformed the starting, the smoothness of the engine, the power and the fuel consumption. Well worth using a few beer tokens on a new carb.
Les
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