Brand new 389

[morris]

Got fed up with the behaviour of the A10 ('58 SA, with '60 engine) as it more and more often, when going out for a ride and I dared to stop the engine, refused to start.
I also could never get the tickover right, it was always to fast.
I broke the piggybank, and forked out for a sparkling new 389 of the correct 1 1/8" size (as the old one was a 1" 376, and leaking all over the place in spite of changing all the gaskets twice)
It made a completely different bike, with a smooth lazy tickover, starts first kick when warm.
The carb came with a 30 pilot, 250 main, 106 needle jet, and 3.5 cutaway.
At first I couldn't get it started, but when changing the pilot to a 25, and putting the needle in 5th from top, it fired and seems to be doing the job since then, although I'm left with 2 annoying problems;
1/ starting from cold needs at least 10-15 kicks, and a lot of fiddling with tickler and choke
2/ when pulling out of a bend in a higher gear, it hesitates, and I have to change down and rev it to make it pull away easy (could be due to the needle to high though, so I'm going to lower it a notch to see what happens).
Anybody got another idea?

[morris]

Found the answer to problem #2. Screwed in the pilot jet 3/4 turn. Solved.
That leaves just the cold starting.
What procedures do you guys use to get it going from cold? (apart from saying a prayer whilst hopping around the bike three times on one leg and touching the rabbits foot in your pocket when kicking)

[muskrat]

Mine all start with just a tickle (same as the missus  ), no choke. But their concentrics.
Cheers

[fido]

Try giving it more throttle when starting from cold. This worked with my A7 since the last magneto rebuild.

[morris]

Thanks Musky, but stopped tickling her. The wife got suspicious.

Instead, I followed Fido's suggestion.
I now give it 2-3 kicks with trottle and choke closed to prime the carb, then open the choke slightly, open the throttle 1/4 turn, and give it a good kick. Seems to work each time until now. (Keep the rabbits foot in my pocket though, just in case....)

Noticed the flag under my posts for a couple of days now. To he who added it, many thanks, as I tried several times bud didn't succeed.

[Big Nick]

i have also put on a new mono block  and it's being a pain ! i think my next step is to retry the consentric i took off

[KiwiGF]

hi morris, ive got a worn 389 on mine same jets as you, but no choke is fitted, from cold I just tickle the carb until petrol comes out the tickler and give it about 1/4 throttle and she starts fine first or second kick, i have a bth mag but that may or may not make for better starting.

The secret with mine is give is to use a good handful of throttle hot or cold, she wont start otherwise.

a choke might be needed in a colder country of course!

[morris]

Thanks Kiwi.
It seems my new Amal needed a running in period.
In the beginning I had to fiddle a lot with tickler, choke and throttle to get it going, but the last couple of months it behaves faultlessly. When the engine is cold I just have to close the choke, don't touch the throttle and it never fails to start first kick.
When hot, I open the throttle 1/4 turn, one kick gets it going.
I do run the bike at least 3-4 times a week so there's always fresh petrol in the carb.
Great excuse for the wife; Sorry honey, but we can't go to your mum today because I need to get some fresh petrol in the carb.

[A10Boy]

I have a 376 with standard Flash settings. All it needs is a good tickle [so fuel comes out of the breather], half choke, 1/8 turn on the throttle and it starts first kick almost every time from cold. Hot or warm, tiny tickle no choke starts first kick. Happy days 

[duTch]

 Hiya Morris,
              Running same(25,106,250,3-1/2,cheap K&N copy to keep rocks out) and no choke as KiwiGF, but I have a K2F, BP6ES plugs, had a 25 pilot, went down to 20, needle top notch/lean- still running rich, may need to up the cutaway??
 Still starts/runs fine trekkin' in town, on the freeway but sometimes goes to crap when just plugging round(if you know what I mean), and seems to falter a bit in the transition from idle/pilot to cutaway phase.....weird stuff
 
I'm curious though, I had the notion that the 389's were introduced for the Dark Side - A65 (in very SMALL letters),
I'm just using it 'cos it's what I have.

 cheers

[bsa-bill]

My 61 flash came with a 389 (in 1961)

[RichardL]

Great excuse for the wife; Sorry honey, but we can't go to your mum today because I need to get some fresh petrol in the carb.

Mine is: "I'm just going on a short run to keep it oiled," by which I mean to put the sump oil back up into the tank.

Richard L.

[morris]

Still starts/runs fine trekkin' in town, on the freeway but sometimes goes to crap when just plugging round(if you know what I mean), and seems to falter a bit in the transition from idle/pilot to cutaway phase.....weird stuff

Weird indeed Dutch, I'm having the same problem as you mentioned, there seems to be a flat spot between idle and cutaway.
It only shows itself when pulling off in a higher gear, for example when slowing down for a bend and opening up the throttle without shifting down.
When I screw in the pilot air screw about 1/2-3/4 turn, it doesn't do it anymore, so it looks like its not getting enough fuel.
But then the right cylinder starts running rough at tickover, and when I give it more air by screwing the air screw back out, it runs better, but got the above symptoms again, so it looks like I'm in a catch 22 situation here
Wile on the subject, the left spark plug always has a nice brownish colour, while the right one is always sooty, so it looks like I'm having a richer mixture in the right pot.
I've been browsing the forum on the subject, and found some good info which I am going to check.
Does anybody have some good experience with the anti-bias gasket?
Thanks,

[muskrat]

Try lifting the float/fuel height a tad (1/32") or 1/2 size richer slide.
Cheers

[Topdad]

Don't know about 389's I had one on my bike when I first put her back on the road ,she just didn't like it very lumpy flatspots when opened up and spitbacks on the overun  was really putting me off the bike to be honest so bought a concentric and became a different bike and still is 7 yrs on.. Was told that the 389 came of a velo but still had jets to suit an A10 just changed the pilot but no good mememorys of it BobH.