Carb Problems

[Beezerman]

Hi All
I have a 1959 golden flash iron head that I have just restored
Yesterday I took it out for the first time & it ran fine for the first ¾ of a mile, after that it just started to run rough. So today I stripped the carb down to see if there was a blockage but everything looked O.K. But my spark plugs were really sooty, so I changed the plugs & the bike started O.K. but still ran a little lumpy
The carb on the bike is a 389/1-1/8 that I bought from a dealer who said that it would bolt straight on, but looking at the numbers on the jetting everything looks wrong
Needle D
Pilot 20
main 300
needle jet 106
slide 3
My question is, do you think I could keep the body and just change the jetting to the ones quoted by Roy Bacon in his book BSA twins & triples, but he does not quote what needle to use 
Pilot 25
Main 240
Needle jet 106
Slide 3-1/2
Needle pos 3
Or should I just go for 376 1/16 with this jetting
Ron.

[muskrat]

G'day Ron,
              I does sound rich, as it's ok cold and plays up as it gets warmer.
The jets quoted from the Bacon book would be a good place to start. Stick with the needle you have, I don't know the letter codes for them but I'm sure someone here will.
Cheers.

[wilko]

Just buy a new needle jet and file 1/32 at a time off the curvature of your slide.Or your needle and seat could simply be not sealing properly in your floatbowl.

[Goldy]

Ron. I would experiment with what you have got first. Have you tried lowering the needle a notch or two to weaken it, that,s where I would start. According to the Amal reference book it should have a 250 main jet. all the best with it.

[tombeau]

If you're going to start changing jets and needle heights. Change one at a time, make a note of sizes and positions, so if it gets worse you can remember what it was set to before.

Roy Bacons book is a good start, but having said that I need a 20 pilot jet in mine, it wont run with a 25. These bikes are like kids, they're all different.

When I first got my A10 running I kept sooting up and killing plugs. It turned out to be the magneto, but I spent a lot o time fooling around with the carb before I found that out.
Good luck and keep us informed

[Beezerman]

Hi All
Thank you all for your feedback.  As well as posting on this site, I had also spoken to some A10 dealers and a couple of motorcycle mechanics. Plus some friends & the people at AMAL, so I have decided to go for a new one, the standard 376/80 but with the hard anodised slide and a stay-up float.  Unfortunately, AMAL said it could be a couple of weeks before it arrives - I will keep you posted.
Ron.

[Beezerman]

Hi everyone

Just to let you know that my carb came last Saturday morning, was on the bike by Saturday afternoon!  I took it out for a run around the block and it handled well, so I did another 25 miles just to make sure everything was OK.  I took out the spark plugs and they were a nice brown colour, so no more sooty plugs.  On Sunday I took it up to Sudbury, Suffolk, to a bike show.  I checked the plugs again when I got there and they were the same nice brown colour.  Spent a very nice day there... unfortunately... 5 miles from home the bike started to run very rough, with a loud popping noise on the left hand side exhaust.  so the very nice man from the AA took me home.  Next day, I took the rocker box and head off and found a very bent pushrod and a sticky valve.  I went back to the engineer who did the head job for me, and he said it was not enough clearance between the valve and guide.  So I ordered new valve and guides and pushrods and he redid the job for me.  And today, Friday, I finished putting it back together.  Tomorrow is test ride day.....

[muskrat]

G'day Ron,
              good to hear the new carb worked well. How much did it end up costing?
Sorry to hear of your other trouble. I try to er on the large side when it comes to valve stem to guide clearance. A little noise or blue smoke is better than a bent valve.
Good luck tomorrow, enjoy your ride.
Cheers

[Beezerman]

Hi Mustrat
IN the end £180.00 plus tax/p&p
Plus the parts for the head cost £150.00
Ron.

[RichardL]

Uh,  did head-job-man take any responsibility for completing the job without measuring stem/guide clearance.  If Ihad done such work on my own bike and had the problem,  shame on me.  If I pay a pro for that very thing that goes bad,  shame on him.

Richard L.

[rocket man]

hi i agree with Richard L take it back to the man who did the job he should be responsible for fixing it its not your
fault or get the money back you paid for doing it  and  dont use him again bad workmanship


dave

[Beezerman]

Hi everyone.  Yep, took it back the next day to the engineer.  He apologised profusely, and redid all the headwork and rechecked everything again (at no cost).  Also today I took the bike out for a test run, and it runs well, but I do have another question about tappets and will ask on the technical section.  regards  Ron.

[huddie]

Hi All, I was about to create a topic about plugs sooting up, did a search first whow!! what a minefield. Reading this thread makes me think it should be a new carb in standard set up. They dont come cheap though, do they. The prob with my bike is sooting up plugs, but no malfunctions, doesn't appear to be very economical though which is why I decided to investigate. Reserve ran out today before i got to the next petrol station. By my rough reckoning I did no more than 10 miles before the reserve ran out as well! My bike is a 1957 Gold Fash recently rebuilt with a rebuilt mag(SRM). The carb is old some scoring on the slide. The main is a 240, the needle is a 1065, needle position is 3 from the top. Plugs are Champion L82C. Air cleaner is pancake type with paper element. I have no probs starting or running, just sooty plugs. My plan of action was going to be 1. drop the needle, 2. change the plugs for the next hottest, 3 replace Needle and Jet with new ones. But before doing anything I would like your advice please.
Regards Chris

[shabashow]

I wish I could get 10 miles on my reserve, I only get 8!

[Smithgd]

If that bike ran fine for 3/4 of a mile, then started to run rough - I would be looking for Asian brushes in the Mag. They are soft carbon and will leave carbon tracks and cause rough running and eventuall stoppage. Does not sound like a carb problem.