Joined: 15 Apr 2004 Posts: 898 Location: Boulder, CO
Posted: Sun Aug 08, 2004 7:01 pm Post subject: Those ratty old amals
I spent some time this weekend cleaning up my tired old amals. First I soaked the bodies in carb cleaner, then I soaked them in white vinegar. The vinegar worked great on the hard scale deposits that the carb cleaner didn't touch. I found it very difficult to get access to the clogged pilot jets so I drilled out the blanking plugs behind them. Now I can see daylight thru the pilot jets and the pilot fuel circuit is clear on both carbs.
But, and this brings me to my question, I tried to push a single strand of 12 awg stranded wire thru the pilot jets as suggested on another thread and I could not get it to go on either carb. Does that mean my pilots are still partially clogged? Should I get some finer gauge wire that will push thru and work my way up to the 12 ga, or just put them back together as they are and hope for the best?
The hole your trying to clean is .017 it's a #25 jet. I use a piece of music wire .012 and some solvent. Don't want to scratch up the finnish inside the hole. If it's real bad a .016 drill bit can be used but that would be a last dich effort. Time to go get a guitar string, they are sold by gadge and have the decimal equivalants on the packages start checking around. make sure you do a nice job resealing the blancking holes if they leak air they can cause funny running. Good luck Debby. norbsa
Joined: 14 Jun 2003 Posts: 667 Location: HOUSTON, TEXAS
Posted: Mon Aug 09, 2004 9:07 am Post subject:
Debby,
I have never had to use anything but carburetor cleaner to clear the pilot jets on any of my AMALs. If you used Berryman's carb cleaner, it's pretty strong stuff and you can feel confident that your pilot jets are clean.
As nrobsa cautioned, be careful not to scratch / damage the pilot jets with wire, drill bits, etc. At this point, I would assemble everything and give it a go!
Joined: 15 Apr 2004 Posts: 898 Location: Boulder, CO
Posted: Mon Aug 09, 2004 11:19 am Post subject:
So, today's Norton-related scavenger hunt was a trip to the music shop for a guitar string, plain steel, .012" diameter. Wasn't sure how I was going to explain it to the music store guy but I just asked for it by diameter. The one I got set me back $0.80 USD. It can be tuned for a B, D, or E note. The things I learn working on this bike!
Joined: 15 Apr 2004 Posts: 898 Location: Boulder, CO
Posted: Mon Aug 09, 2004 7:29 pm Post subject:
Well, the guitar string did a nice job. It's a lot stiffer than copper wire; much easier to push through.
Now to seal off the blanking hole - I have a couple of old airscrews. Was thinking of cutting the ends off, fitting new orings, and pushing them in to seal the holes. Is that likely to give a sufficient seal or will I need something that's a tighter fit?
Posted: Tue Aug 10, 2004 8:27 pm Post subject: Amals
When you are reassemblying your carbs make sure the float chamber body fits closely to the carburetter body. If you over tighten the screws you will cause an air leak to your idle circuit.
Joined: 24 Dec 2003 Posts: 362 Location: Brisbane, Australia
Posted: Sun Sep 19, 2004 1:43 am Post subject: Some Humour
Some Humour
After all the teething problems, thought this might be a laugh.
Carburetor Operation (From a Norton Colorado Newsletter)
The basic secret of carb function is that inside each carb are thousands of tiny gnomes; each with a small bucket. As you open the throttle, more of these gnomes are allowed out of their house and into the float bowl, where they fill the buckets and climb up the carb's passages to the intake, where they empty their buckets into the air stream.But, if you don't ride the bike for a while, bad things can happen.
Tiny bats take up residence in the chambers of the carb, and before long the pas-sages are plugged up with guano. This creates a gnome traffic jam, and so not enough bucketfuls of fuel can get to the engine. If it gets bad enough, the gnomes simply give up and go take a nap. The engine won't run at all at this point.
Sometimes you'll have a single dedicated gnome still on the job, which is why the bike will occasionally fire as the gnome tosses his lone bucket load down the intake.There has been some research into using tiny dwarves in modern carbs. The advantage is that unlike gnomes, dwarves are miners and can often re-open a clogged passage. Unfortunately, dwarves have a natural fear of earthquakes, as any miner should. In recent tests, the engine vibrations caused the dwarves to evacuate the Harley Davidson test vehicle and make a beeline for the nearest BMW dealership. Sadly, BMW's are fuel injected and so the poor dwarves met an unfortunate end in the rollers of a Bosch fuel pump.
Other carb problems can also occur. If the level of fuel in the float bowl rises too high, it will wipe out the poorer gnome housing in the lower parts of the carb. The more affluent gnomes build their homes in the diaphragm chamber, and so are unaffected. This is why the bike is said to be “running rich”.If the fuel bowl level drops, then the gnomes have to walk farther to get a bucketful of fuel. This means less fuel gets to the engine. Because the gnomes get quite a workout from this additional distance, this condition is known as “running lean”.The use of the device known only as the ?choke' has finally been banned by PETG (People for the Ethical Treatment of Gnomes) and replaced by a new carb circuit that simply allows more gnomes to carry fuel at once when the engine needs to start or warm up. In the interests of decorum, I prefer not to explain how the ?choke' operated. You would rather not know anyway.
So, that's how a carburetor works. You may wish to join us here next week for basics of electricity, or “How your bike creates cold fusion inside the stator, and why the government doesn't want you to know about it.
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At the end of 1967 the Norton Commando was announced.
The Norton Commando was greeted with a certain amount of scepticism because on first sight the commando appeared to comprise of the old Norton Dominator twin cylinder engine mounted at an inclined angle in a set of new cylinder parts.
It was not realized that the new Norton Commando Isolastic method of engine suspension damped out all engine vibration and produced a machine which had uncanny smoothness for a vertical twin. In due course the critics were silenced and the Norton Commando had the distinction of being regarded as the first of todays so called superbikes. There can be little doubt that the original design concept of the Norton Commando has proved correct, since comparatively few modifications of any real consequence have been made since production commenced during 1968.
Now nearly 40 years later Norton Commando riders like us are a breed of our own, and as far as we are concerned its still more fun to go for a blat on the old Norton Commando, and fast. As a Norton Commando owner and enthusiast, my goal here is to promote and give credit to those who keep the Norton name going.
It is more deserving to give credit to the Commando itself, for after all these years it continues to be respected. The original Commando designers like John Favill are those who deserve the credit for developing this incredible motorcycle.
The Norton Commando Roadster and Interstate of the late seventies, never died. Although the Norton Villiers factory dispersed the tradition lived on. Today Kenny Dreer in the USA is developing the new 952 CC Norton. What a great looking bike this is, and its engineering is still based on the original layout. It will be interesting to see how the new 952CC Norton does in todays tough motorcycle market. One thing is for sure, I would own one if I could afford it.
Some Humour