Standard carb. set up

Has anybody on this forum NOT had a problem with their Amal Carbs. Mine has always had the twin Carb. Mk.1 set up & I have never had a problem. Always set them up myself. As for slide wear, it has never bothered me unless it affects the tickover.
Comments please.

Umm.... isn't slide wear affecting tickover a problem? That's probably the biggest complaint people have with Amals.

There's also the pilot jet and those itty bitty holes in the carb body that have a tendency to get clogged. Every Amal owner will have to deal with that at some point. So.. if you don't mind having them sleeved when they wear, and you don't mind spraying and poking jets once in a while.. Amals are fine.

Amals are, probably, the most primitive carburetor in current manufacture; I have new ones fitted to my Mk III. I agree with Maylar and would add that Amals are also very sensitive to torque on their mounting fasteners. The slide bore on my left carb went oval even after carfully torquing it; good thing I had a "spare" lefthand carb body. I now have chrome slides. I admit that they "work" and while on the needle or main jet appear to work well.

Tuning an Amal is easy, syncing a set of Amals is easy, jetting an Amal is very straightforward, but compared to a Mikuni or a Keihin they are CRUDE. What would be really cool is fitting a Webber DCOE, anyone done that?

RS

Only the usual blocked idle jets, worn slides and bodies. My opinion is when they are set up properly and the slides are synched for even lift and idle they are not a problem IF you fit chromed slides. I replaced my 73 carbs in 99 with new items and while they worked OK for a couple of years the slides wore of course and so in February I replaced the bodies and needle jets and added chromed brass slides. These changes sent mileage (imperial gallons)from 55-60 to 65+ and I moved the needles up since I felt it was bit weak after getting 70 running in new rings. These are the new Amal castings from new tooling and the only issue I had was that the old floats got stuck between the casting where the pin sits.
I never found the synch settings change much unless new cables were fitted and needed settling in.
Jim Comstock in the US fitted a DCOE some years ago but he's moved on to injection now!

Has anybody on this forum NOT had a problem with their Amal Carbs. Mine has always had the twin Carb. Mk.1 set up & I have never had a problem. Always set them up myself. As for slide wear, it has never bothered me unless it affects the tickover.
Comments please.

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36 years same set of bodies, second set of slides, 800 rpm steady idle.
Pretty religious wintertime maintenance to pull the slides, clean, check for scoring, and coat with Dri-Slide (graphite lubricant).
Engine always kept in tune and Isolastics adjusted, so vibration has been minimized.

You should get an award Ron. I''d supect your lubing ritual is paying off.

I replaced my slides & bodies in 1982 for the sake of it, still running good. Never had to clean them out, although I bored them out to 32.4mm about 3 years ago. I am sticking to mine, as I have seen people try del-ortos & Mk.11's & never get the jetting right. The bike pulls hard from very low revs, right into the red.

Ta.

The problems of using low quality materials are not solely the fault of Amal. The various manufacturers who used these carbs simply would not pay for a better made product just as in most things cost dictated quality.Bike manufacturers knew the carb may have problems in later life but by then the warranty period would be over.

The design may be simple but it does work well so much so that other makers notable Minkuni copied it in hole or part in later carbs.

As for regular maintaince this was once part of life for all vehicles an as looked on as normal. I like many others spent hours helping my father fix the family car in the 70s and 80s it was just what you did. You can't expect modern levels of reliability form something built in the 70s.

As for cleaning small hard to get at jets an other passages look at the size of the smaller four cylinder machines like 400s with 4 carbs. My friend had a GSXR750wp which if not used for a month would have trouble with jets becoming blocked an i regularly had the whole lot of four carbs spread out his kitchen table (best time to do job was one hour five minutes from taking tank of bike to refitting it) he looked on in horror at the number of tiny parts compared to his trusted Triumph with single Amal he was happy to fix himself.

So Amal are ok an if you get some new Premiers rhey should be much improved life wise.

My own opinion is that modern petrol makes the problems worse & also the quality of the materials that carbs are made of seems inferior. I bought my bike new & my original set of Amals lasted much longer than the next two sets. I have a friend with a Triumph T160 that he bought new in 1975 that still has the original Amals and they still work fine.
From a performance point of view the Amals are very good, it's just the longevity which is annoying.

Ian

Amal Premiers on my MK3. I have about 3000 miles now and they are still perfect. I had to change to a #19 pilot jet, otherwise they perform very well.

The only trouble I've had was my own ignorance when setting them up. Otherwise they have always worked just fine. I had a single Mikuni for a short time but I could never stop it from fouling the right side plug. I switched back to the Amals out of frustration and the problem went away, go figure.

Poor mileage is often associated with worn slides and bores, however it is generally caused by a worn needle and needle block, which often get replaced when the slides get sleeved. Wear in the needle set allows more fuel thru and rich running. Wear in the slide and bore allows more air thru at low throttle opening= leaner running.
Also, really terrific fuel mileage is not always a sign of great carburation or even a good thing. A bike that gets terrific fuel mileage might be one hard uphill on a hot day blast away from a holed piston.
We have one fellow in the club who impressed everyone with his twin Dellorto setup, which he tuned for great fuel mileage with O2 sensors. His bike always required the smallest fillup by far. Then one hot day it holed a piston from lean running did about 5 k damage to itself. All the fuel savings were gone and then some!

If your Commando is getting 45- 50 MPG US or so, I would not be tempted to run it even leaner in anyway, just not worth the risk.

Glen

In 39 years of owning my Norton I have gone through 2 sets of Amals, but I also got long milege out of them 60,000 miles out of the frist ones and 80,000 out of the next set, yes the first set had lots of wear in the slide and the second set had not as much wear, in all the years of running them I never had a blocked polit hole, the bike always ran well even with worn slides, was always a first kick every time and stayed pretty much in tune most of the time, but one thing I always do and that was replace the needles and jets every 2 or 3 years of riding without failure, another words a rebuild kit, but when replacing the jets etc the carbies got pulled down and a good clean, to me its just all part of general maitenance and never over tighten anything on them, because my bike was a every day runner its probly why I never had problems with blocked jets, but now I use my new bike as a everyday runner so only riding the Norton not as much but it still gets ridden and I enjoy it even more when i do.

Ashley

Man........ I must be the only one here that has pretty much had my fill of old Amals.

If the slides ain't rattling, then some previous "mechanic" has tightened something down too tight and messed things up.
Usually the Pilot Screw.
If by chance the carbs do work OK, then you get the pleasure of having your hand smell like gasoline every time you ride the bike and
let's not forget that lovely brown color all over the bodies. Both thanks to the Tickler.

I have a 932 on my BSA 441 right now and have been thinking about replacing it with a Premier. But....... If I do, I'm gonna look into
rubber mounting it (per ludwigs suggestion) as that thumper shakes even more than my Norton.