Amal vs Wassell carburetor

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Amal vs Wassell carburetor

Post by Jeff K »

I was just on Ebay checking Amal carburetors for a up coming project. It seems the the used parts prices have gone up a bit, lot of used junk for a lot of money. I see Amal has their premier version, not sure if that was the better one. I seem to recall that they offer two grades of new carburetors. And then I saw that Wassell is now selling a copy of the Amal. It is almost worth it to purchase a new one then to try and rebuild a worn out one. Any input on the new carburetors?
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Re: Amal vs Wassell carburetor

Post by Momus »

Forget them: might as well try a Minerva wick style.🤔🤣

Whatever it is install a Keihin or Oko PWK, or if you want the absolute duck's nuts in carburetion a Keihin FCR will make you think it's FI.
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Re: Amal vs Wassell carburetor

Post by minetymenace »

Try the search button......
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Re: Amal vs Wassell carburetor

Post by Jeff K »

I did that, " Wassell carburetor" and all I got was a pile of Wassell ignition posts. I was just wondering if anyone had run one before. I have played with other carbs on British bikes and it always turned out to be a pain. Yes you can get them "dialed" in and have fantastic performance. But it can take a very long time and a lot of fretting to get it done. I spent a long time on my Brother's Norton 850 with a brand new Mikuni kit that was set up for the bike. Rubbish! Using a Exhaust gas meter and lots of jetting / slide etc changes. I got it to perform great. but compared to the Amal he had on it, it is very cold blooded and takes a while to warm up. Also with the old tickler on the side, it started better with the amal when cold.
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Re: Amal vs Wassell carburetor

Post by minetymenace »

Try these topics (I've not read them, just copied from the search results for Wassell, maybe the arrowed topic is the place to start), its all here somewhere!

Misfiring while driving. Starts and idles Okay
1971 Trail Blazer.
Mikuni for B44 - too big?
Economy
new carb
Amal Mk. 2 carb
amal or wassel <-------------------
New Concentric MK1s from Wassell
b25ss project on the cheap.
Roadplough wrote:Wassell are very wasselly
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Re: Amal vs Wassell carburetor

Post by Jeff K »

:mrgreen:
A couple of Mikuni posts and a couple on the Wassell going back 6 to 8 years ago. One current post. Seems like unless they have changed their Quality control, people should avoid the Wassell. If the Virus restrictions get lifted for swap meets this fall, I think that I will be going to a few and see what I can find. I have a friend, who like myself is building a 1973 TR5T. He is looking for a Amal 928. I have manifolds and Carburetors in 26mm, 28mm and 30mm for these bikes. Looking for good performance and milage for mostly road use ( small tanks). The T100c did well with the single 26mm. The early TR5T came with a 30mm. Here in Michigan when ran hard in the woods with aggressive dirt tire and large rear sprockets. The TR5T had a tendency to bust the cases at the output shaft bearing behind the counter shaft sprocket. I have one and have seem a few others with this problem, they quickly replaced the 30mm with a 28mm. I was just looking to have a spare 928 on the shelf when I saw how much they were going for on Ebay. This used to be a common size and was used on the BSA B25 and should not be to hard to find a a swap meet
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Re: Amal vs Wassell carburetor

Post by madsundaysurvivor »

Hello,
I prefer original amal for british bike, (dellorto in my others road or racing bikes). But if you have a used body, there are times that they have wear on the bore and even if you put a new slide they do not end up being fine. if you do not have them and you have to buy it I prefer a new premier amal, all the new amal components are very expensive, but some important ones like the new float bowl, with the adjustable float with amal mk2 type float needle
About the pwk and oko, I can tell you that my friends use them but on other bikes, especially two-stroke trials.
in these carburettors it is very important that they are the originals from taiwan, there are very cheap Chinese copies, I have seen € 30, but it is a waste of money, very low quality materials and very poor calibrations. I leave you two links to distinguish copies:
http://www.mid-atlantictrials.com/Copies.html

http://www.sudco.com/genuine_vs_fake_carburetors.html
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Re: Amal vs Wassell carburetor

Post by Jeff K »

Good reading, I was surprised to Sudco's name on the Chinese copies. Used to be that that kind of stuff would get the whole shipment confiscated at the border and destroyed by customs.
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Re: Amal vs Wassell carburetor

Post by grussell »

I have a new 30mm Wassell on my B44VS. Haven't had the bike long but it seems to work fine for the 500 miloes I've done so far. Having said that, sometimes the bugger just won't start. Or will fire but not run. No pattern discernable: can happen hot or cold. But for a useable bike in the 21st C there are better starting solutions than carb tickling. I'm considering a Mikuni VM-30, with choke circuit. Does anyone have experience of this carb on a B44?
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Re: Amal vs Wassell carburetor

Post by minetymenace »

<135 to the forum grussell.

Would you update your profile and let everyone know roughly where you are please?

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Re: Amal vs Wassell carburetor

Post by Jeff K »

Jeff K wrote: Tue Apr 28, 2020 6:34 pm Good reading, I was surprised to Sudco's name on the Chinese copies. Used to be that that kind of stuff would get the whole shipment confiscated at the border and destroyed by customs.
Jeff
I properly set up old Amal with the tickler should start better then a Choke. When you tickle/flood the carb, you get gas raw gas flowing in to the intake. As soon as the piston is moving it has enough to start a cold engine. The Choke needs a vacuum to pull the enriched gas mixture gas mixture into the intake. And that can take a few kicks to do. If you have a separate intake manifold ( longer path), then it makes it worse.
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

I put a 32 mm Mikuni on my B44 with the intake ported to match. Once warm the carb was a dream.. It would idle like a tractor and no flatspots or stutter through out the range to WOT. The problem was cold starts. The enricher circuit would not do it. It took 20-30 kicks to start the mother. Once warm it would start on one light kick. I want back to a 32mm Amal that was worn but the bike when amply tickled would start easily on a kick or two.

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Re: Amal vs Wassell carburetor

Post by Jeff K »

Mr Mike wrote: Fri May 01, 2020 2:08 pm I put a 32 mm Mikuni on my B44 with the intake ported to match. Once warm the carb was a dream.. It would idle like a tractor and no flatspots or stutter through out the range to WOT. The problem was cold starts. The enricher circuit would not do it. It took 20-30 kicks to start the mother. Once warm it would start on one light kick. I want back to a 32mm Amal that was worn but the bike when amply tickled would start easily on a kick or two.

Mr Mike
Same exact problem on a couple of Norton's. Once the Mikuni was dialed in they ran great when warmed up. --- But the were beasts to start and very cold blooded.
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Re: Amal vs Wassell carburetor

Post by Shawn_Mc »

I got a brand new 928 Premier from UnitSingles. It was about 30 bucks more than the parts to completely rebuild the 928 my B25 came with. My old Beezer starts first or second kick every time.

I was originally going to put the Mikuni VM28 on it because Ive got a TON of experience with Mikunis and Keihins. At this point, I'm glad I didn't.
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

I considered drilling out the jet in the enricher circuit but decided against it. Not sure whether that needed to be drilled out or the tiny hole in carb body where the gas enters the air stream. Overall I kike the quality of Mikuni's but they could have put in a traditional choke that throttles the air to enrich the mixture for starting. If I could get it to work on cold starts I'd put it on the 50.

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Re: Amal vs Wassell carburetor

Post by fastharry »

I have fitted several wassell carbs to twins and singles, They also do a premier style version so that you can change the pilot jet, and clean it, no problems from them, I would throw used amal as far into the long grass as possible, the amount of times i have had bikes in with worn carbs, spent hours trying to get them to run right to no avail, NO MORE! Its new carbs or take it away, The only draw back with this style of carb, they do wear out quicker than Mikuni , Keihin or dellorto, One of the main reasons for poor starting with Mikuni's is that they fit the same choke jet in a whole range of carb sizes, I believe it is the same in a 26/28/30/32 maybe a 34mm, and it is too big, so don't go drilling it out what ever you do as was mentioned earlier. Motocarb Uk, do a conversion in house to fit a smaller jet, for about £25 including the jet, You have to prise out the old brass jet in the bottom of the bowl, then drill and tap 4mm and fit the new jet. it makes a massive difference, i did it to 2 T140 bonneville's, and i can now ride down the road with my chokes still on, where as before i could start it but then had to flick them straight off and hold it at 3000 rpm till it warmed up. So yes mikuni's can be made to work, but a bit of time setting them up is needed, The amal /wassell can also need some setting up, mainly the float height, which will make a difference if not set right, As an aside, i also like dellorto's , there choke/cold starting system works well. but they are expensive. Ya pays ya money and takes ya choice!
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Re: Amal vs Wassell carburetor

Post by Ian Hingley »

I've got a Mikuni VM on my B44 Victor.
If it hasn't started from cold within 3 kicks with the choke on, I flick the choke off, turn the idle screw in 1/8 turn and revert to the old way. Do not be tempted to touch the throttle whichever way you choose.
If it does start with the choke on (which it often does) I agree it needs flicking off within a few seconds.
Also agree that once the Mik has run for maybe 30 seconds, you're set for the day. You can sit at the traffic lights with it evenly and reliably ticking over and your hands off the bars, relaxed. Not like the old Amals where you have to have your hand hovering over the twistgrip ready to test your reflexes in case the tickover suddenly dies. Or dies the second you apply a whiff of throttle to accelerate away...

Cheers

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Re: Amal vs Wassell carburetor

Post by Jeff K »

I also noted it was not just the hard starting with the Mikuni, it was also cold blooded. With the old Amal tickle until gas dripped out, one kick even when cold and up and running and you are ready to drive off. With the Mikuni, it was kick, kick kick repeat, and repeat. If it was a cold morning, you could kick ten or fifteen times. then once it was running you had to be very careful and keep the revs up until it warmed up or it would stall. Playing around with settings and jets, I could get it to start a bit better, but then it was too rich once warmed up. Early spring you can see a 40 degree F morning and be 70 degrees by one o clock. And the Amal seem better suited for this weather.
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Re: Amal vs Wassell carburetor

Post by beat »

Mikuni VM is old fashion, and your tecnic to fine tune a carbi is fozillized as well.
none of you friendly gents can tell for sure this VM is to rich ore to lean whilst kickstarting.

so it is NOT a problem of the carbi, - NO, - it is a problem of the reading the A/F Ratio and the jetting :!:

beat, using a TM carb, a Videoband A/F reader and has no problem to start the B50 evan cold ore warm, - kick ore el. starting.
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Re: Amal vs Wassell carburetor

Post by Jeff K »

Hi Beat
I have been using a very old analog A/F meter for years(decades). It is a bigger unit was design for use on cars and trucks. Large fast response scale, long leads to connect to the battery and a unit the slides into the exhaust and is connected to the meter with a long lead. Simple to use. Connect to the battery or 12v power source, use the fine tuning knob to set the meter to present conditions and then insert the probe into the exhaust pipe. It has a large dial and reads fast. As you go from idle and open up the throttle, you can see what effect each jet/circuit has on the A/F ratio. What is surprising is that many times the A/F ratio is the opposite of what you would expect for the problem. I have compared this old meter with several of my computerized units that tap into the OBDI systems in cars and it reads the same as they do, so I know it is accurate. A long gone old triumph Shop Mechanic that I used to knew, used to always say that 90% of carburetor problems are electrical. :grin: Back in the day I believe that he would have been right. But this Norton has a top quality Power Arc ignition system that works flawlessly. The old Amal is crude and sloppy compared to a new Mikuni. But that is part of the reason they work so well on our old bikes. I have found that the Mikuni is too "fine tuned" and can have problems with Temperature, Altitude about sea level and gas quality. Things that the old Amal seems to be more forgiving to. I am not saying that you could not work though the problems with enough time. One other thing that I noticed with the Mikuni, here in the USA we have mandated gas with 10% Ethanol in it. I have noticed that this gas is more corrosive to the Mikuni then to the old Amals. Here in Michigan, we also have a different gas blend for use in winter then Summer.
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

I agree the an AMAL is somewhat outdated compared to Mikuni. However I have always been able to get these bikes to start reasonably easy and run well with AMAL's. I have a box of jets both main and needle and an adjustable float. There is never a problem I can't seem to fix. The Mik on the other hand performs better, especially at idle, once it is warmed up, but I cannot cold start it. I would love to try it on my B50 but until some one can show me how to fix the cold start dilemma, it will remain on the shelf along with the spare jets I bought for it.

I have sold my last B44 and am down to only the B50 which I'll keep even when my riding days are over. I remember reading about the B50 in a cycle magazine in 1971. I was riding a 250 BSA Starfire at the time and wanted a B50 real bad. No money in those Army and college days for anything but the basics

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Re: Amal vs Wassell carburetor

Post by beat »

sure is, evan when kickstarting, the mixture needs to be in a ration from 11.5 to 13.5 let say.
and the drops of fuel in the air needs to be tiny and mixed.

and if you are NOT in this range, - it wont'd start, - ore dies immediately.

so, a good adjusted engine starts easily and runs in idle as soon it is started, - ore it shows you with the A/F reader on wich side the problem is located.
I say located, - NOT solved !!

to solv it, this is then the next step. regardless it is a Amal ore a Mikuni

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Re: Amal vs Wassell carburetor

Post by Momus »

Jeff K wrote: Fri May 01, 2020 2:39 pm
Mr Mike wrote: Fri May 01, 2020 2:08 pm I put a 32 mm Mikuni on my B44 with the intake ported to match. Once warm the carb was a dream.. It would idle like a tractor and no flatspots or stutter through out the range to WOT. The problem was cold starts. The enricher circuit would not do it. It took 20-30 kicks to start the mother. Once warm it would start on one light kick. I want back to a 32mm Amal that was worn but the bike when amply tickled would start easily on a kick or two.

Mr Mike
Same exact problem on a couple of Norton's. Once the Mikuni was dialed in they ran great when warmed up. --- But the were beasts to start and very cold blooded.
Jeff
Change the choke jet to a larger one (or if no removable jet in the well drill larger). Mikuni are fully callibratable. Astounded to hear the starting enrichment mentioned as a problem🤔😑.
Last edited by Momus on Sun May 10, 2020 4:14 am, edited 1 time in total.
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

Momus,
This may be terminology when you use the word "choke". When I use choke it is enriching the circuit be reducing air flow and consequently creating higher vacuum over the fuel bowl to enrich the mixture. Most choked carbs operate this way. The Mik has an "enricher" circuit which allows additional fuel to enter the airflow independently through a separate orifice and you just cut it off with the lever when not needed. While a traditional choke is infinitely variable in reducing the air flow and can be adjusted as the engine warms, it seems to me that the Mik is on or off. I am no Mik expert at all but it seems enlarging the orifice in the enricher cavity might help. Others in this thread have said quite the opposite. So my Mik sets on the shelf in favor of an AMAL, which is a bit more basic, but I can get to work properly. I would love to try the Mik on my B50 but I will not own a bike that does not start easily. I am OK with a couple of kicks to start but no more.

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Re: Amal vs Wassell carburetor

Post by Jeff K »

I have had a lot of Motorcycles, mostly British. I live in Michigan, weather is the stuff stories are made of. It snowed her yesterday, and last week it was in the 70's, so I need a bike that starts and runs well in all temperatures and weather. I have never had a properly tuned and sorted out British bike fail to start or not start in a couple of kick when cold when using the Amal's. Push the tickler down until gas dribbles out and kick-- that is it. Funny thing it is extremely rare to find a British bike around here with the Choke still on it. It was one of the 1st things that the dealers removed when they got the new bikes in. The Dealers used to tell me that they were not needed and cause too many problems if the lever loosened up or the rider did not know how to use it. And I agree the Mikuni Choke does seem to be on or off.
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

Jeff,
I have never needed a choke on an Amal. I tried one and took it off. B50's are notorious for hard starting but I have no problems with my procedure. The MIK on my 441 was useless for cold starting but great once warm. I like the simplicity of the Amals. One time I was out riding a 441 and the bike started to gag,,,it was flooding, I pulled over dropped the bowl off and the float had a hole in it and was full of gas. I just put it back together, turned on the gas till it flooded then shut off the gas. I'd run it about 1/4 mile and turn the gas back on till it faltered and then cut it off. Made it all the way home that way. Try that roadside fix on a modern carb!

I would try the Mik on the B50 if I knew exactly what to do...but opinions are mixed.

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Re: Amal vs Wassell carburetor

Post by Momus »

Mr Mike wrote: Sat May 09, 2020 4:52 pm Momus,
This may be terminology when you use the word "choke". When I use choke it is enriching the circuit be reducing air flow and consequently creating higher vacuum over the fuel bowl to enrich the mixture. Most choked carbs operate this way. The Mik has an "enricher" circuit which allows additional fuel to enter the airflow independently through a separate orifice and you just cut it off with the lever when not needed. While a traditional choke is infinitely variable in reducing the air flow and can be adjusted as the engine warms, it seems to me that the Mik is on or off. I am no Mik expert at all but it seems enlarging the orifice in the enricher cavity might help. Others in this thread have said quite the opposite. So my Mik sets on the shelf in favor of an AMAL, which is a bit more basic, but I can get to work properly. I would love to try the Mik on my B50 but I will not own a bike that does not start easily. I am OK with a couple of kicks to start but no more.

Mr Mike
Agree with the terminology. Mikuni and Keihin use enrichment circuits on most of their offerings. Many Mikunis had a removable choke jet. Whoever is supplying or specifying the kits or conversions has not done their job if they are lean starting.
As for those who ride their bike while manipulating the choke haha 🤔🤡. You warm the engine properly then ride: not make silly claims about the sufficiency of otherwise satisfactory carbs.
Mike you may know; has anyone here fitted a Keihin FCR to a B50?
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Re: Amal vs Wassell carburetor

Post by Jeff K »

Using a A/F exhaust gage and spark plug color checks. I can get both the Amal And the Mik jetted properly so the bikes run great when they are warmed up. But the Amal will start right up and I can drive off, where the Mik will be hard starting and stumble unless you keep the revs up until the motor is warmed up. If I re-jet so the Mik is not so cold blooded, then it is running rich once the motor does warm up. And this is with some expensive kits that are set up for the bike. I just find that the Amal is more forgiving. I am not saying that if you spend a lot of time, that you could not get the Mik to run better. I also find that on days with big temperature changes the Amal also is better. A cold damp morning and then a hot afternoon would cause this also.
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

I agree with Jeff. My inexperience with a Mik is likely part of the problem. I first bought the Mik and made the necessary changes to mount it. I bought some extra jets and I was quickly able to get my 441 running great. I was impressed by it's strong performance and unfaltering idle. Then I went to work on cold starts and never figured it out. I am tempted to drill out the orifice in the enricher circuit (which is not removable) but there is no fix for that if it doesn't work. So if someone knows of a website that might explain how to approach this problem please post it.

On another thought, most of these small two stroke motors we have on weed hackers and such have a bulb that floods the carb for starting....not unlike our ancient AMALs. Maybe we need to give a little more credit to AMAL.

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Re: Amal vs Wassell carburetor

Post by fastharry »

Mr Mike i have already explained several post above how to fix the Enrichner circuit on a Mikuni! And yet the last 6 posts have chosen to completely ignore it, This site gets more like facebook every day! Folks just leap in with there comments without reading prior feedback! I will spell it out again! You do not need to drill out the choke/enrichner jet on a Mikuni! You need to make it smaller. ignore me if you like But Call Moto Carb 0151 924 5383 and he will put you straight, he only deals in Mikuni's. If you live outside the Uk its still worth your time contacting Steve, Or forget it. and piss your fuel out all over the floor when you want to run your bike. Gretta Would Slap you so hard!
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Re: Amal vs Wassell carburetor

Post by minetymenace »

fastharry wrote:This site gets more like facebook every day!
Complain to the moderator, he will do something I promise.
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Re: Amal vs Wassell carburetor

Post by Jeff K »

fastharry wrote: Tue May 12, 2020 7:20 pm Mr Mike i have already explained several post above how to fix the Enrichner circuit on a Mikuni! And yet the last 6 posts have chosen to completely ignore it, This site gets more like facebook every day! Folks just leap in with there comments without reading prior feedback! I will spell it out again! You do not need to drill out the choke/enrichner jet on a Mikuni! You need to make it smaller. ignore me if you like But Call Moto Carb 0151 924 5383 and he will put you straight, he only deals in Mikuni's. If you live outside the Uk its still worth your time contacting Steve, Or forget it. and piss your fuel out all over the floor when you want to run your bike. Gretta Would Slap you so hard!
FastHarry, I did read your post. And it basically said what we were saying. You can get a Mik working with a lot fretting on it(compared to the old Amal). I can purchase a new Amal properly jetting and ready to run out of the box. I have purchased Mikuni's that were sold as ready to run and were sold to be ready to run of a specific motorcycle. And they were not even close. I do not feel that after purchasing a new carburetor that I should have to send it out or have to machine it my self to get it to work. I do not have that advantage of having someone to send it to to have it fixed. Shipping to the UK, the $25 pounds to fix it and shipping back, I would have the cost of a new AMAL. And with this Virus problem I already have one shipment from the UK that is 1 month overdue. The Miks have a couple of problems right out of the box, the hard starting and the taking longer to warm up. Once warmed up and dialed in they are great and will run cleaner then the old Amal. I also find them to be more sensitive to gas quality and temperature changes. Thanks to "Greta's" friends, we have gas that has 10% ethanol in it and very corrosive. From the few new Mikuni's that I have recently installed, I have found signs of slide and bore corrosion from the Ethanol in less then a weeks running( white coating). We also now have gas where the is blend different for different times of the year and this stuff goes flat very fast and due to the Ethanol likes to suck moisture out of the air where it will build up in the float bowl. Add to that where I live temperature changes are everyday. Last night it was well below freezing and in two days they are calling for it to be in the 80's F. The last couple of Bikes that I worked on where the owners had to have a Mikuni on them were a pain. I special ordered them and they came all set up with proper jetting and adapters etc. :roll: Right, many hours, jets and slides later and More extra parts on the shelf, I did get them running good. But that can take days of running and testing under different condition. Mikuni are also very sensitive to Altitude and all seem to come set up not for my area.
The Mikuni is a great Carburetor and years ago I used them a lot on Dirt bikes etc, I used to have a account with SUDCO at the time. But they are a very finely tuned and sensitive carburetor. Once you have them dialed in great! The Amal on the other hand is a old designed, crude, and "sloppy" . But this is exactly what makes it so easy to set up and run. I can pull a old Amal off the shelf look up the proper slide, jets and settings etc, and install them. Slap it on a bike and it starts and runs. They used to get a bad rap about stalling at Idle, I found that most of the time that that was a ignition problem. Worn out, or sticking advance or points rubbing block. Norton had so many problems that they change points styles on the late 750. Some times it would be due to the worn Amal slide/bore. I used to be able to purchase Molykote Spray through Dow. It is a spray on dry film coating of Molybdenum disulfide. I would use it on the slides and never had any wear problems. I also would coat transmission gears with it. On one 750 Norton that was rode hard, a few years later when I pulled the gearbox down to replace a broken shaft, the Moly coat was still on the gears and doing it's job. Not cheap stuff, expect to pay over $50 a spray can, it is used a lot by the military and in aircraft repair.
I am happy that you have some one near by who can do this for you and I am happy that you have them dialed in and are able to enjoy your motorcycles.
Jeff
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Re: Amal vs Wassell carburetor

Post by Momus »

fastharry wrote: Tue May 12, 2020 7:20 pm Mr Mike i have already explained several post above how to fix the Enrichner circuit on a Mikuni! And yet the last 6 posts have chosen to completely ignore it, This site gets more like facebook every day! Folks just leap in with there comments without reading prior feedback! I will spell it out again! You do not need to drill out the choke/enrichner jet on a Mikuni! You need to make it smaller. ignore me if you like But Call Moto Carb 0151 924 5383 and he will put you straight, he only deals in Mikuni's. If you live outside the Uk its still worth your time contacting Steve, Or forget it. and piss your fuel out all over the floor when you want to run your bike. Gretta Would Slap you so hard!
What are you smoking mate? <201

If the engine is diagnosed correctly as running so lean on the enrichment circuit to prevent starting and steady cold running you enlarge the jet at the bottom of the fuel bowl.
The enrichment circuit It is a crude carburettor within a carburettor; lifting the knob or deploying the lever opens an air passage and a fuel well. If you are lean on the main circuit at full power do you fit a smaller main jet?
If you love it, lube it.
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Re: Amal vs Wassell carburetor

Post by fastharry »

So far i have not seen a Diagnosis that points to the mikuni enrichment circuit being lean or rich at cold start, as i think jeff said, he improved the cold starting by by changing the jetting (but no specifics) i would guess you upped the pilot and left the choke lever off until it improved cold starting? and then it would be to rich at the bottom when its warmed up. One chap asked if anyone had got mikuni's to work, well i have on 3 bikes. and each one i fitted a smaller jet into the float bowl, Jeff K, You don't have to send it away to be done if you have a small drill press/stand , a vice , 3mm drill and a 4 mm tap, The guy at Motocarb eases out the the pressed in brass jet then drill and taps the bowl (from the inside) to 4mm then screws in a much smaller jet #40, (somecarbs have changeable choke/airjets, the VM30/32 do's not) I do it from the outside of the bowl because i find it easier to use the flat surface of the bowl to get an accurate datum for drilling. if you turn your bowl upside down you will see a 8mm or so piece of casting sticking out directly under the brass jet thats in the bottom of the bowl. Sometimes the casting is very slightly uneven so i dress it with a file to get it flat. i drill it 3mm then then knock out the brass jet from its underside, i then tap the hole to 4mm making sure to thread past the fuel feed hole so the the new jet does not block it off, i then plug the bottom of the bowl with a short 4mm cap head and fibre washer. Takes about 40 mins, and £4 for a jet. Hope this helps some one that has an idle Mikuni sitting on the shelf. Or email sales@motocarb.co.uk and get it from a mikuni specialist.
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Re: Amal vs Wassell carburetor

Post by Ian Hingley »

This is a strange thread.

I've been around this forum a few years now. Only 2 or 3 years ago there was a real groundswell of opinion against Amals with their ancient design, limited no. of adjustments you can make, poor cold starting, poor hot starting, poor tickover, poor fuel economy, poor build quality, poor quality control, pure inconsistency.

People were switching to Mikunis as something working to the same principles, but with an up to date design and modern manufacturing standards bringing consistent results. Remember HPbyStan's comments on Amals?

In the space of only a few weeks there's been a complete about turn. Amals were the best all along and these new-fangled imposters just can't cut the mustard. Seems everyone's B50 or B44 now starts first time every time hot or cold even if the bike's been stood outside for 6 months and the fuel's all turned to water.

Still, might work in my favour. I've one Mikuni, on my Victor, but a whole draw full of Amal concentrics. Maybe I should sell them for big bucks on eBay...

Cheers

Ian IHOSMILE
66 BSA Victor Enduro, 72 BSA Lightning, 62 BSA B40 trials, 2015 Truimph Street Twin, 89 H*nda Bros 650, 2000 Aprilia Moto 6.5 Starck
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Re: Amal vs Wassell carburetor

Post by Jeff K »

Ian,
I started this thread. I will be 65 in a couple of months and I have been working on bikes since I was old enough to throw a leg over Sears 5hp minibike :thumb . I worked on Japanese motorcycles decades ago and I worked at K*wasak*/S*zuki dealership as a mechanic. I am well versed in Mikuni's. But I switched over to British Motorcycles at the start of the 70's and I must be lucky because I have not had "issues" with the Amal's. I still occasionally work on or restore a bike or two. My problem is that I still have a couple of shelves full of Amal's and their spares. I do not wish to start stocking another brand and their parts. That is why I was asking about the New Amal's and their Wassell clones. Their are a lot of Carburetors out there and there are a lot of people who swear by their favorite brand, Mikuni, Keihn, PWK, Dellorto and their many clones. I like the fact that I can look at a chart, piece together or order a Amal, put it on a bike and it will start up and run. I have recently installed some expensive Mikuni kits that were all set up and ready to run for certain bikes and that has yet to be the case. I have a full machine and welding shop so machining a new Carburetor can be done. I just have a problem needing to do it when a stock Amal works out of the box. I have recently gotten rid of 19 of the old bikes and all of my Monoblocs and parts. I did keep 12 bikes, I kept the 71 or newer models and only my old 1939 M20. I did keep two 71 250 Triumphs and one BSA 250 so I am still BSA Single rider and I have a 1973 & a 1974 TR5T. :grin: A handful of the bikes need nothing and run. The rest I will be restoring as I find time. That is why I was asking about the new Amal vs the Wassell clones. I have piles of bodies, jets, slides etc for Amal's and I do not wish to have to start stocking another brand's parts. I know Mikunis and they are a great Carburetor and I am happy that people are using them and are happy with them. I am not racing or riding in competition anymore so the basic Amal still suits my needs.
I was just shocked at what people listing used Amal's on Ebay for.
Thanks to everyone who has responded. If your response did not help me, then I am sure that it did help out another member. That is what is so nice about this forum. :thumb
Jeff
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Re: Amal vs Wassell carburetor

Post by fastharry »

As i said at the top Jeff, i have had no major problems with the Wassell Premier if thats the style of carb you prefer, I have 6 on the shelf. Good luck with your projects, Im a year behind you, still racing flattrack, and like you, have a stack of projects, The next 2 i have just started on are Trackmaster Triumph and Bsa 750's! Long nights and cold beers! :thumb
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Re: Amal vs Wassell carburetor

Post by Jeff K »

fastharry wrote: Wed May 13, 2020 10:33 pm As i said at the top Jeff, i have had no major problems with the Wassell Premier if thats the style of carb you prefer, I have 6 on the shelf. Good luck with your projects, Im a year behind you, still racing flattrack, and like you, have a stack of projects, The next 2 i have just started on are Trackmaster Triumph and Bsa 750's! Long nights and cold beers! :thumb
The older I get, The more I can appreciate the slow and easy. :mrgreen: I am getting everything lined up for a 1973 TR5T build and I am helping a friend who is also building a 1973 TR5T. At this point in life I like going into the shop, turning on the radio, if it's early, a hot coffee. If it is later then it is a cold beer. It is nice to be able to work without having to answer the phone or getting interrupted. :ban
Jeff
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Re: Amal vs Wassell carburetor

Post by Mr Mike »

Fella's, we all have to get along. For most of us this is a hobby. I started this fuss when I sort of hi jacked the thread wanting to know is what must be done to the enricher circuit to get my B50 to start cold. Many others have had similar experiences. I have heard to drill out the non removeable jet, I have heard to replace it with a smaller #40 threaded jet. I have looked at Mikuni u-tube videos and emailed a guy in New Zealand who specializes in Mikuni's. There does not seem to be a common answer. When I sold all my bikes, keeping only the B50. I kept the Mikuni and the adapter to try it on the B50...it was a curiosity thing as it had run so well (except cold starts) on my last 441.

BTW for Fast Harry, what is the diameter of the hole in a #40 jet. I could remove the existing jet, machine a plug, face it off at the right height and drill it to the right diameter if I knew wat that was. My brother is a retired tool and die maker and has a couple of lathes and a milling machine in his shop. Meanwhile, I am not grounded as my Amal is properly tuned for the B50.

Meanwhile, as a long retired engineer, I'm with Jeff...a hot cup of coffee in a thermal mug in the morning and an ice cold beer at 5:00.

Cheers,
Mr Mike
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Re: Amal vs Wassell carburetor

Post by fastharry »

Mike. I don't have the size of the hole. I asked Motocarb, and they say its based on the flow rate so no particular size is measured, I can tell you they are on sale on ebay USA for $4.50. Item number is for a #60 but i think he carries them all, item number 161059317156, Mikuni part number VM17/1002 #40 if you have a local mikuni agent, jetsrus.com has them at twice the price though, Sudco should have them, Hardly worth switching your lathe on for 4 bucks?
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