Availability of notched spray tube for new Amal carbs

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Corona850

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I sent the following question to Amal/Burlen about the spray tubes in Premier Mk 1 carbs:

"I have a question about the following product: - Premier Concentric for Norton Commando 850. The original Amals for these bikes had a special, notched spray tube (928/107) and matching needle with four rings (928/104). Is this configuration available for new 932 Premier Concectrics? I ask because they do not seem to be listed on your website."

And I received the followng answer:

"The only configuration difference between the standard and Premier carburetters for Commandos is the design of the Pilot Jet. Although there are differences in materials e.g., Stay-up floats, alloy needle valves, hard anodised slides, the spray tube and needle used are unchanged."

Which, I don't think answered my question> So, does anyone on this site know if the notched spray-tubes and 4-ring needles are available? I cannot find item 928/107 listed on Amal's site, although the needle is if searched for by part number.

Perhaps this has been discussed before, in which case please refer me to that post/thread. And, yes, I did search for it before posting the question.
 
I have answers for you but I will help you only if you change that avatar.

Otherwise I'm sure L.A.B. will chime in soon.
 
Corona850 said:
And I received the followng answer:

"The only configuration difference between the standard and Premier carburetters for Commandos is the design of the Pilot Jet. Although there are differences in materials e.g., Stay-up floats, alloy needle valves, hard anodised slides, the spray tube and needle used are unchanged."

Which, I don't think answered my question
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Burlen's answer is clearly less than satisfactory. If they are not supplying Premier 850 carbs to standard specification then I think we need to know why.
 
I know that these are available from Old Brits. I bought a set for some 932's that the DPO bought to replace the original ones on my Commando. The new carbs he bought didn't have the 850 Amal mods. I haven't put them in yet because I was able to salvage the original ones that came with in a box with the bike. According to Old Brits the change to the notched spray tubes is easy, just tap out the old ones and tap in the new ones. I don't know how this applies to the Premiers. You could send Fred & Ella an email and ask. They are very helpful.

Dave
 
pete.v said:
I have answers for you but I will help you only if you change that avatar.
Click to expand...

Bald, bug-eyed fellas unnerve ya, do they? Where's the acceptance of people for who they? There's some poor geezer in this world actually looks like that!
Anyway ... changed ... but even scarier, I think. :lol:
So, gimme your answers ...

LAB - Thanks - Yeah, I think it would be good to know what is being provided. How are the Amals that are sold on this site configured?
 
drp said:
I know that these are available from Old Brits.
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Thanks. I see that they're back ordered, though (i.e. spray tubes).

drp said:
According to Old Brits the change to the notched spray tubes is easy, just tap out the old ones and tap in the new ones. I don't know how this applies to the Premiers.
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Yes. I understand warming the bodies helps, too. But, if I spend $180 or so per carb on new ones, I don't really want to have to start changing bits and pieces straight away. It might come to that, in which case I'll just modify my existing carbs instead of replacing.

I'm looking at all options right now. Premier Concentrics look appealing in concept and price, but they have to work, too.
 
Not unusual for original parts to be superseded by replacement parts. It happens. Not Amals fault.
 
Hi
I bought a set of premier amals for my mk3 with stepped tube and the longer needles, just ring them and they will sort it for you. I accept the online site does not list them but they can supply no problem.
JohnT
 
Y'know, I was going to ask you about that avatar. It was scary! This one's much better in my opinion. I can picture some 60s Brit hooligan...
 
Not unusual for original parts to be superseded by replacement parts. It happens. Not Amals fault.
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In this case if the stepped tube is no longer available then it is Amal's fault as they are the OEM, as it is they probably are still available but the answer did not answer the question asked.
 
Amal use a different part number for the Norton 850 spec carb if you order 932/35 & 932/36 not the stock 932/300 / 932/301 they are supplied with the
correct needle and notched spray tubes

if they are out of stock of needles and spray tubes and you do not want to wait 2-3 weeks plus for delivery
you can source these parts from a wassell carb stockist ( i have used Wassell needles 9/104 and tubes 9/107 without problems )
 
Thanks for your input, guys.

I was going to re-send my question to Burlen/Amal, but they beat me to it and sent the following follow-up reply today:

"All 850 Commando carburetters are built using the original Amal build sheets and are fitted with the 928/107 spray tube and the 928/104 needle. This applies to standard and Premier carburetters. All the bodies have the correct machined flanges and throttle stop bosses and the 932/33 and 932/34 specification carburetters are fitted with the 622/056 float chamber which uses 0.125” needle valve seating rather than the standard 0.100” seating. Again this applies to standard and Premier carburetters and is as originally specified."

It was sent by Phil Beresford, Technical Sales Co-ordinator .

So, all is well! I can move ahead with Amal Premier carbs.
 
I was hoping I could add a question on this post regarding the notched spray tube and needle combo that Commando's use, could some one explain to me why these parts were necessary for use in the Norton carbs? What did the non-notched tube do that the Commando didn't like? Would Commando type set up be something to consider if installing 32mm Amals on a big bore Triumph with a Norton stroke crank of 89mm, this engine would approximate bore and stroke of a Commando...I know the Norton has a better head design then the Triumph but don't know why the Norton wanted a different carb set up. Thanks, Mark
 
marksterrtt said:
I was hoping I could add a question on this post regarding the notched spray tube and needle combo that Commando's use, could some one explain to me why these parts were necessary for use in the Norton carbs? .... Thanks, Mark
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I have a lengthy blurb on this somewhere, but can't find it right now. So, I did a forum search and came up with the following succinct answer from 2005. It about sums it up, I think. It was an 850 problem that Amal fixed with the spray tube and needle combination.

bruce chessell said:
The 74 and 75 850's had split spray tubes. They also need the longer needles ( 4 marks on the top ) to match up. There were flat spot problems on some of the early 73 850's and the split spray tube helped atomize the fuel better and overcome it. The 73 750's and combats with 32 mm carbs used the standard needle ( 2 groove ) and round spray tubes.
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I know there are people on this forum who can elaborate widely on this topic.
 
Interesting, thanks Corona850, makes me wonder why, if it atomizes better then shouldn't that be better for any of the big twins?

Glad you got your question answered, if I go back to Concentrics, I think those Premiers would be the choice...

Couldn't help notice you're from Corona, until recently my late brother spent the last 35 or so years there, got to go down and help sister-in-law clear out some aircraft and motorcycles & parts, of course I've waited til it's good and hot...Mark
 
I'd always understood that the cut-away spray tube related to the 'black box' induction system but it seems to have been fitted from the launch of the first 850 Mk1s which used the paper filters. 'Motor Cycle' of 10/3/73 stated the following :-

"...Good low-speed torque is the object, also of detail changes in the Amal Concentric carburettors. As on the 750cc engine, choke size is 32mm, but for the eight-fifty, there are differences in jetting, spray-tube design and needle profile..."

I run mine with full spray-tubes, a 750 air filter and non-balanced exhausts. I can't say that I've noticed flat spots or a lack of torque. It's all a bit puzzling but there must have been a reason...noise tests ?
 
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