Last year I had the 276 from my M20 overhauled. Correct spec just worn out. It came back nicely refurbished, but I found the bike difficult to start and gutless on the road. Lifting the needle to the 4th slot made some difference but it was still running too lean. I noticed that the replacement needle jet was new and had the code 106 engraved on it by hand. I replaced the original standard 1065 jet which had been returned with the carb and now everything is fine. Starts easily and pulls like a train again. I can’t believe that .0005 difference on the jet could be so great that raising the needle by two grooves wouldn’t compensate for it, so my guess is that the replacement was dud. It’s that old thing again - take nothing for granted.

The needle jet does make quite a difference and as far as I can extrapolate from all the documentation that I have been able to find, 106.5 was in fact the standard size during the period that the 276 was being supplied as an original equipment fitment. Burlen-Amal seem to have "forgotten" this, or there may have been a post-war after-market change which they now work to.

All the Norton WD16H Amal Spec cards that I have examined at the VMCC state "Standard Needle Jet ?" and are then completed "Yes" and this also applies to the couple of M20 cards that I have seen. The well-known Amal 1940 - 1954 "Settings and Spare Parts List" lists "Std." for most machines and exceptions are listed. Amongst these exceptions, I can see .105, .106, .107, .108 and .109. The .105 seems to be restricted to 2-strokes.

It cannot therefore have been the case that "Std." was a .106" or .107" It seems likely that it was the .106.5" item. The records show a change to stainless steel needle jets in early 1945 and I have one of these also hand-engraved showing 106.5

The M20 carb supplied by Burlens has a 107 jet fitted, not a 106....Bizarrely the 100cc bigger M21 uses the 106 size....Due to the small size of the hole in the jets a tiny discrepancy will make some difference bearing in mind that cross sectional area increases disproportionately to diameter...It may well be Burlens are working from post war figures...There are various pattern jets/needles out there and I know some of those are used in refurbishments. The tolerances applied are basically unknown for those....Personally I always source these parts from Burlens.....
After numerous problems with refurbished carbs I gave up in the end and opted for the very expensive new pre monobloc carbs from Burlens...I've had no problems with those to date and have recently replaced the one on my M20 after 15-20 years service....Ian

email (option): ian@wright52.plus.com

So are Burlen fitting a 107 as a compromise as they don't seem to make the 1065, which is established as the "standard"? Ron

email (option): ronpier@talk21.com

I'm certainly not privileged to their technical information, Ron but the fitment of a .107 as "standard" seems to contradict the implication in all the 1930s - Early 1950s Amal documentation that I've been able to find.

Did Amal drop the .5 steps at some point after large scale production ceased ? I don't believe that Grosvenor Works ever made 276 parts ?

I have not however been able to find a "period" document that definitively states ".106.5 is Standard"

I don’t know how I know that .1065 is ‘standard’, it’s just something that’s always been in my mind. But now I’ve looked at the AMAL settings chart for 1940 and it shows the WD M20 as ‘standard’. As were the majority of other bikes. Where carbs have other sizes they are stated, there are many at 106, 105, 107 etc, but I couldn’t find a 1065. So, none of the specifically stated sizes were ‘standard’ at that time.

OK standard was a 106, and as most bikes used them they never ever stamped them, they only stamped 105, 107, 108 and 109. My Amal books all show a 106 fitted to M20. Grosvenor Works did sell the 276 and 289 parts including the needle jet as I used to purchasse off them till they closed.I suggest your needle jet marked by hand is from India as I had a guy here in Australia try to sell me a heap of parts that he believed were new old spares left By the British forces in India. I got him to send me 2 x throttle needle, 2 x 106 needle jet and a couple of main jets to check. They were all completely wrong the throttle needles were too short and wrong thickness and the 2 needle jets when measured one was a 104 and the other a 105. They were both hand written as 106. He got hostile when I knocked him back as he claimed he paid good money for them out of India. I have never purchased any hand written needle jets as all reputable suppliers stamp them. For the past twenty years or more all 106 needle jets have been stamped, If it is unstamped you know it original. Burlen do sell a 1065 needle jet but I have never used one. Amal books show 106 as on 2 strokes as Rik mentioned but for 4 strokes always standard.

That's good to know John. So when they show a 106 instead of standard, it's for a 2 stroke! Ron

email (option): ronpier@talk21.com

The postwar BSA M20/21 parts lists show both the M20 and M21 as having a 1065 jet fitted as standard when 276 equipped...I've checked this jet on Burlens website and they do supply it...As other listings show the 106 as 'standard' I guess there's a choice and some fine tuning involved...Though the question may be why the spec. was changed?...Ian

email (option): ian@wright52.plus.com

John, I'm really keen to understand this, but why does the 1936 Amal list show (amongst others) that a couple of small side-valve BSAs used a .106 needle jet if this was the "standard" that went unremarked on most other machines ?

I cannot explain why the two bikes on the 1936 list a 106, very strange.Could it be a mistake like happens with specifications in some Roy Bacons publications. To answer Ians query all of the Amal literature that I have shows M20 having a 106 needle jet from 1937 to 1939 and again 1940 to 1945 as standard(106). Obviously BSA specified 1065 but they probably did not bother as 1/2 a thou did not make virtually any difference whereas one thou will make a difference. For instance most Triumphs use a 107. I have purchased probaby 5 M20 carbureters over the years and they always had a 106 needle jet. I stated earlier that they do carry them but I am yet to see a 1065 fitted to them? The reason they never stamped the needle jet with 106 is that most motorcycles used that size needle jet so would have cut down on production costs of stamping them. The unstamped ones were originally steel and later brass.

It's not unknown for BSA publications (and others) to have mistakes...In this case, who knows?....Anyway, the spec. I quoted is from a post war parts list...It's clear that a 106 is the standard fitment for the WD models we discuss here...Ian

email (option): ian@wright52.plus.com

I've got several of these documents from the AMAL archive. Every one says "yes" to Standard Needle Jet. But no size given. When I feel in the mood, I'll go through the Amal spec sheets and see if there is a 1065 listed for any bike. Ron

email (option): ronpier@talk21.com

I see your example shows a mid cable adjuster fitted...Do you have an M20 card and if so does that show an adjuster fitted?..I'd be interested to know...I generally don't fit them due to the fact they allow water to get into the cable...When I do, I reverse the outer and put the adjuster under the tank....Ian

email (option): ian@wright52.plus.com

1941? BSA B30? Middle Stone Shade????

Rob

email (option): robmiller11(a)yahoo.co.uk

I don't have the WM20 card Ian. But there doesn't appear to be any midway adjusters in period photos. But it's not a bad idea to do it the way you suggest to give a bit more adjustment than what is usually afforded.

To my knowledge, the WB30 is the only war time bike that calls for the throttle and air lever midway adjusters in the parts list (with measurements) Mine are fitted as per the instructions.

The only other (WD) midway adjuster that I've encountered is the Clutch cable on the Velo's! That one is supposed to be positioned under the tank which literally means removing the tank to adjust it. I've got mine exposed near the handlebar.:smirk: Ron

email (option): ronpier@talk21.com

Thanks Ron...Ian

email (option): ian@wright52.plus.com

email (option): ronpier@talk21.com

Middle Stone sounds like one of the desert colours, didn't you buy an air filter from the Middle East recently in a similar colour?

Could this sheet be for export models or considering the rarity of the WB30, potential export models, after all several M20 contracts from the mid war period were originally going to be WB30s and were then altered to WM20s.

What other sheets do you have which could answer these questions?

Rob

email (option): robmiller11(a)yahoo.co.uk

Hi Rob. Here is my Burgess filter as it arrived.(Khaki Green?)

I've also got Amal documents for the Matchless WOG3 and Velocette MDD. Both mention:-

"All bright parts to be dull chrome plated with mixing chamber and float chamber in new finish and lacquered"

Could this new or another finish have been stone instead of silver? I'm sure I've seen it!

I'm convinced that Amal would have had no say in the colour of the actual machines? Ron

email (option): ronpier@talk21.com

No.62 Stone is mentioned in this early G3 spares list as the alternative to KG No.3, I had assumed that meant desert colour?

Rob

email (option): robmiller11(a)yahoo.co.uk

Yes I agree Rob, So at some point Amal were painting and lacquering their carbs to match "Service Colours" The Matchless and Velo cards don't specify a colour, just "the new colour" The MDD's were specified for the French government.( although they were canceled when Paris fell)

I have G3 parts lists for four contracts and they list Carbs and most individual parts in DF. (Dull Chrome) Ron

email (option): ronpier@talk21.com

Does it say just the Burgess air filter is painted desert colour?, air filters weren't a standard fitting for BSAs or any other makes in the NW Europe theatre at this time so that would sort of make sense, WB30s were never a standard issue machine, the GPO and Admiralty may have ended up with some small odd batches but only to stop them getting the good stuff needed by the Army (The WM20). And Malta is where they seem to turn up which is nearer Africa than anywhere else?

Rob

email (option): robmiller11(a)yahoo.co.uk

Rob I need to get a better copy of that B30 Amal card without the bottom lines missing. Ron

email (option): ronpier@talk21.com

I took a really crappy photo of the card for India Office / High Commissioner for India M20 which I'm not sure would reproduce here. Taken at the same time as the WB30 card that I chopped the bottom off...In my defence, either Jan or Rob had the camera stand set up to photograph factory record ledgers.

The India Office M20 card states "Special Finish No.62 Middle Stone Shade" I suspect that the Burgess filter-equipped WB30 was also intended for India or at least Indian Army in MEF.

The WD16H cards all simply state "Mixing chamber and float chamber lacquered". Presumably this was the silver shade, or was it simply a varnish / lacquer over the bright cast finish ?

I have been looking at the VAOS MT12 Chilwell catalogue March 1944 and there doesn't seem to be any mention of sizes in there apart from the 76A/2N which states AM/6/065 Needle jet 1075 but the drawing shows this pointiung to the outer brass jet holder?, but there are some diffent part numbers for the needles AM/4/065, AM/5/065 and AM/6/065 but thay appears to match the different size carbs 274, 275 and 276.

So not much use really.
Rob

email (option): robmiller11(a)yahoo.co.uk

We went all through this a couple of years ago.
At least for the 16H 106.5 was the standard. Burlens confirmed this and I subsequently bought a 106.5 from them at Stafford which they had started making again [It wasn't in their catalogue].
As prior to this they weren't available I'd fitted a 106 raised the needle and gone up two sizes on the main to compensate. It ran fine at that except for lumpy running just off and at idle, which could just as well be the worn jet block/slide.
Recently I bought the correct KLG and the engine now is smooth everywhere. Well smooth running anyway... I'd tried loads of different plugs, the only one with the correct heat range being a Bosch, not presently available. Everything else either loaded up or overheated. I still haven't installed the 106.5.....
As an aside Norton habitually used half sizes for the 276, on lots of different engines. No other manufacturer seems to have made a habit of this. As an educated guess I'd say Amal tested the 276 in conjunction with Norton. Their proximity and the time frame of the 16H makes this likely.

I have never seen a .1065 and never seen one fitted to a Norton. My original Amal War years book and later Amal books do not mention a 1065 being fitted to any Norton?

In March 1945, Amal began fitting stainless steel needles and needle jets to the 276AE/1BE supplied for Nortons.

I assume that this might be one of those ? Did the hardness of the steel preclude stamping so engraving was used instead ?

https://imgbb.com/gVBY4CJ