ET: Engine (Twin) Mk2 Amals

Bill Thomas

Well Known and Active Forum User
VOC Member
Thanks Robin, I have seen other people with this setting,
But my bike is still L/ning spec, 25 pilot, needle 106, slide 3, main 220. My Twin needs 35 starter jet,
The Comet, Which is Flash spec likes 50 starter jet.
But other settings the same as above.

We did some work on a Bike a while ago, Which would hardly run with 3.1/2 slide !!, And had to go 3.
On mine, Last year, I made the cutaway, slightly bigger than 3, And got a really bad misfire, Had to trim a bit off the bottom, To make it richer again.
Cheers Bill.
 

hrdsuper90

Well Known and Active Forum User
VOC Member
Hi Bill, those start jets seem large to me, I used 30s with race pipes. One thing to check (Bob Newby suggestion) behind the ram tubes sits a little alloy spacer known as an air correction device but not listed on Amal sheets. Bob found out the hard way with it missing, as did I with new carbs. Back to those Gardners ?! Cheers Chris C.
 

Bill Thomas

Well Known and Active Forum User
VOC Member
Hello Chris, Hope you are keeping well.
Yes I found out about that jet with the first one I bought for the 2015 Comet, It was set up for methanol !.
I had to make one.
I will try 30s on the L/ning, Strange the Comet is OK with 50.
Last time I rode the L/ning, I tried what T.T. said and turned it over a few times holding the valve lifter,
To Prime it, And it started super from cold on 35 starter jets, Not been run for a month or two.
Lucky, I bought an almost new 30mm Mk2 for £20 at Netly Auto fair this year, For the New Comet,
Just the choke missing, But bought the missing bits from Surry Cycles, Who had a stand there.
Roll on the Spring, Cheers Bill.
 

vibrac

Well Known and Active Forum User
VOC Member
I have had it up to here with those Amal concentrics life IMHO is too short to spend time on them any more. they were bad enough when made by the original company.
The origina pre 55 carbs are OK if not worn Monoblocks are acceptable if the Ethanol is kept at bay and even Italian stuff
Best quality are racing carbs doctored for tickover on the road or Jap carbs. On the other hand if you are interested in puzzles that change as you try and solve them you can't do better than an old concentric.
 

Ducdude

Well Known and Active Forum User
VOC Member
On key thing to check on t he MKII's is the float levels as then are never correct from the factory. On premiers I like the level to bring the float just even with the edge of the float bowl..

Worth a check..

Cheers Eric

Any body know about Mk2 s, I fitted one on my Comet, Flash Spec', A year or so ago, Thrilled to bits, 30 mm. Jetted as they supply.
Just fitted 2 to my ex L/ning, Same setting, Same size, No Fast idle !, When on choke.
Goes like stink, Mind you, Just got off the Comet !!.
I wonder if the slide, 3 , Is too rich ?, And that is upsetting the choke ?.
 

ericg

Well Known and Active Forum User
VOC Member
"On the other hand if you are interested in puzzles that change as you try and solve them you can't do better than an old concentric."

Tim, this is also valid for every component of our Vincent or any other old Brit bike.
A Girdraulic will never be as good as a modern pair of forks, the motor as good as it is will never be a match for a 21st century engine, etc. Where do you stop?
Where is the point of riding an old bike with modern components everywhere?
Why not buy a modern machine in the first place?
 

Marcus Bowden

VOC Hon. Overseas Representative
VOC Member
Eric my handsome, If I bought a modern bike I would have to pay for
A) road fund licence,
B) higher insurance,
C) servicing
D) allowing for depreciating
E) after ten years what have you got? an empty pocket and a bike worth very little
F) last but not least, not riding the thing I like the most, knowing it intimately and being able to fix it no matter where Modern stuff you must have a mobile phone and a plastic card,
Blue lights, indicators, hazard, heated grips, longer footrests, next time the seat is recovered I'll fit a heating coil as I tried a BMW that had it and it was nice, anything they have I can have too and far cheaper.
 

ericg

Well Known and Active Forum User
VOC Member
Hi Marcus, I hope you are well now.
I can't believe you are riding Vincents for so many years only because they don't depreciate or because they are cheaper to run than BMW's!... :)
 

vibrac

Well Known and Active Forum User
VOC Member
I don't think you should compare Concentrics with Girdraulics or Vincent twin engines. After all they are a later abortion the result of value engineering and penny pinching further down the slippery slope of lost quality than Monoblocks exacerbated by poor copies after their parent firm went west. I think they can join some or the other abortions of the sixties that stuffed the British motorcycle industry like the aerial three.
At last count I have a modern generator a modern carb avo suspension modern tyres and electric start. They as far as I can see only enhance my enjoyment of a machine built when quality was still a watchword of British industry.i also have a 1925 and a 2011 bike in original trim
 
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