I am familiar with the AMAL concentric Mk1 carb but is the Mk1.5 the same as a Mk1 with the addition of a choke.

The Mk2 looks different externally but what are the changes from the Mk1 & Mk1.5. Is the jetting & slide common to all three types ?

Edited January 20, 201412 yr by trialsrfun

does the m1 have what i call a dabbler that pushes the float down to over fill the float chamber to act as a choke , this was probably changed to a proper choke on the mk1.5 then there was a mk1.5 with a fuel bowl held on by a spring clip then the mk2 with plastic threaded top and square fuel bowl id say the jet sizes are simulare if the venturi (inside bore diameter ) is the same give or take depending on the motor set up they have been tuned to ,from what i gather , you can google the differnt carb images

I am familiar with the AMAL concentric Mk1 carb but is the Mk1.5 the same as a Mk1 with the addition of a choke.

The Mk2 looks different externally but what are the changes from the Mk1 & Mk1.5. Is the jetting & slide common to all three types ?

Yes, MK1.5 is the MK1 but with the MK2 choke device. As far as I know, the internal workings of the MK1 and MK1.5 is the same. I've heard it said that the pilot system differs but from what I now and remember of the MK1.5 that I had, they are the same, someone with more knowledge will no doubt clarify. The jets, slide, needle etc are common to both.

The MK2 uses the same jets as the MK1 but has a different slide, so not interchangeable. Not sure about the needles, can't remember. I think it has a different, more efficient pilot circuit than the MK1, but again, someone with more knowledge will clarify.

MK 1.5 is available in different choke sizes, has a proper enrichment device instead of a tickler and has the pilot jet at the front centre of the body instead of at the back and on one side.

Mine seems a lot more waterproof than the MK 1 when washing the bike, maybe it's removing the tickler that improves it