[Slappy]

Good morning all

I am hoping to get out on my bike again in the next couple of weeks, I finally finished the bike last year and got a small amount of riding in, ( very small ) as it was running rich black smoke, a couple of older builders took a look when I was at a show and tried adjusting it and said to change the pilot jet first, so I have replaced the pilot jet from a #17 to a #15, I haven't attempted to start it yet but is there a base setting for the pilot jet and do you need to make any adjustment's to it,  I have tried looking for a guide on setting the pilot jet but can't find anything
any advice would be great
thanks Dave.

[Adrian II]

The original Amal Mk1 Concentric didn't have a choice of pilot jests on 4-stroke applications, just a fixed brass bash buried deep inside. The Premier has reverted to a separate pilot jet as they are much easier to keep clean, but this means there's no readily available history of pilot-jet swapping! Normal practice is to have the pilot air screw about 1.5 turns out.

The old Redditch 500 Bullets used a 30 pilot jet, but that was in the older Monobloc carb so not necessarily much help!

What part of the rev-range was the black smoke occuring at?

Tuning info here if you haven't already seen it.

https://www.jrcengineering.com/technical-support/amal-concentrics-tuning-and-jetting/

Of course you could try here:

https://amalcarb.co.uk/contact

A.

[Slappy]

Good afternoon Adrian

the black smoke is on tick over and just off, I have got a gunson colortune  that I have tried and this confirms it is rich, I will start with 1.5 turns and see how we go from there as long as it doesn't run lean

[Paul W]

Bear in mind that if the fuel level sits too high everything runs rich, but then improves with a wider throttle under load.

[Slappy]

Thank you Paul

I will try the basic setup and use the gunson as well and just get some miles in, and see what I get