Amal MK 1 carburettor - clearing blocked pilot jet passageway. 

Thank you Paul. Have exactly those symptoms, spitting back through the carburettor and very poor idle. Will have a go at cleaning out my carb.

My friends and I use the smallest guitar string; I think it is .009”, very strong and stiff. Worked on my ‘69 Bonnie nicely. Possible to drill and tap the opposite side and use it for access on the close side and plug it after clearing. Appreciate your site !!

what a great video . very clearly presented , I have exactly the problem with the poor tick over you describe. Will now attempt to correct it as shown. Many thanks .

Thanks for making this tutorial , I'm having some real problems just like you have described. Spitting back through the air filter and putting the engine out and continuous stalling at lower revs .😫..

I pull a wire from a wire brush for this kind of job, very stiff and works well.

Cleaned my 72 a65 thunderbolt carb pilot jet like this tick over like a watch thanks

Paul remember the two holes in the center on the bottom of the throttle tube on either side of the back of the slide. The tickover fuel and air has to have somewhere to go after they have been mixed. Those two holes must be clear as well.

Very useful video. Thanks for posting.

pure gold

Great Video - Thanks Paul

Thanks Paul, good advice

my 1967 trophy was only running on one cylinder and wouldn’t idle tried your trick used the wire out of a mig welder now she runs perfectly thanks

The hole from there into carb throat gets blocked as well, you can just drill out the jet with a 2.0mm drill taking care down the pilot screw hole taking care not not to damage the air screw seat you then put a new jet into the threaded boss in the top of the carb body float chamber usually used for 2 strokes

Guitar string (thinnest) worked a treat for me. Pilot jet clear, now off to buy new set of strings!

Great info, thanks

thank you. I think that the blocked pilots are the problem on my T140v will strip them tomorow

thank you, I cleaned mine a couple weeks ago, will have to do it again. starts but no idle. Initially i didnt have the right wire and thought it was good enough.. not so.

The primary discharge ports, located on the floor of the venturi, clog up. The only way to clear them is to prick them clear. I use guitar string. It worked like a charm of the worked like a Charm on my 72 Trident..

Thanks for sharing your knowledge its very much appreciated, my 68 A65 had rust particles in bottom of the float bowl and now wont start, I think these passage ways must be blocked I will have a go at clearing them 👍

Hi Paul I am Kumar I have just fitted new carb ( Amal mk1 concentric 26mm) and pod filter looks same as one that picture above on my bike ( 1984 Royal Enfield 350cc ) I have few questions to ask if you don’t mind and I guess as you are using Amal carb you would be able to clarify my doubt my questions are followe 1 I don’t find any difference of using Amal carb as I was using mikarb before or Am I tuning is not right way? 2 I feel the throttle cable is just a bit hard to throttle after changed to Amal carb ( have been told by mech just because of the spring in the Amal carb is high tensed one than one was on mikarb 3 after changing the airfilter from the Indian made box type to Amal pod one which gives me ‘kisk’ ‘ kisk’ noise or is that normal with that sort of filter as I never used that before replies will be much appreciated thanks

Would squirting a big of carb cleaner in the holes help things along?

Good advice. Method to re-seal drilled blank would be good to know.

Just an idea, but a fine gauge guitar or banjo string might be fine enough. Thanks for the clear info on that.

This is very informative, thank you. It's very hard to figure out these carbs when you start. But do you know if it's possible to replace the brass insert? After one hell of a game, clearing & re-blocking several times, I finally got the bike running okay, but too rich. Air screw is out over4 turns now, still black plugs so I fear I've over-done it

16 thou is the hole size.which is just over 0.4 mm

How did you seal up the hole you drilled?

16 thou or 0.4 mm drill bit,once dunked some for 48 hours in white vinegar,

Hi Paul great video question My bsa a65 concentric is pretty new ran great last year now it’s well blocked Do you know the max size drill I can use it says #78 drill equals to .40mm If I use a 0.6mm drill would this do any damage to the pilot system Thanks a lot phil

Hi Paul, thank you for making this video, I have a 67 tiger and it's hard starting, it only stays running when I'm working the tickler and the throttle at the same time. Do you think this is my issue a blocked passageway. Thanks if you could please respond.

The old gasoline formula probably caused this . See Uncle Tony's Garage on ethanol gas.

camera on tripod would had been a good idea i feel drunk after watching the vid

Oh dear, another prime bodger. pokeing steel through a jet not a good idea at all ! Much easier to buy a 78 wire guage drill (16 thou) and use it to clear and resize the jet. Easy to remove and replace the welsh plug, this will give access to all jet and discharge holes.