Do You Have New Concentric Carbs?
Current production Amal & Wassel carbs almost always arrive to us with adjustable ferrules screwed into the carb tops. While Norton and BSA utilized the throttle ferrules, Triumph fitted throttle cables with top-hat shaped ferrules designed to seat into the top of the carburetor. So, if you’ve purchased a new carb or carbs for your Triumph, how do you install them with stock cables?
Drilling Amal Carb Tops
We get some frustrated calls here at The Bonneville Shop from people that have purchase new concentric carbs and their old throttle cables are too short and won’t fit correctly. Many times, customers want to purchase new cables to suit the carbs, but as long as the old cables are still in good shape, new cables aren’t necessary. In fact, due to the limited space above the carbs on Triumph twins, keeping the adjusters fitted to the carbs can be more trouble that its worth.
Current production Amal & Wassel carbs almost always arrive to us with adjustable ferrules screwed into the carb tops. While Norton and BSA utilized the throttle ferrules, Triumph fitted throttle cables with top-hat shaped ferrules designed to seat into the top of your new concentric carbs. Current production Amal and Wassell carbs are almost always shipped to us with adjustment ferrules fitted in the carb tops for both the throttle and choke circuits as carbs are not typically setup for any particular application when they leave the factory.
So, if you’ve purchased a new carb or carbs for your Triumph, how do you install them with stock cables?
Really you have 2 options: The path of least resistance is to re-use your existing carb tops (assuming you aren’t installing different carb types – If you are replacing monoblocs with concentrics obviously this won’t work) or you can carefully remove the threads from the new carb tops.
Chances are you already have everything you need to modify the carb tops in your garage or workshop – A drill, and an appropriately sized drill bit, usually ¼” but you’ll want to measure your throttle cable ferrules prior to drilling. (show close up of measuring ferrules)
Here we go (close up of carb top, turn on drill, drill out threads)
And there you have it, now the cable seats into the carb top, the throttle slide drops completely into the carburetor body and you are ready to fit and tune your carbs.
If you have questions about any classic British spares, don’t hesitate to give us a call: 720-570-7884, text: 720-260-4271 or email: orders@thebonnevilleshop.com
Triumph Norton BSA Pilot Jet Genuine Amal PN# 622/502 A
$46.61 – $101.07
Genuine Amal Throttle Slide Hard Anodized # 3.0 Cutaway 600 Series Concentric Carburetors (1) PN# 622/060 3.0 HA
Original price was: $82.95.$72.95Current price is: $72.95.
5/16 inch Fuel Petrol Gas Hose Assembly Crimping Tool Set PN# TBS-3001
$116.64 – $128.97
Triumph Norton BSA 90 Degree Fuel Pipe(s) PN# 82-3335 F3335
$11.24 – $16.74
