Turbo Edge Adjustable Syphon

The Turbo Edge is the world’s most compact syphon, guaranteed to fit more places than any others.



Dudley’s Turbo Edge is the world’s most compact syphon, guaranteed to fit more places than any others, with absolutely no compromise on flush performance. Manufactured in the UK by Thomas Dudley, Turbo Edge is guaranteed to fit into all types of lever-operated cistern currently available, offering plumbers, installers and designers a versatile, easy-to fit and easy-to-service solution even in the tightest spaces.

Fully adjustable from 7.1/2″ to 9.1/2″


  • Dudley’s Turbo Edge is the world’s most compact syphon, guaranteed to fit more places than any others
  • 6/7/9 Litre volume adjustment guaranteeing optimum flush performance
  • Fully captive yellow fixing pin does not need to be removed to install syphon, easing installation.
  • It has a 2-part design that enables the syphon body to be simply removed from the cistern leaving the white downleg in position. This feature enables the Turbo Edge to be serviced in under 5 minutes without disconnecting water supply and dismantling cistern
  • Retrofits Dudley Downlegs over 7.5"
  • The Turbo Edge is the ONLY syphon you will ever need
  • Fits all syphon flush ceramic and plastic WC cisterns.
  • Stock Item - Available for next working day dispatch


Yes! The Turbo Edge is the only toilet syphon that will retrofit onto existing Dudley downlegs (including the Turbo 88 Adjustable and Fixed Height, S44R and S1-11 syphons).

A syphon can be used as an internal overflow device, as long as the spill over point of the syphon is below any other external hole within the cistern body, normally the lever hole.

To convert the Turbo Edge syphon to single flush mode, disconnect the lever and unlock the yellow snap pin from the syphon. Remove the top spillover section, the remove the main blue upleg body section. Remove the metal C link and washer to release the piston rod. Remove the piston assembly from the upleg body section. Replace the stepped plastic washer on the top of the piston rod with the single flush plastic washer stored on the rear of the body of the syphon. Reassemble piston to the upleg body section, replace the C link, refit the upleg body to the white downleg, refit the spillover section and lock in the yellow snap pin. Replace the lever assembly and reconnect to the C link.

To find the correct height of the required syphon for a cistern, measure the depth of the water level line, within the cistern, normally marked at the back of the cistern, and then add 1” or 25mm to this measurement. This will give you the height of the required syphon. (Cisterns fitted before 2001, would have an original syphon in them that would be approx. 1 ½” or 40mm taller than the current requirements).

When fitting a syphon to a close coupled toilet, you need to ensure that the threaded tail of the syphon is trimmed back, to ensure that the syphon flush is not throttled back, giving you a poor flush. We recommend that the tail is trimmed back to 2-3mm from the back nut.

A syphon is measured from the bottom flange of the threaded tail, to the spill over point of the syphon, this is the effective height of the syphon. When choosing a syphon the height stated will be the height to the spill over point and not the overall height of the syphon (i.e. an 8” syphon would be 8” to the spill over, whereas the overall height would be 10”)

The operation of the dual flush syphon, is to flush and release the lever to give you a full flush, and to flush and hold the lever down, to give you a reduced flush. By holding the lever down, this lifts up two washers (one small blue plastic and one small black rubber) that are located immediately below the metal C link. When these washers are lifted up, this allows air to enter the syphon and breaks the syphonic action, the water level in the cistern will drop to just below the top of the syphon body, therefore giving you a reduced flush.

A syphon will internally overflow when the water level within the cistern reaches the spillover point. The water will trickle over the spillover point, and run down the downleg of the syphon, and into the toilet bowl.

These are to reduce the flush volume of the syphon within the cistern. By removing the plugs you will reduce the volume of water supplied on the full flush. If no plugs are removed, the water in the cistern will drop to the bottom of the syphon body. If the bottom plug is removed, the water in the cistern will only drop to this level. If the top plug is removed, the water in the cistern will only drop to this level.

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