WP43 Air to Spring Conversion Kit
WP43 Air to Spring Conversion Kit
WP43 Air to Spring Conversion Kit

WP43 Air to Spring Conversion Kit

Regular price $495.00
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KTM/Husqvarna ‘WP AER 43’ Air to spring conversion kit (ATS) is aimed to suit all the current AER43 Equipped Husqvarna and KTM 85 cc racers.

 Fits All 2018-2023 KTM, Husqvarna and Gas Gas 85cc Junior Mx Bikes

Recommended spring rate for rider weight ( without gear )

  • Rider Weight 35-40kg – 0.60 
  • Rider Weight 40-45kg – 0.64 
  • Rider Weight 45-55kg – 0.68 
  • Rider Weight 55>   kg – 0.72 

Our WP43 ATS Air to spring conversion kit is a complete replacement cartridge assembly for your current WP AER43 AIR Fork setup.  It is designed to completely remove all the Air system from your current WP43 Fork and replace it with a preload adjustable spring and cartridge setup.  High Quality Springs are available to suit varying rider weights.

Key Features  

  • Never have to set your air pressure ever again
  • Super easy install. Undo top cap , drain oil completely and remove base bolt. Our kit slides in as a complete replacement supplied with spring installed all ready to go!
  • Much more reliable fork
  • No Fade out or pump up in pressure over long moto’s highly noticable on these 85cc machines. We are measuring 3-4psi over 20 minutes at a high level!
  • A Constant feel in your front end that  is more consistent throughout the ride
  • Spring Pre-load adjustable minimal tools are required for fitment. If you have the Fork cap and basic tools to remove the standard OEM Air cartridge you will have the ability to fit up our kit.  Our cartridge kit is made from High grade 6061 Aircraft Grade Alloy , Chrome Moly rods and Anodised for a Factory Finish. Instruction manual included.


  • Fully Complete Cartridge assembly
  • Optional spring to suit this kit
  • Instruction
  • Decal Set 

Fork Spring Recommendations  – General Riding and MX Applications

These recommendations  are a guide only as fork Springs are weight and speed dependant.  For example a 44 kg A GRADE ‘Pro level’ rider falls into the .65kg/mm category but may well be better suited to a 0.70kg spring due to the much higher corner entry speed and the ability to hit large bumps at high speeds.  Please note this guide is for rider weight ‘without’ gear.

Please note we have had great results using one spring down for C level riders or absolute beginners on the 85cc machines. Eg. 42kg rider running a 0.60kg/mm spring for a plusher ride.


WP43 Air to Spring Conversion kit

  • Rider Weight 35-40kg – 0.60 
  • Rider Weight 40-45kg – 0.64
  • Rider Weight 45-55kg – 0.70 
  • Rider Weight 55>   kg – 0.72

For more accurate advice please consult your local suspension tech or send us an email.

Service Parts Available via catalog

Fork Seal Kits

Genuine KYB or Premium SKF Kits to complement the finest suspension builds

Genuine Slide Bushing

Friction Free suspension always install new slide bushing at service. Any dirt or build up in the teflon coating causes stiction and binding action

Genuine and Super Smooth

Eibach Ktech WP KYB

Only the best brands of springs. Outside of OEM we recommend Eibach and Ktech to ensure reliable accurate spring rates

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