McFarlane Aviation Products - 7140

Part Number: 7140

KIT, Rotax Throttle Springs

Product Details

Rotax Throttle Return Springs
Stop throttle creep!


A common complaint about the Rotax 912/914 engines is that the throttle return springs are too strong. McFarlane stocks a variety of springs so you can choose the one that best fits your application. All McFarlane throttle controls for Rotax engines include P/N 7140 springs.


Unique hook design for left and right applications provides for better fit and retention.


  • New design limits potential contact with adjacent parts
  • Less than half the strength of the original stock Rotax springs
  • Tailored for Rotax engines, including the Vans RV-12 aircraft
  • Prevents throttle "creep" due to excessive return spring force
  • Requires 1 per carburetor (2 per engine)


Spring P/N Relaxed Spring Length (max in) Approx. Pre Load (lbf) Spring Rate (lbf/in)
6822, Red, Left 1.6  1.5  2.1-2.7 
7235, Blue, Right 1.6 1.5 2.1-2.7
Rotax Original 1.8 (approx.) 2.0 8-12 (approx.)

Note: Installer is responsible for determining whether this spring is an appropriate substitution for their application. For use on non-certified aircraft.


Related Product Catalog Pages

Control Eligibility and Catalog Information

Frequently Asked Questions

I purchased a laser engraved knob and the thickness of the marking is very shallow. What kind of wear resistance can I expect?
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What is the minimum bend radius for my engine control?
How do I trim my engine control to length?
My Vernier-Assist Throttle control came apart during installation or maintenance. Can it be put back together?
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