Projects to improve and customize your Fox model engine

Modifications and Projects
to enhance your Fox Engine:

Project #1 - How to "Smarten Up" your Fox Eagle .60
If you have been experiencing problems such as finicky needle settings, "flameouts", running hot, you may be interested in these modifications. Applicable to Eagle .60 engines versions II through IV.
Project #2 - Make an "After-Muffler"
This easy to make addition to your Fox tilt-up/dn series muffler lowers sound level by at least 5db and does not reduce the output power. Inexpensive and light-weight too.
Project "HUSH" - by Duke Fox
A reprint of a test report done some years ago by Duke Fox with the results of his efforts to reduce the noise level in 2 cycle engines. Interesting reading for those pursuing after-muffler and propeller options to reduce noise. (pdf document)
Project #3 - Improve your Fox .50BB
Modifications to the head button will lower the operating temperature and make needle settings less critical.
Project #4 - Getting the best from your Fox .40
Although it has changed little in appearance since its introduction in the mid 80's, there have been numerous internal changes over the years that have affected running characteristics. Here's what you need to know to get the best from your Fox .40.
Project #5 - Taming Your Fox .74
If you have been experiencing problems such as finicky needle settings, flameouts, running hot, and lots of deadsticks, you may be interested in these modifications.
Project #6 - Determining Engine Condition
No amount of adjusting and fiddling will help an engine that is damaged, worn, or just plain "cooked"". This page provides some simple procedures you can perform to help determine the condition of your Fox engine.
Project #7 - Taming your Hawk .60
For those of you with the facilities, and machining skills, these modifications will allow your Hawk .60 to reveal it's true, and considerable, potential. Note: not for the novice engine tinkerer!
Project #8 - Taming your Fox 1.20 Twin
Since the Eagle II .60, upon which the 1.20 is based, exhibited some problems, it should not be too surprising that the 1.20 twin does as well. Fortunately, the 1.20 responds just as well to the same modifications that we have used to tame the .60.
Project #9 - Improve your Fox .45BB
The .45BB has been a pretty good engine over the years, but we did stumble upon a way to improve it.
Project #10 - Improve your Fox .25BB
The current .25BB is a great little engine just as it is. However, if you have an earlier version some improvements can be made.
Project #11 - Improve your Fox .19BB
While it had loads of power for a .19 there were also a few problems with this engine. Hot running and carburetor midrange problems are addressed here.