In response to the requests for information regarding Centax type clutches, we have put together a series of articles that explain the way they work and what parts are involved.
Please note that I only have knowledge of the Serpent and PB Racing products, so cannot cover all possible variations of this type of clutch.
Note: If I get the opportunity, I will add further information covering the evolved versions of the Centax clutch.
There are basically two different types of clutch available for the remote controlled model car today, both use centrifugal force to engage the drive from the engine to the gearbox/wheels. The first type, which uses just the force of two or more clutch shoes will be covered in a different article, but the principle can be seen in action in the animation at the bottom of the page in our article on Two Speed Transmissions.
This series of articles concentrates on Centax type clutches, which derive their name from the fact that both centrifugal and axial forces/movements are involved. The centax type of clutch is more complicated and has far more parts than other types of clutches.
The name Centax is that given to it by the inventor, Serpent Model Cars, and is used throughout this series of articles as it has become synonymous with this type of clutch.
As stated above, the original Centax clutch was made by Serpent some time ago and variants have been manufactured under many different names, all with slightly differing designs. PB Racing made a version using the name of PB-Tec, and the Picco version was called Synchro. All the major manufacturers have made a version, each with their ‘improvements’, but they all work using the same basic principle. The PB Racing Dart 1/5th Scale Car used a variant of the PB-Tec clutch, which we have a little bit of information about under the PB Dart Modifications section.
This article is the first of the series and give descriptions of the parts along with illustrations. It uses the PB Racing variant primarily with the Serpent differences noted and illustrated.
This second article in the series shows how the Centax type clutch works through the use of illustrations and an animation.
The third article in the series gives notes about the materials used and potential pitfalls of a suggested modification as well as a link to other relevant information on the site.
We have designed and made our own adjusting tool for the Serpent Centax clutch. This article gives the reasons why as well as construction details.