The reason behind upside-down forks

TELESCOPIC forks do a difficult job. Not only do they have to keep the front tyre in contact with the road under a wide range of conditions, they also have to withstand braking and steering forces that try to twist and bend them in all directions. The problems are amplified on the track, where forces are taken to extremes. In the late 1980s, race teams found that by turning their forks upside-down, they improved their bikes’ handling. And upside-down forks are still with us. In fact, most serious sports bikes have them. But how does turning forks upside-down help and are they really better than conventional ones? To find the answer, you need to look at the individual parts of a telescopic fork and what you want to achieve. Forks need to be rigid, to function well as suspension parts and be as light as possible. Let’s look at suspension operation first as there’s almost no difference between inverted and right-way-up forks in operation. A fork generally has a spring and damping unit
TELESCOPIC forks do a difficult job. Not only do they have to keep the front tyre in contact with the road under a wide range of conditions, they also have to withstand braking and steering forces that try to twist and bend them in all directions. The problems are amplified on the track, where forces are taken to extremes. In the late 1980s, race teams found that by turning their forks upside-down, they improved their bikes’ handling. And upside-down forks are still with us. In fact, most serious sports bikes have them. But how does turning forks upside-down help and are they really better than conventional ones? To find the answer, you need to look at the individual parts of a telescopic fork and what you want to achieve. Forks need to be rigid, to function well as suspension parts and be as light as possible. Let’s look at suspension operation first as there’s almost no difference between inverted and right-way-up forks in operation. A fork generally has a spring and damping unit

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COMPLETE ASSEMBLY UPSIDE DOWN / INVERTED FRONT FORK TUBE