Which pedal assist sensor (PAS) is most appropriate for my bike?

Which PAS should I choose?

During our order survey you will be asked which PAS (pedal assist sensor) is most appropriate for your bike. This can seem a daunting question at first- but don't worry, we're here to help.

The first distinction is between a PAS for a regular or Brompton bike. By "regular bike" we mean any NOT made by the Brompton brand and includes any other folding bikes. Once you have determined which type is appropriate, please refer to the corresponding section below. 

Our decision making tree at the end of this article will also assist you in determine which type you require.


Regular bike options

For any regular bike, we offer two types of PAS- creatively named Type A and Type B. These are designed for differing bike configurations- one fits in the gap between your pedal crank and bottom bracket, and the other fits if this gap does not exist. 

In order to determine which PAS is correct for your bike, you will need to measure the "Pedal Gap"- the space between your pedal crank and bottom bracket. If you are unsure how to do so, please refer to the below section. For any gap wider than 4mm, a Type A sensor will be most appropriate, whilst any gap smaller than this will require a Type B.

At this time, the choice between Type A and Type B is primarily for our R&D department in order to better inform our future product. So if you have any doubts about which type of PAS is appropriate, we suggest that you choose the Type B sensor due to its universal fitting.

Our Type A PAS slides inside any pedal gap larger than 4mm, and sits within this space as shown.




Our Type B PAS will affix to the inside of the pedal arm, allowing for it to sit within gaps smaller than 4mm. 




How do I measure my Pedal Gap?


In order to approximate the gap between your pedal crank and bottom bracket without the need for precise measurement, we suggest using 2 thin coins. For the UK, 2 pence pieces work best, whilst for the US and EU nickels and 2 Euros are the right choice. 



Brompton bike options


The pedal bike design of Brompton bikes was changed in 2013, which means there is a different distinction between Type A and Type B Brompton. For any Brompton manufactured after 2013, Type A will be required, whilst for those made before 2013, Type B is needed. For those made during 2013, please refer to the below instructional diagram in order to determine which is appropriate. 




Visual Guide



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