This is specifically made for the Rockrider E-expl-520/520s. I brought this from Eplus from Spain, it unlocked my Rockrider E-expl-520 to 30mph, only used for around 150 miles. selling as i sold my bike on a private ebike sale site that wouldn't allow modifications. I also changed the chain ring from the original 34tooth to a 48tooth so the warranty wasn't affected, so if yours is still under warranty you'll know that they check by the amount of motor rotations, with the extra teeth it evened it out and I know this because I had a separate GPS speedo attached and if anything its was very slightly under by 3 miles over the 150 miles I done. with this bit of kit you can comfortably ride at 20-25mph on a flat, reaching 30mph on downhill roads. I've included the the chainring too.
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