Hi. I recently replaced the rear sprocket on my Bulls Sturmvogel E Evo 2016 model (https://electricbikereview.com/bulls/sturmvogel-e-evo/) which is equipped with a Shimano Nexus 8 speed Internal Gear Hub. In doing so, I may have replaced it with one with different number of tooth resulting in a slower bike. Unfortunately, I disposed of the old sprocket before realising the reduction in speed. Would anyone with a similar bike and configuration pls. tell me the size of the rear sprocket? Thank you.