The naraku crankshaft for derbi senda 50sm 2006-2020 is part of the latest collection from naraku.Features: high quality crankshaft from naraku made in taiwan produced according to the oem guidelines of japanese vehicle manufacturers for perfect repairs and durabilitythis heavy-cheeked hpc racing crank increases the pre-compression in the cases for improved filling. The extra inertia improves performance and the performance moves to the upper rev range. The crank design, with plastic inserts, only slightly increases the mass over the original making it ideal for 50cc. Delivery includes small end bearing.Specifications: product name: crankshaft type: race units: each to fit: aprilia rs4 50 2012 replica european models aprilia rs4 50 2012 european models aprilia rs4 50 2013 replica european models aprilia rs4 50 2013 european models aprilia rs4 50 2014 replica european models aprilia rs4 50 2014 european models aprilia rs4 50 2015 replica european models aprilia rs4 50 2015 european models aprilia rs4 50 2016 replica european models aprilia rs4 50 2016 european models aprilia rs4 50 2017 replica european models aprilia rs4 50 2017 european models aprilia rs 50 2006 european models aprilia rs 50 2007 european models aprilia rs 50 2008 european models aprilia rs 50 2009 european models aprilia rs 50 2010 european models aprilia rx 50 2006 european models aprilia rx 50 2007 european models aprilia rx 50 2008 european models aprilia rx 50 2009 european models aprilia rx 50 2010...