I'm looking to get a new x- ring did chain and maybe renthal sprockets and I've currently got stock 16 ft 45 rear with 525 chain and it has 138 links(extended)... But I'm wanting to go 14 ft and 50 rear with a 520 setup... So will I need a 150 link chain and the shop I take it to can remove the extra links or do I need an exact number when purchasing new chain combo? Any help is much appreciated