Motorcycle Piston Rings For BMW R850GS R R850RT R900RT 1994-2009 Work for Fit For BMW R850GS 1996-2001 R850R 1994-2002 R850RT 96-02 R900RT 05-09 motorcycle 87.5MM bore cylinder engine overhaul assembly Align cylinder mounting matching structure; support direct replacement assembly without or auxiliary fittings cylinder compression ratio; reduce consumption power loss during long distance touring riding Adopt cast piston rings with uniform surface finish; deliver tight consistent contact with cylinder wall Made to match 87.5MM standard bore dimension; fit inner cylinder wall to eliminate assembly clearance gaps