That is beautiful mate, where did you get the stroker crank? I'm looking at this big bore kit with stronger rods and asymmetrical cam from Flatracer in the UK, what do you think of it? Cheers, Terry.
http://flatracer.com/#/bmw-performance/4538136890
I made crank myself. It was most delicate work of all. Because I machined conrods ( not me, in machine shop!) I can choose smaller flying bering, from stock 48 mm I make 45mm . That s why I can ,when machining crank , make 2mm offset .Center of flying bering in that case move for 2mm and make longer stroke. very simple bat must have good and skilled machine operator. But in that case all original surface hardening is gone and only base material left on crank. Then cranks must ( friction surface) be re chromed . That is the trick, but after do it all right that crank is allmost 100% wear free!I use con rod berings from BMW car racing program. From E 36 engine . And pistons are for early M3 models 4 cyl. 2.3 lit engine. Also cast cylindres for that pistons because of specific dia. Stock BMW R 100 is 94mm and mine is 93.43 . I want to cast cylindres anyway . Cast it at Solarevic Machine works . We make this year first few replicas of Fontana drum brakes 250mm.
Think that light pistons and con rods are better investment than big bore. Asymmetrical cam is ok. Give useful, wide power and torque band.