Any generic M8 crank bolt or any M8 hardware store bolt plus the thickest washers they have. Cycle specific ones will take an 8mm Allen key which is a slight advantage, but hex head are fine too. Self extractors are not necessarily a great idea, it's not like you're pulling cranks in the field.
Any generic M8 crank bolt or any M8 hardware store bolt plus the thickest washers they have. Cycle specific ones will take an 8mm Allen key which is a slight advantage, but hex head are fine too. Self extractors are not necessarily a great idea, it's not like you're pulling cranks in the field.