I have cranks with 4 holes for outer and middle rings attachment. There are no holed for inner ring attachment. On my other bikes crankset middlering has 8 holes 4 for cranks and 4 for inner ring. I tried to take them and attach to my other outer chainring and cranks and put it on bike, everything works perfect. The problem is I can't find middle chainring with 8 holes for sale in my country or on ebay. Should I drill 4 more holes on my crank. Or what should I do please advise!
I. My other middle chainring with 8 holes, I can't find it for sale:
II. My crank inner side with 4 places for drilling maybe :D