Don't you mean 20mm pin and 45mm big end. They have a 42mm crank but the big end bore is 45mm. I would check to see if you have ordered the correct ones. 40mm Crank is about 43mm big end bigend bore. I have just ordered a set of Pauter rods and I have ordered 20mm pin with 45mm big end to fit a 42mm crank.
