I believe the R has a an even lower first! That will make the gap bigger! I have the NX 2nd and Euro 5th. Not sure a stock bike will pull the fifth well unless overall gearing is pretty short. It's the equivalent of making the stock fifth a counter shaft sprocket taller, or three in the rear sprocket. Pretty tall. A good solution though for people who like billy goat trail gearing to be able to run on the freeway, or for people with modded bikes to be able to cruise at lower RPMs.