On Sunday, 16 July 2023 at 10:02:54 am UTC+10 John Hawrylak, Woodstown NJ wrote:
To address the Chain Line Question. Assuming if you have a PERFECT Front Chain Line (FCL) with the triple (middle ring lines up with middle cog), then If you with: Option 1, remove Outer ring, the FCL needs to shift INWARDS, 1/2 of the spacing between the middle and inner ring. This is typically 6mm, so you need to shift the crank INWARDS by 3mm. You need a BB with a drive side distance 3mm *less than* you have currently. This will also give you a lower Q. Option 2, remove Inner ring, the FCL needs to shift OUTWARDS, 1/2 of the spacing between the middle and outer ring. This is typically 6mm, so you need to shift the crank OUTWARDS by 3mm. You need a BB with a drive side distance 3mm *greater than* you have currently. This will also give you a higher Q. You've got this the wrong way around. If you remove the outer ring, then the crank needs to be moved outwards, because the chainline is now between the two remaining chainrings rather than being on what was the middle ring when there were three. And vice versa if you get rid of the granny. Nick Payne -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/0969d282-eff9-4ab2-ba36-078a5ac18591n%40googlegroups.com.
