Good evening to all of you,
First of all thanks for all the replies you posted, I wasn't able to answer them because I reached my 24h limit of 5 post.
BCD is indeed 130mm, small is 42, big is 52. New rings can be a little less I think.
I'll try to answer everyone's questions/remarks.
First of all I also very much like these cranks so if possible I would in fact like to keep them 🙂.
I have looked around and read into different topics on this and concerning turning the chain rings around, I thought of that as well, but the offset sideways would change ( two chainrings would lie 2 mm further away from each other and I don't know if this would cause problems shifting (shifters are on the frame, I don't know if these have 'fixed' positions per gear or if they can be freely moved to fit the gear,...)
I have found fairly cheap new chainrings (online so comparisons are difficult to make) I think should work (stronglight) but I'm worried on three things.
1) the new chain rings are for a 9/10 speed so I assume more narrow.
2) the offset sideways, so for possible shifting issues.
3) the inner diameter of these chain rings, if the would fit the cranks (so not bcd but the smallest diameter of the chainrings). I do however not see this point as the biggest issue 🙂. Grinders etc.
For the table you shared, for bcd 130 the teeth don't match so I'm not sure what to make of this.
Would you take the chance with the 9/10 speed stronglight? Maybe choose an 8 speed chain and hoping for the best on my 7 speed casette?
Please feel free to share your thought, I find this all very fascinating.
Thanks and with kind regards Dieter