130bcd chainring on 135bcd crank?
I really really want a 38 tooth on my Franken-gravel bike. This would allow me to go with the holy grail of gravel 1X, 38x 10-42.
When you run the numbers, what it offers over 40 x 11-42 is substantial.
So the bike in question has a 135bcd Campy Chorus crank paired up with an IRD BB (pretty much the best square BB still available). This results in a perfect chain line.
Switching to an older Shimano 130 BCD would move the chain line in 4.5mm. My chain stay will clear this, and I could mount the chainring on the outside instead of inside of the spider. This would work ok, but I don't want to mess with it and I don't want to hunt eBay for an appropriately high end square Shimano crank from the 90s.
So this finally brings me to the question of the day. Using a file and elbow grease, can a 130bcf chainring fit on my current Campy crank. I think I could file the holes in the ring pretty oval. I would also need to file the inside edges of the chainring down to fit within the tabs of the spider.
Has this been done? Did it fall apart? Did it spin round?