Campa Centaur triple and Engagement (Salsa) chainrings
My wife needs a little help in some of the tougher mountains here (not that I don't, but I'd probably never admit it).
Along those lines, I do find that after more than three months here, I am hardly ever in 30. Though we did 107 Km the other day, and were surprised at about 80 Km by a mountain I had not seen on the map. No way to go but up, and I used all I had and could have used more.
We have Campa Centaur 9s 30/40/50 triples on our bikes. I see at Branford's site that they have some inner rings that go as low as 24, and are compatible with some Campa equipment.
Question: is the 30 on our bikes 74 mm? The blurb at Branford seems to indicate that it is, but it isn't easy to measure without taking the bike apart.
The front der has a specified range. We have 50/40/30, now 50/40/28. The max range of the der is 22 teeth (difference of max and min chainrings). As a result, the 26 (not 24) would have created too great a span. Looking at the der, and the "vertical" travel it can seem to accommodate, it looked too close to call.
Would it work? Possibly - there is usually a little fudge factor in the specs. But I didn't want to spend the money to find out.
I fitted a 26t to a Mirage 8spd triple, with 39 and 50 rings. It was really useful on steep climbs, but gave me no-end of hassle, dumping the chain onto the BB. The front mech moves diagonally and shifts the chain too far horizontally, for the extra verical drop.
I replaced the chainset with a Shimano LX for some seriously steel hills, and my mechanic lowered the front mech. He is really good at setting up bikes and the Campy shifter copes easily with the range and size of the smaller rings.