I’ve been running a 40 tooth big ring for about 3 months now. So much so I have to wonder why 44 is the default in the first place.
I used an FSA DH/SS ring with no ramps or pins and only 3mm thick. Definitely not ideal but it’s surprisingly hard to find a 40 tooth ring. I ended up having to use a 1mm spacer to get the shifting right since most geared rings are 4mm thick.
Two races and many hours on it and I’m convinced it’s gobs more useful than the stock 44 most cranksets come with. The only times I’ve gotten close to spinning it out is on long road downhills. For racing I’m thinking a 38 would be even more useful. To go even further, I think a 26/38 double ring setup could be the race ticket. The big test for me would be the steep climbs of the Thunderbolt course. I’m pretty sure a 26 would be low enough with an 11-34 cassette.
The bike JHK rode at Nationals has intrigued me. He ran a single 36 tooth chainring with the new sram XX 10 speed 11-36 cassette. Hmmmm.
XX is smokin’, but proprietary. I dig the cassette, but you have to buy the shifters, chain, derailleur, and cassette. Frustrating, but probably in my future one day. I’m looking at running a 30t road granny on my old 74/110 Race Face cranks, with a 38t big ring, on the 29. Not quite low enough for the mountains, but good around here. You can get the granny on ebay for $10, and J&B has the 38 with ramps, and most importantly, in black!