CX gearing advice Home › Forum › Bike Forum › CX gearing advice Viewing 15 posts - 1 through 15 (of 15 total) CX gearing advice chriswilkMember Got a CX bike for my daughters to race on, age 11 and 13. Gearing is a bit high for them. It’s 36/46 double and a 12-25 10 speed at the back. rear mech is a 105 short cage. The spec on the mech says tooth capacity is 33t, so I could go for a 12-30 cassette. Anyone running a 30t sprocket on a 105 short cage? is it OK? Posted 4 years ago umop3pisdnMember Don’t forget about BC gear restrictions, I think 46/12 is too big for the age categories your children are in. Why not just single ring it? Posted 4 years ago chriswilkMember I can’t imagine they will ever use the big ring in a CX race anyway. Need to make the bottom end lower, that’s all. A new Tiagra cassette is only £16, much cheaper than a new chainset. Posted 4 years ago The Swedish ChefMember I think that gear restrictions might come in to play here: Youth C Under 12 at 1st Jan 6.05 metres 76 inch 39×14 / 42×15 / 45×16 / 48×17 Youth B Under 14 at 1st Jan 6.45 metres 80 inch 39×13 / 42×14 / 45×15 / 51×17 Posted 4 years ago chriswilkMember yes, yes, ok. Never been checked on a CX race anyway that I know of. I will make sure that it is single ring only for the racing, and so 36*12, and will probably get a 34 ring. My question was, will a 30t sprocket work ok with a 105 short cage mech??? Posted 4 years ago SpeshpaulSubscriber “My question was, will a 30t sprocket work ok with a 105 short cage mech??? “ why didn’t you say that in the 1st place:-) it might is the answer you are right on the edge, and accidental big – big and some cx cack might do for it. I’d be tempted with a MTB rear mech and cassette- 9 speed mtb mech with road kit. Posted 4 years ago wwaswasSubscriber if you’re ditching the big ring anyway then the big/big issue disappears? Posted 4 years ago The Swedish ChefMember Yes, get rid of the big ring and they’ll be no issues on either front. Posted 4 years ago chriswilkMember I thought I had, with a bit of background and then the last line of: “Anyone running a 30t sprocket on a 105 short cage? is it OK?” will go for it anyway, big ring will be ditched/disdabled for CX Posted 4 years ago JaseMember I don’t think the gear restrictions apply in CX. My daughter has been racing for 3 years and never been checked. Posted 4 years ago MrSmithMember I don’t think the gear restrictions apply in CX. My daughter has been racing for 3 years and never been checked. what region is that in? Posted 4 years ago JaseMember Central Posted 4 years ago MrSmithMember Thanks. they do apply, somebody isn’t doing their job properly. 😀 Posted 4 years ago Edric 64Member I use a 32 tooth ring most of the time the big ring only gets used on the tarmac bit of crosses .I reckon a smaller ring than 36 would suit a child Posted 4 years ago chriswilkMember in reality though, all the junors are running in their easiest few gears. There are no places where it is possible to churn a high gear, well not in the scottish CX series anyway Posted 4 years ago Viewing 15 posts - 1 through 15 (of 15 total) The topic ‘CX gearing advice’ is closed to new replies.