Cannodale caadx tiagra upgrade help gearing

stewartcjones123

2016 MODEL tiagra

fsa omega 46/36 crank 12-28 cassette

need help in choosing higher gear option. most of my riding at moment is road based with some slightly off road(gravel paths) most of my friends have road bikes.

I seem to only use the front ring and hardy touch second ring, so was wondering how I get more higher gearing

do I swap out chain set ie shimano and change bottom bracket, or can I replace chaining and cassette

the bit im struggling with is which gear ratios to go for ???

any help greatly appreciated

trek_dan

The easy answer is to change your 46 chainring to a 50 or 52. Look for a 5x110 10 speed outer chainring, any brand will do ie Shimano/SRAM. All you'll need to do is move your front derailleur up a little.
Although at 46-12 with a cadence of 90rpm you'll be doing 28mph, are you sure you need a bigger top gear?

keef66

trek_dan wrote:

The easy answer is to change your 46 chainring to a 50 or 52. Look for a 5x110 10 speed outer chainring, any brand will do ie Shimano/SRAM. All you'll need to do is move your front derailleur up a little.
Although at 46-12 with a cadence of 90rpm you'll be doing 28mph, are you sure you need a bigger top gear?

That's a good question. I have a 46/36 CX chainset with a 12-27 cassette on my winter road bike and rarely spin out. No big / long downhills round here though...

As a result I now have a standard Tiagra 4500 double chainset I don't need. 52/39 I think. Thought about selling it but I think the cost of shipping may exceed the value of the thing. Think I'll keep it as a spare for my son. He's built like a tank and his current Strava obsession may mean his current FSA cheese based chainset doesn't last too much longer...

tgotb

As others said, replace the 46 with a 50.

Or just learn to pedal faster. 46x12 gives you a top gearing of 103". By comparison, most track riders start with a gearing of ~86", and that seems to get them up to 35mph quite happily.

My 3PCX bike has a 34T single ring, which seems good enough for 30mph. I tried spinning out 50x12 on my road bike yesterday (downhill) and consistently bottled at 70kph (~45mph). You're probably braver than me (most people are) but do you really need to get serious power down at that sort of speed?

Bear in mind: A lot of the pros have a top gear of around 52x12, or ~117". If that's good enough for banging along in a pro peloton, getting towed along by the best riders in the World, ~100" should be fine for us mere mortals. That still allows you to reach 85% of the speed the pros are doing. If you're consistently going faster than that, on a CX bike, and without a pro peloton to tow you along, you might want to give Mr Brailsford a call...