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Old 09-24-12, 01:46 PM
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Andy_K 
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Head tube angle has negligible effect on perceived top tube length. Seat tube angle does have an effect, but I think you have it backward. A 1 degree steeper seat tube angle effectively lengthens the top tube by about 1 cm because you have to move the seat back to get the same position relative to the bottom bracket. You didn't say what year Major Jake you have, but it looks like the 56cm in recent MJ's have a 73.7 degree seat tube angle, whereas the 54cm X-Ride has a 73 degree seat tube angle.

The biggest difference I see between the Ridley geometry and the Kona geometry is that Ridley favors a taller head tube for the same top tube length. The taller head tube also makes the reach to the bars feel shorter, though it's more difficult to quantify and more dependent on arm length than the seat tube angle effect.

The 'reach' measurement in the geometry is meant to give a seat-tube angle independent measure of how far the bars are from the saddle. The 56cm Major Jake and the 56cm X-Fire have the same reach. Stack (bb to head tube top difference) is about 20mm larger on the X-Fire. That's not a huge difference.

I'm 5'9" and ride a 54cm Major Jake (fits like the current 53). If I were going to buy and X-Ride, I'd be torn between the 54 and the 56, probably choosing the 54 for standover clearance.

I think 56 is probably the best bet for you.
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