looking at switching from my compact crank and 11/23 cassette to standard crank. What would be a comparable cassette for the low end clibing gearing to the 34/23 that I have now. would a 39/25 be close or 39/26? i need a bit more top end speed but am not the best climber and like to spin vs power up climbs. Only looking to switch for better sprinting gears.