bobbyl1966

What cassette is ideal for this two cranks 53/39 and 52/42 the best is tight cassette ratio or wide cassette? terrain is flat but hilly too.

Homebrew01

Personal preference. Based on your fitness, terrain, style of riding....
If you don't like your choice of gears, they are easy to change.

MikeWMass

I would choose a cassette that is tight but wide too.

bobbyl1966

like example in 9 speeds cassette 12-27? Is between 12-23 and 12-32. I have used 12-25 is have came with my used bikes in flats is okay but in hills i need lower gear. i do want put in my bike 12-23 i do like the close ratio but in hills is go be too hard to pedal. 12-25 cassette i have used with 53/39 crank. I dont not know if i can make crank 53/36 or 53/34

GeoKrpan

There is really not much difference between the two if you compare the gear inches with the same cassette.

bobbyl1966

Because i want use in my bikes 12-23 cassette and i ride not in flat trail only most i ride in hilly trail elevation is from 700 feet to 900 feet. The 23 cog lowest gear ratio is give me 44.6" That ratio is looks is to high for the hills? I not know with the 23 cog but with 25 cog and 39 chainring i stay seated and pedal all the way up in the hills but my speed is slow down much is happens time i have to walk in hill i deside do that get of the bike and walk uphill is not worth i pedal and i go slower than i can walk uphill.

Homebrew01

Better to have gears that are too easy. Get the lowest gear you need.

You have about 5 threads on this topic. It's getting a bit silly to keep asking random people on the internet what gears you should get.

Let your legs tell you.

fietsbob

Sheldon Brown's Bicycle Gear Calculator to help with the math

Drew Eckhardt 

IMHO, cassettes with one tooth jumps through the 19 cog are the only ones suited to road riding on flat terrain.

12-19/13-21 8 cogs, 11-19/12-21/13-23/14-25 9 cogs, 11-21/12-23/13-25/13-26/14-28 10 cogs, 11-23/12-25 11 cogs.

If you're not going to change cogs for climbing rides pick the low gear you need and settle for the small cog which results. Even 53x14 is a 40+ MPH sprinting gear.

If you can't get a low enough gear switch to a triple crank. The 52/42 is probably old enough to have a square taper bottom bracket, so you can get a longer one and run a tripleizer middle ring.

andr0id

Over the years I've ridden 10/12/14 speed with 52/42 which was the standard crank back then.

Then 53/39 for 9 and 10 speed.

I've used 42/54 on my TT bike, but 42 isn't that great unless your on only flat or rolling terrain. If you're having to come out of low water crossing into the wind, the 42 will get the job done.

While the standard compact is 50/34 and the mid-compact is 52/36, I actually like 50/36 with a 11-23 or 11-25. It gets me a decent high and low range with no gaps on the 11-23 or only 1 gap on the 11-25.

Bridrider

Why do you consider having tighter cog spacing more important than top end speed? I'd never be caught dead in a RR with anything less than a 53-11 for descending you can spin that gear up and get super tucked to go really fast.

Next what's wrong with modern spacing on something like a 11spd 11-32 cassette? I've rarely found that I need a gear in between for road riding. I love having the ability to climb with the 32 (especially up hill in the wind).

Bridrider

And I agree that having a tight range for TT is more important but it doesn't sound like that's what he's using it for.

Homebrew01

I've done dozens of road races and never needed a 53x11. Depends on your terrain.

Generally a tight tuck is better at top downhill speeds, since you spend no energy.

Regardless, OP should get the gearing he needs, not the gearing the rest of us need.

andr0id

I find gaps to be most annoying 3 or more hours into a ride. I'm spinning just a bit, click up and now I'm pushing harder than I want. Look back and sure enough, it's always the 19-17 split.

I get more cadence sensitive as I get a little tired. Start of a ride, 80-110 is all fine. End of a ride with a lot of climbing and I want to be 90-100.