Gear Help

Markjaspi

I'm currently changing my group set from Sora to 105, the only parts left to be purchased are the crankset, shifters (double) & cassette.

My current setup is a Compact 50/34 with a 12-27 cassette (9 speed) but to be honest I never have to use the lower cog as its not particularly hilly where I am, not that I won't be hitting hills in the future.

I'm thinking of a more standard 53/39 with 11-25 set up, my average cadence is around 80rpm, I can go higher but seem to settle well at this speed and usually average around 18.8 to 19.8 mph on rides 20-40 miles long.

Can the more experienced give me their thoughts? Would the change in setup benefit? Or should I stick with the same gearing?

Thx in Advance.

smidsy

Your proposing a double whammy with that as you are increasing the front chainrings AND reducing the rear cassette.

If you do get to any reasonable hill can you push up it with 39/25? Its quite a jump from your current 34/27.

Markjaspi

To be honest I'm not entirely sure, I could air on caution and get a standard double and 11-28 cassette or vice versa I suppose. Whilst I was away this year in Settle I tackled a couple of big hills on my hybrid I owned at the time, with out the need to go too far down the back cog whilst on the lower front.

Although to be honest I don't know what gear ratio that cassette was, but I'm guessing it would have had a lower bottom gearing.

I suppose the question is (as cassettes are relatively cheap) would it make sense to get a standard crankset and then I could alter the rear cassette or just stick with a 50/34 just in case and then alter the rear cassette to suite.

smidsy

Looking at it another way do you spin out regularly with 50/12 or struggle to find a nice sustainable gear at your preffered cadence ?

If not why do you need anything different?

sjacob33

Just my 2 bob i would get the 28 at the rear better to have that there and have to switch up then getting to the bottom and having nowhere to go. If you do find it too easy replacing a cassette with a 25 or 23 (or even just change out that sproket) is much much cheaper and easier than a crank set.

Markjaspi

I see what you are both saying, I don't struggle to find a gear to settle at with my preferred cadence, however if I do have one of those bursts where I feel the need to ramp up over 90rpm+ I can spin out at 50/12.

I also see the sense in the 28, as at least it's there if you should need it , I would hate to struggle up a hill and regret having changed it.

I suppose whilst I'm changing the set up any way, I just wanted to explore all avenues, would a standard crank with a 11-28 be a half way house so to speak?

NewTTer

I doubt that you have ever spun out on a 50 - 12. What speed did you achieve when you did this, I ask as then this will give a true indication of your cadence, and then to give a more realistic answer to your gearing question

Markjaspi

Hi, pretty sure I have a couple of times, on one particularly down sloping section of the route I run, where you need to move as quick as possible to avoid traffic if the situation allows. But it's not very often, didn't want mean to make out this was a regularly occurrence and I'm some sort of super hero.

NewTTer

Markjaspi wrote:

Hi, pretty sure I have a couple of times, on one particularly down sloping section of the route I run, where you need to move as quick as possible to avoid traffic if the situation allows. But it's not very often, didn't want mean to make out this was a regularly occurrence and I'm some sort of super hero.

So have you spun it out or not? and what sort of mph did you achieve whilst doing this, also what sort of cadence do you consider to be spinning out?