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Gear ratio advice required.

moyesiemoyesie Posts: 68
edited June 2015 in Road general
Evening All :)

Currently a major 'first world issue' in that I can't decide what cassette to fit next.

ATM I'm running a Campag 11spd 11-25 cassette with a 50/34 up front.

Being a bigger lad with access to that Dales & Moors of Yorkshire this mostly suits me, I can still get myself up the likes of Boltby, Buttertubs etc.

It's time to change cassette and being honest I fancy the 11-27; however with this combo I'd lose the 16t which now I'm conscious of it, would no doubt always bug me!

Going 12-27 would let me keep the 16t but I REALLY want to keep the 11t as I'd hate to lose it for the downhill.

The way I see it I have the following options:

1. Keep the 11-25 and struggle up the hills

2. Replace with 11-27 or even 11-29 and suck up the missing 16t.

3. Run two cassettes, 11-23 and 11-29 but have the added FAF of swapping chains and cassettes.

Interested to hear opinions, I'm thinking the 11-27 makes the most sense.
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Posts

  • AnonymousAnonymous Posts: 28,799
    How much do you push on downhills? spinning a 50x12 at 130 rpm (so spinning out basically) will take you to 70Kph and the same on a 50x11 will be 74 Kph, so you are losing 4 Kph at spin out in your biggest gear.

    Heres the comparison from 30 RPM to 130 RPM:

    50x11 17.29 23.05 28.82 34.58 40.34 46.11 51.87 57.63 63.40 69.16 74.92

    50x12 15.85 21.13 26.41 31.69 36.97 42.26 47.54 52.82 58.10 63.39 68.67

    I don't think you really need a 11 tooth (even for descents) in the UK unless you are very fit/pro. Especially considering you are on open roads.
  • HebdenBikerHebdenBiker Posts: 787
    I've had lots of different cassettes, but I've never "missed" any particular sprocket from the middle of the range :-) I reckon you'll get used to the change.

    I'd go for the 11-27 if I were you, keeping the 11. I push hard on descents but can't get beyond 46-47mph. I'd need an 11 to go over 50mph.
  • trailflowtrailflow Posts: 1,311
    Buy the 12-27t and keep the 16.

    Then swap the 12t cog with your old 11t cog.
  • FatTedFatTed Posts: 1,214
    12-27 I doubt you will miss the 11 speed cog.
  • bernithebikerbernithebiker Posts: 4,148
    sjmclean wrote:
    How much do you push on downhills? spinning a 50x12 at 130 rpm (so spinning out basically) will take you to 70Kph and the same on a 50x11 will be 74 Kph, so you are losing 4 Kph at spin out in your biggest gear.

    Heres the comparison from 30 RPM to 130 RPM:

    50x11 17.29 23.05 28.82 34.58 40.34 46.11 51.87 57.63 63.40 69.16 74.92

    50x12 15.85 21.13 26.41 31.69 36.97 42.26 47.54 52.82 58.10 63.39 68.67

    I don't think you really need a 11 tooth (even for descents) in the UK unless you are very fit/pro. Especially considering you are on open roads.

    130 cadence is extremely fast, and I doubt many here can sustain that, especially when on the drops in a downhill tuck.

    Surely 100 is a more realistic (though still quite high) figure?

    I have spun out my 50-11 many a time on long Alpine descents, and would no way go to a 12.

    For the OP, I use a 23-11 for Brittany (quite hilly, but no really long hills), and swap to a 27-11 for Alps/Pyrenees. I don't have to adjust my chain.
  • sjmclean wrote:
    How much do you push on downhills? spinning a 50x12 at 130 rpm (so spinning out basically) will take you to 70Kph and the same on a 50x11 will be 74 Kph, so you are losing 4 Kph at spin out in your biggest gear.

    Heres the comparison from 30 RPM to 130 RPM:

    50x11 17.29 23.05 28.82 34.58 40.34 46.11 51.87 57.63 63.40 69.16 74.92

    50x12 15.85 21.13 26.41 31.69 36.97 42.26 47.54 52.82 58.10 63.39 68.67

    I don't think you really need a 11 tooth (even for descents) in the UK unless you are very fit/pro. Especially considering you are on open roads.

    Agreed, for most people when going downhill nearly all the power is coming from the gradient, not peddling. you'd probably go faster by getting more aero compared to peddling. By a rough back of the envelope calc 70kph on a gradient of 10% gives you 1526W from gravity (bike+rider 80kg, according to online power calculators 70kph is around 1450W so about right). Personally I can't get near that power at steady state so tucking down more, concentrating on line and saving energy for the uphills is probably better.

    Also remember that power goes as speed cubed, so 15% extra power (230W in the above scenario) will give you less than 5% extra speed. All in all I'd go for the 12 tooth min and get the benefit from the closer ratios where you can actually gain significant time.
  • DebeliDebeli Posts: 637
    I'd be inclined to shut my eyes and put a pin in a list of ratios.

    You will not be disappointed, wherever the pin ends up.

    I'd agree with the poster who said you wouldn't miss a middle-of-the-cassette ratio.

    Many of us have seen the increase of cassettes over the years from five to six, seven, eight ratios and on up to eleven. My own cassettes have never got past ten, but that is still a fairly funky choice of gears.

    I'd choose by maxima and minima, not what lies between. Sprocket sizes are so close these days (on road bikes) that the difference would hardly be perceptible. The cycling press may tell you otherwise, but your legs don't read the cycling press.

    As to descending, I do like a fairly long ratio for those fast-but-not-too-fast descents where whipping the pedals round can make a difference. My tallest is 53/11 and it lets me spin at 130-135 rpm on short hills to give me a nice low-to-mid 40s mph. On those same hills, shorter top ratios can frustrate just a teeny bit.

    Go for low/high. Ignore the stuff in the middle.
  • I'm a fan of 12-28, gives an even gap between ratios, very rarely get to the 28, but it's nice to know it's there!

    Yes you may sometimes spin out. Unless you're on closed roads or pointing down a really big hill, how often is that a problem? I just draft someone & then the issue's disappeared.....

    It's better to have the ratios that work for you, getting up the hill is the bit that makes the ride quicker.
  • dyrlacdyrlac Posts: 735
    Agree with (some of) the above. You won't miss an individual mid-cassette sprocket, and I worry we fetishize close ratios. But I am by no means a spinnimist: sometimes I just like to stomp on a gear with some bite, and rarely get worked up about cadence.
  • davep1davep1 Posts: 725
    My old bike was Campag 9 speed, 53-39 up front, and initially 12-25 at the back. I live near Brighton, and although I could get up all the hills around me, I noticed if I rode with anyone with a compact they would always pull away from me and the longer the climb went on the further away they would go. They would also be sat down and putting in less apparent effort; whilst I admire Pantani's style and am not averse to long periods dancing on the pedals, I knew it wasn't the clever way.
    When that cassette wore out, I went 12-27 and noticed a benefit, and again when that one wore, I went 12-29 and again noticed a difference. I couldn't get a cassette with an 11 tooth option, they were all closer ratio ones.
    I would go for the 11-27 in your shoes, I think the 11 is important especially with a compact, and you will see a benefit with the 27. There are always gaps in cassettes, you just have to work round it, but you'll get the benefit of the top and bottom.
  • ai_1ai_1 Posts: 3,060
    sjmclean wrote:
    How much do you push on downhills? spinning a 50x12 at 130 rpm (so spinning out basically) will take you to 70Kph and the same on a 50x11 will be 74 Kph, so you are losing 4 Kph at spin out in your biggest gear.

    Heres the comparison from 30 RPM to 130 RPM:

    50x11 17.29 23.05 28.82 34.58 40.34 46.11 51.87 57.63 63.40 69.16 74.92

    50x12 15.85 21.13 26.41 31.69 36.97 42.26 47.54 52.82 58.10 63.39 68.67

    I don't think you really need a 11 tooth (even for descents) in the UK unless you are very fit/pro. Especially considering you are on open roads.

    130 cadence is extremely fast, and I doubt many here can sustain that, especially when on the drops in a downhill tuck.

    Surely 100 is a more realistic (though still quite high) figure?

    I have spun out my 50-11 many a time on long Alpine descents, and would no way go to a 12.

    For the OP, I use a 23-11 for Brittany (quite hilly, but no really long hills), and swap to a 27-11 for Alps/Pyrenees. I don't have to adjust my chain.
    I don't think 100 is realistic as an upper limit when pushing hard. I think most people can easily exceed and sustain this while cruising never mind for brief periods on a descent. I've descended at 80km/h+ while applying power on 50/12 which would be in excess of 150rpm based sjmclean's figures. I've seen 160rpm+ on one or two occasions and I doubt very much I'm at the fastest spinning end of the spectrum (I have big fat calves which can't help!). Not saying these are typical cadences obviously. I tend to average in the mid-80s most of the time.
  • AnonymousAnonymous Posts: 28,799
    130 cadence is extremely fast, and I doubt many here can sustain that, especially when on the drops in a downhill tuck.

    Surely 100 is a more realistic (though still quite high) figure?

    I have spun out my 50-11 many a time on long Alpine descents, and would no way go to a 12.

    For the OP, I use a 23-11 for Brittany (quite hilly, but no really long hills), and swap to a 27-11 for Alps/Pyrenees. I don't have to adjust my chain.

    That's alpine descents, that what I said basically, in the Uk it will be different.

    In terms of cadence my normal group road riding see's me hold an average cadence between 95-105 on the flat and 70ish on the hills.
  • moyesiemoyesie Posts: 68
    Thanks for all the replies :)

    One thing I do know is that I need the 11t. When it comes to descending I am on the 'enthusiastic' side and do not hold back, I've had a 12t in the past and missed the 11t, this was also confirmed on a recent descent of Teide where the 52/12 just wasn't enough (52/12 is lower than 50/11).

    So now I need to decide on 27 or 29t!

    I did notice with a move to a 28t on the winter bike my climbing didn't improve, my cadence on 28t stayed the same as 25t with the added 'bonus' of being slower!


    I
  • meanredspidermeanredspider Posts: 12,550
    I too like my 11-tooth but I also go up some 20% gradients. I've come at this problem in a slightly different way and fitted a 33-ring up front - thus spreading the high and low gears out that bit further.
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • First.AspectFirst.Aspect Posts: 3,388
    I've had lots of different cassettes, but I've never "missed" any particular sprocket from the middle of the range :-) I reckon you'll get used to the change.

    I'd go for the 11-27 if I were you, keeping the 11. I push hard on descents but can't get beyond 46-47mph. I'd need an 11 to go over 50mph.
    This. You won't notice that the 16T is missing. People used to mange with 9 speed you know :shock:
  • Simon MastersonSimon Masterson Posts: 2,740
    I think it's best to look at this in terms of cadence, speed , and the roads you're riding on. If 80-120rpm is a normal cadence range, I would say that up to about 150rpm is reasonably attainable for a short burst - not a leg speed you'd want to be doing for an hour in the alps, but we don't have (m)any descents like that in this country anyway. 50x12 will get you up to about 40mph well within that range, and more like 50mph at the very top. If the descent is even vaguely steep, you should be able to get up over 40mph without pedalling, and if you can't, your position isn't up to snuff.

    Based on the above assessment, I would definitely dispute that you need an 11t cog, purely because I imagine that the descending that you're doing could be done at the same speed without pedalling, and/or the descents are short enough to raise your cadence, and I also assume that you might not be within the 130-150rpm range when you spin out, and therefore you could benefit from improving your leg speed. Nothing wrong with having it if you want it, but I think I personally would prioritise the low gears. YMMV.
  • meanredspidermeanredspider Posts: 12,550
    Where I find the 11T helps isn't in spinning like a lunatic but in getting up to speed quickly at the top of a climb. Anybody that's looked at power figures going down a hill will know that it's hard to generate big numbers because you're chasing the pedals as gravity gets onboard. Having a big gear to push at the top of a climb (or, in the Alps, coming out of a hairpin) enables you to input a large chunk of power and get up to speed earlier. You then carry that speed all the way down. I like it. It isn't essential but it's nice
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • bernithebikerbernithebiker Posts: 4,148
    When riding something like the Etape as quicky as possible, the last thing I want to be doing is pedalling like a crazy when on the downhills. I also find it harder to hit v.high cadences (above 120) when in the drops.

    An 11t allows you to go into 'overdrive', reduce cadence, relax, and recover for the next ascent.
  • moyesie wrote:
    Thanks for all the replies :)

    One thing I do know is that I need the 11t. When it comes to descending I am on the 'enthusiastic' side and do not hold back, I've had a 12t in the past and missed the 11t, this was also confirmed on a recent descent of Teide where the 52/12 just wasn't enough (52/12 is lower than 50/11).

    So now I need to decide on 27 or 29t!

    I did notice with a move to a 28t on the winter bike my climbing didn't improve, my cadence on 28t stayed the same as 25t with the added 'bonus' of being slower!


    I

    You'd seriously be better off without the 11 and gain a sprocket mid-block. Learn to pedal and the 12 will be plenty. 50/11 is bigger than 53/12 which is what most decent amateur riders use. Sean Kelly used to ride 52/12 and he was possibly stronger than you are? Whatever you think you are gaining by sticking with an 11 you are losing more by not having a more suitable gear in the middle of the block. Not learning to pedal is the biggest mistake people can make.
  • LookyhereLookyhere Posts: 987
    i think the 11t is a waste of time, pedalling like crazy down a steep alpine descent might seem fast but in reality, gravity is what is taking you down the hill quickly, that and going super fast round the corners and accelerating quickly back up to speed again, get aero and fly past slower riders with their 11t.
    ...and i was far stronger than that kelly chap, what did he ever win :lol:
  • bernithebikerbernithebiker Posts: 4,148
    moyesie wrote:
    Thanks for all the replies :)

    One thing I do know is that I need the 11t. When it comes to descending I am on the 'enthusiastic' side and do not hold back, I've had a 12t in the past and missed the 11t, this was also confirmed on a recent descent of Teide where the 52/12 just wasn't enough (52/12 is lower than 50/11).

    So now I need to decide on 27 or 29t!

    I did notice with a move to a 28t on the winter bike my climbing didn't improve, my cadence on 28t stayed the same as 25t with the added 'bonus' of being slower!


    I

    You'd seriously be better off without the 11 and gain a sprocket mid-block. Learn to pedal and the 12 will be plenty. 50/11 is bigger than 53/12 which is what most decent amateur riders use. Sean Kelly used to ride 52/12 and he was possibly stronger than you are? Whatever you think you are gaining by sticking with an 11 you are losing more by not having a more suitable gear in the middle of the block. Not learning to pedal is the biggest mistake people can make.

    You are advocating very high cadence here, yet suggesting it's a good idea to ride up Sa Calobra in the big ring in another post (I'm assuming you can't climb Sa Calobra in 53-23 at much more than 70 cadence or you'd be in the top 25 on Strava, (20.5km/h).

    Clearly I am not as strong as Sean Kelly, so would prefer to take my cadence down a notch on the descents to preserve energy for the next climb.

    The difference in a DA9000 11-28 and a 12-28 is a 16t sprocket. Not such a big deal.
  • drlodgedrlodge Posts: 4,824
    I had 34-50 and 12-27, changed the cassette for the 12-29 last year before doing the Dales and its the best equipment change I've ever done.
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • paul2718paul2718 Posts: 471
    I miss the 16. And I use the 11 or 12 quite often on slight down-hills or down wind stretches. The fact that I can pedal at more than 110rpm doesn't mean I want to.

    Choices...

    Paul
  • moyesie wrote:
    Thanks for all the replies :)

    One thing I do know is that I need the 11t. When it comes to descending I am on the 'enthusiastic' side and do not hold back, I've had a 12t in the past and missed the 11t, this was also confirmed on a recent descent of Teide where the 52/12 just wasn't enough (52/12 is lower than 50/11).

    So now I need to decide on 27 or 29t!

    I did notice with a move to a 28t on the winter bike my climbing didn't improve, my cadence on 28t stayed the same as 25t with the added 'bonus' of being slower!


    I

    You'd seriously be better off without the 11 and gain a sprocket mid-block. Learn to pedal and the 12 will be plenty. 50/11 is bigger than 53/12 which is what most decent amateur riders use. Sean Kelly used to ride 52/12 and he was possibly stronger than you are? Whatever you think you are gaining by sticking with an 11 you are losing more by not having a more suitable gear in the middle of the block. Not learning to pedal is the biggest mistake people can make.

    You are advocating very high cadence here, yet suggesting it's a good idea to ride up Sa Calobra in the big ring in another post (I'm assuming you can't climb Sa Calobra in 53-23 at much more than 70 cadence or you'd be in the top 25 on Strava, (20.5km/h).

    Clearly I am not as strong as Sean Kelly, so would prefer to take my cadence down a notch on the descents to preserve energy for the next climb.

    The difference in a DA9000 11-28 and a 12-28 is a 16t sprocket. Not such a big deal.

    You won't be saving energy using an 11, you'd get more benefit retaining the 16. If you are strong enough to push the 11 then maybe you shouldn't be using a 27.

    As for suggesting it is a good idea to ride up Sa Calobra in the 23. Perhaps you could point me towards that post. Thanks.
  • bernithebikerbernithebiker Posts: 4,148

    You won't be saving energy using an 11, you'd get more benefit retaining the 16. If you are strong enough to push the 11 then maybe you shouldn't be using a 27.

    As for suggesting it is a good idea to ride up Sa Calobra in the 23. Perhaps you could point me towards that post. Thanks.


    These are your words I believe;

    Something else. Both those are comfortably big ring climbs. There are some real tough climbs there, you'l just need to find them!

    So presumably, if you're comfortable it must be a good idea, right?

    I disagree re. saving energy. I've just been spinning at 100+ for an hour or so up the Tourmalet, and I'm taking on Peyresourde next. I want to descent reasonably quickly, but without pushing myself hard, and not spinning like a madman. Therefore some aero descending, with some lower cadence, low power pedalling to keep speed up a bit, works fairly well for me.

  • You won't be saving energy using an 11, you'd get more benefit retaining the 16. If you are strong enough to push the 11 then maybe you shouldn't be using a 27.

    As for suggesting it is a good idea to ride up Sa Calobra in the 23. Perhaps you could point me towards that post. Thanks.


    These are your words I believe;

    Something else. Both those are comfortably big ring climbs. There are some real tough climbs there, you'l just need to find them!

    So presumably, if you're comfortable it must be a good idea, right?

    I disagree re. saving energy. I've just been spinning at 100+ for an hour or so up the Tourmalet, and I'm taking on Peyresourde next. I want to descent reasonably quickly, but without pushing myself hard, and not spinning like a madman. Therefore some aero descending, with some lower cadence, low power pedalling to keep speed up a bit, works fairly well for me.

    You presume wrong.

    Riding a big gear tires the legs out. You might convince yourself that you need an 11 and good luck to you but if you indeed are strong enough to push one, why on earth ride a 27 on the hills? I'm not going to argue, just passing on some advice. Just because bikes come equipped with an 11 doesn't mean that you need to use it.
  • bernithebikerbernithebiker Posts: 4,148

    You won't be saving energy using an 11, you'd get more benefit retaining the 16. If you are strong enough to push the 11 then maybe you shouldn't be using a 27.

    As for suggesting it is a good idea to ride up Sa Calobra in the 23. Perhaps you could point me towards that post. Thanks.


    These are your words I believe;

    Something else. Both those are comfortably big ring climbs. There are some real tough climbs there, you'l just need to find them!

    So presumably, if you're comfortable it must be a good idea, right?

    I disagree re. saving energy. I've just been spinning at 100+ for an hour or so up the Tourmalet, and I'm taking on Peyresourde next. I want to descent reasonably quickly, but without pushing myself hard, and not spinning like a madman. Therefore some aero descending, with some lower cadence, low power pedalling to keep speed up a bit, works fairly well for me.

    You presume wrong.

    Riding a big gear tires the legs out. You might convince yourself that you need an 11 and good luck to you but if you indeed are strong enough to push one, why on earth ride a 27 on the hills? I'm not going to argue, just passing on some advice. Just because bikes come equipped with an 11 doesn't mean that you need to use it.

    If someone said to me, "Know anything about Sa Calobra?" and I replied, "that's a comfortable big ring climb that", then I think the questioner could reasonably assume that I would be climbing it in the big ring, with relative ease (and comfort?), and that he could probably do the same. Which is misleading, to say the least.

    I'll keep my 11 thanks, as I've never said to myself, 'Goddamm it, where the hell is that 16 that I need?'. It doesn't mean I'm strong, fast or weak, it just means I can keep the cadence at reasonable levels when descending fast.
  • LookyhereLookyhere Posts: 987
    I disagree re. saving energy. I've just been spinning at 100+ for an hour or so up the Tourmalet, and I'm taking on Peyresourde next. I want to descent reasonably quickly, but without pushing myself hard, and not spinning like a madman. Therefore some aero descending, with some lower cadence, low power pedalling to keep speed up a bit, works fairly well for me.

    Hold a 100 + rpm, on your 34/28, for an hour, up the Tourmalent (a Strava HC?) thats over 15kph and your in the top 10 for the Strava segment, thats cool 8)
  • meanredspidermeanredspider Posts: 12,550
    Anybody that claims to know what gears are "right" for another person is misguided. Climbing, in particular, is incredibly personal: standing, seated, mashing, spinning - there's no "right" answer for everyone. If I don't have an 11T I miss it if it's hilly. In NL I ride12-23 on a std double. I couldn't, on the other hand, tell you what mid-range gears I have on my wider-range cassettes - the steps don't bother me provided I've got something short enough for the climbs and ride I'm doing.
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • bernithebikerbernithebiker Posts: 4,148
    Lookyhere wrote:
    I disagree re. saving energy. I've just been spinning at 100+ for an hour or so up the Tourmalet, and I'm taking on Peyresourde next. I want to descent reasonably quickly, but without pushing myself hard, and not spinning like a madman. Therefore some aero descending, with some lower cadence, low power pedalling to keep speed up a bit, works fairly well for me.

    Hold a 100 + rpm, on your 34/28, for an hour, up the Tourmalent (a Strava HC?) thats over 15kph and your in the top 10 for the Strava segment, thats cool 8)

    Jesus, it's just to give a rough idea - I was 'spinning' as best I could, and yes, in the 34-28. Strava has me at between 12 and 13kph, so 80+ cadence then. Happy?
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