Cassette change advice: Canyon for hill work

errecaldia
errecaldia Posts: 41
edited April 2019 in Workshop
I have a Canyon CF SL 8 Disc with Shimano Ultegra R8000 11-32 11s cassette and Ultegra FC R8000 11s chainring 52 - 36.

I would like to achieve a lower bottom ratio than 32 /36 for hill climbing: where I live most decent rides have several km at 15% and short stretches at 20%. With two prolapsed lumbar discs, I need to reduce the challenge! But I like the fast top ratio and i like the smooth gear changing. Is there a chnage I could make that would extend the ratios while still giving a nice, smooth change?

Louise

Comments

  • arlowood
    arlowood Posts: 2,561
    Errecaldia wrote:
    I have a Canyon CF SL 8 Disc with Shimano Ultegra R8000 11-32 11s cassette and Ultegra FC R8000 11s chainring 52 - 36.

    I would like to achieve a lower bottom ratio than 32 /36 for hill climbing: where I live most decent rides have several km at 15% and short stretches at 20%. With two prolapsed lumbar discs, I need to reduce the challenge! But I like the fast top ratio and i like the smooth gear changing. Is there a chnage I could make that would extend the ratios while still giving a nice, smooth change?

    Louise

    Depends how much you are prepared to spend. If your current rear derailleur is a medium cage then you could fit an Ultegra 11-34 cassette which will extend your gearing a bit.

    https://www.chainreactioncycles.com/shi ... prod161362

    You also have the option to switch to a compact (50/34) chainset so would end up with a 1:1 lowest gear. However that would mean spending a chunk of cash - although you could recoup some funds by selling off the 11-32 cassette, short cage mech (if you have to replace it) and semi-compact chainset
  • Alejandrosdog
    Alejandrosdog Posts: 1,975
    arlowood wrote:
    Errecaldia wrote:
    I have a Canyon CF SL 8 Disc with Shimano Ultegra R8000 11-32 11s cassette and Ultegra FC R8000 11s chainring 52 - 36.

    I would like to achieve a lower bottom ratio than 32 /36 for hill climbing: where I live most decent rides have several km at 15% and short stretches at 20%. With two prolapsed lumbar discs, I need to reduce the challenge! But I like the fast top ratio and i like the smooth gear changing. Is there a chnage I could make that would extend the ratios while still giving a nice, smooth change?

    Louise

    Depends how much you are prepared to spend. If your current rear derailleur is a medium cage then you could fit an Ultegra 11-34 cassette which will extend your gearing a bit.

    https://www.chainreactioncycles.com/shi ... prod161362

    You also have the option to switch to a compact (50/34) chainset so would end up with a 1:1 lowest gear. However that would mean spending a chunk of cash - although you could recoup some funds by selling off the 11-32 cassette, short cage mech (if you have to replace it) and semi-compact chainset

    Can’t she just get chainrings?
  • manglier
    manglier Posts: 1,208
    No, the BCD on a semi-compact is 130mm and will noit accept compact chainrings (110mm).
  • paulbnix
    paulbnix Posts: 631
    I recently bought an Ultegra 11-34 cassette to use sometimes in place of an 11-32 SRAM.
    I find that while it gives better ratio steps at the the big end it is not as good at the small end.
    The 2 tooth intervals give to big a jump for comfort.
    SRAM 11,12,13,14,15,17,19,22,25,28,32
    Ultegra 11-13-15-17-19-21-23-25-27-30-34
  • Alejandrosdog
    Alejandrosdog Posts: 1,975
    Manglier wrote:
    No, the BCD on a semi-compact is 130mm and will noit accept compact chainrings (110mm).
    I believe the new style chain sets are using 110 bcd for everything. (I may be wrong)
  • munkster
    munkster Posts: 819
    I believe that is the case too. However, with a new chainring apparently costing over £100 (unless my quick google has missed an obvious cheap source!) I might be tempted by the full chainset option personally, it'd be easier to flog on eBay than a chainring IME! YMMV etc etc.
  • I'm afraid I don't understand the thread :( I don't have this kind of knowledge of kit, I just ride it! (Not a hopeless female, though, talk to me about the Triumph Stag recently restored....)

    Louise
  • imposter2.0
    imposter2.0 Posts: 12,028
    Manglier wrote:
    No, the BCD on a semi-compact is 130mm and will noit accept compact chainrings (110mm).
    I believe the new style chain sets are using 110 bcd for everything. (I may be wrong)

    ^^ this. (you're not wrong)
  • keef66
    keef66 Posts: 13,123
    Bigger sprocket at the back and smaller chainrings at the front are both ways to achieve easier climbing gears. You can do both.

    Expensive job replacing chainrings on an ultegra chainset though
  • keef66
    keef66 Posts: 13,123
    If you can restore a Stag I'm sure you can change the gearing on a road bike.

    If you need to keep costs down buy a second hand 11 speed 105 chainset with 50/34 rings, and fit an 11-34 cassette.

    Dearer option is new rings for the Ultegra chainset, or a completely new 50/34 R8000 one. easy to fit
  • keef66 wrote:
    If you can restore a Stag I'm sure you can change the gearing on a road bike.

    If you need to keep costs down buy a second hand 11 speed 105 chainset with 50/34 rings, and fit an 11-34 cassette.

    Dearer option is new rings for the Ultegra chainset, or a completely new 50/34 R8000 one. easy to fit

    *grins* yes, I can change them, the bits I don't understand are about compatibility. I worked out what bcd is ;) But cage lengths and the effects changing gears has on cage length and chain length isn't easy to find out.

    Is an 11 - 34 cassette with a 34 chain ring, but keeping the 52 chain ring, possible? And if so, what is the consequence on cage and chain lengths?
  • mrb123
    mrb123 Posts: 4,569
    I believe that the maximum difference between the front chainrings should be 16 teeth, so 50:34 is ok, as is 52:36, but not 52:34.


    50/11 is still a very big gear so don't worry about losing out at the top end too much.
  • kajjal
    kajjal Posts: 3,380
    Have a read of this, it explains how to chose the correct size rear derailleur for different gear combinations as well.

    https://road.cc/content/feature/213519- ... es-how-get
  • svetty
    svetty Posts: 1,904
    If you already have a 32 as your largest sprocket you should be able to fit an 11-34 cassette OK. Might need to adjust the B screw but it should work OK.
    FFS! Harden up and grow a pair :D