Campy 11-speed Frankensprocket 11-29

rjkflyer
rjkflyer Posts: 102
edited September 2012 in Workshop
Hi Guys,

I've got a bike on order with Chorus 12-29 on a compact 50/34 (as I'm a feeble newbie).

Trawling the Campy parts data seems to suggest one could make an 11-29 from either an 11-2x AND my 12-29 (expensive solution), or maybe much more economically buying the parts separately. (i.e. CS-111, 11S-011, 11S-022).

Anyone done this?

Thanks!

Comments

  • Monty Dog
    Monty Dog Posts: 20,614
    Once you get above 70kph on a descent, which is achievable on 50x12, the need for an 11 sprocket is pretty well redundant as maintaining speed is often more about maintaining a good tuck. The only times you'll likely need an 11 is full-on sprinting or fast downhills on TTs - the fact that you're running a 29 rear sprocket suggests you're not doing either?
    Make mine an Italian, with Campagnolo on the side..
  • I'd made a few custom cluster combinations for my campag kit (although 10 speed), including a 11-28 using this miche kit.

    It worked really well for me and it allows me to replace individual sprockets rather than the whole set. They were sold by Company Z in England, but I'm not sure if they are still operating?

    BTW Don't allow yourself to be discourage from having a 11/50 combination on a compact chainset especially if your a power rider and don't spin
  • Thanks guys.

    I guess my slight 'worry' is moving from a hybrid with 48/38/28 and 11-34 is that i might be missing some pace with 'only' 50-12. (Hence my desire to look at getting a 50-11). I went for the 30-29 as I'm not yet good enough to climb without some help...

    Given the new roadie will be a lot lighter (6.5kg versus 12kg) then perhaps I should wait and see how i get on before I start messing with the cassette...?
  • yes wait before spending any cash
  • Yes, agree it's definitely prudent to wait - also no point creating something non-standard for my first experience of Campag which could spoil what should be a pretty decent groupset.

    Interestingly, Campag state a maximum tooth difference of 16 for the 11S rear derailleur - odd given that they sell a 12-29 cassette which I'm getting...
  • for the 12-29 caseete and a compact chainset set you need the medium cage mech.

    On the point of gear ratio's. On sunday I hit 38.3mph pedaling on 52/12. I was doing over 110 rpm. 120 rpm seems to be my limit to get meaningful power. Sustaining 43mph (70 kph) with a 50x12 will require a cadance above 130 rpm. Unless you are a track cyclist this is beyond most people and beside peak power output for most people comes between 90 and 120 rpm roughly.

    I find the 11T on my compact essential. when passing 30 mph.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • this calculator will give you some idea of how speed and cadence are linked with your gear selection. I would only need a 50/11 if I rode in a peloton, downhill at 50KPH i am happy to freewheel.
  • Velonutter
    Velonutter Posts: 2,437
    edited September 2012
    for the 12-29 caseete and a compact chainset set you need the medium cage mech.

    On the point of gear ratio's. On sunday I hit 38.3mph pedaling on 52/12. I was doing over 110 rpm. 120 rpm seems to be my limit to get meaningful power. Sustaining 43mph (70 kph) with a 50x12 will require a cadance above 130 rpm. Unless you are a track cyclist this is beyond most people and beside peak power output for most people comes between 90 and 120 rpm roughly.

    I find the 11T on my compact essential. when passing 30 mph.

    Sorry can't agree, I regularly run 12-29 with a 50/34 for rides where big hills abound such as the Wild Wales and Campag say that all 11s will work with a short cage.

    I have even got the 13/29 10s to work perfectly on my Son and Son-laws bikes with Short Cage.

    I have no problem passing with a 50/14 or even a 16 combination at 30mph+, I do spin out a little at 45mph+ with the 50/12 Combination and could do with an 11 then.
  • rolf_f
    rolf_f Posts: 16,015
    FWIW, when I have a tough route planned and dig out the 10 speed 13-29 cassette (as opposed to my normal 11 or 12-25s) - short cage btw! - I rarely find myself missing even the 12 let alone the 11. For me, if the route is tough enough to need the 29, the amount of time that I will be running at that very narrow margin where the 12 or 11 makes a difference is small. Either you are shooting down a steep descent at way over pedalling speeds or you are back on the flat in a lower than 11 gear anyway.

    Besides, the difference between 12 and 13 is less than the improvement I've made in my normal cadence in the last couple of months anyway!
    Sustaining 43mph (70 kph) with a 50x12 will require a cadance above 130 rpm.

    Lol - next time I want to sustain 43 mph on my bike I'll make a point of putting the 11-25 on. It will make all the difference :lol:
    Faster than a tent.......
  • http://www.gear-calculator.com
    sorry this is the gear calculator
  • Monty Dog
    Monty Dog Posts: 20,614
    I'm running 13-29 with a short cage rear no problems

    Is 130 rpm fast? It's when you start getting north of 180rpm on the road it starts getting a bit blurry!
    Make mine an Italian, with Campagnolo on the side..