Climbing Steep (25%+) Hills on road bikes

Discussion in 'Cycling Equipment' started by cjhcjh, Oct 14, 2014.

  1. cjhcjh

    cjhcjh New Member

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    Hi All,

    I'm trying to tackle the steepest hill I could find and for the first time ever I couldn't get to the top of a bitumen road. I want this hill, but really think I need to make some gearing adjustments.

    I'd really appreciate some input on which cassettes are possible and whether a new RD would be required.

    I'm running full 105 5700 with compact crankset. currently have 12-17 cassette (apparently the largest/lowest the RD can handle).

    The hill has two steep segments ranging between 22% to 28%. First segment is 22%-28% for ~75m, the second is at 22% to 28% for ~150m or a bit more. It's only about 300m elevation, I managed the first section and about 40% of the second segment, but the drop -off and no railings were getting to me at <40rpm. Oh, and the road has gravel in patches all the way up.

    I know I could get a MTB, but where's the fun in that?

    Yes, I could get stronger. Although I'm a spinner (195cm, 79kg) and am happiest 92-104 rpm, which makes the 27 on the cassette ideal for ~7.5-8% inclines. What that means is that for steep hills, i'm in the same gear from 8% to 28%. So the stronger route would mean a significant amount of specific training, dramatic change in body shape and consist of buying a whole new wardrode... so lets rule that one out.

    I'm after something between getting a bit fitter (that part is easy and already underway), and not replacing the whole bike, but maybe a lowest 30/32/34/36? cassette and possibly a new RD to make that cassette compatible.

    From what I have researched so far:
    Sheldon Brown seems to think the 10s STI and a wide range cassette is possible through either a Deore 9s RD or a new SunXCD RD allowing a cassette with a 34 . ( http://sheldonbrown.com/harris/derailers-rear.html )

    Questions:
    - If I keep the 105 5700 RD, what is the lowest cassette anyone has experience using (28/30/32?)?
    - If I can get a larger sprocket, do I need extra chain links/new chain?
    - Does anyone have experiences in climbing 28% on a road bike, if so, what ratio were you able to tame the beast with?
    - Does anyone have experience making the Deore or SunXCD RD work with the 10s STI?
    - Are shimano MTB 10s cassettes compatible with road/105 RDs / chains / cranksets?

    Thank you in advance and I look forward to hearing stories of steep hill accomplishments.
     
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  2. jhuskey

    jhuskey Moderator

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    I live in a very mountainous area and have a 12/27 setup. I works fine for me.
     
  3. CAMPYBOB

    CAMPYBOB Well-Known Member

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    25% is a WALL. 28% would rival some of the steepest paved roads on the planet.

    First off, are you certain of those gradients?

    Here are the 5700 spec's:

    Top Features of the Shimano 105 RD-5700 Rear Derailleur Short Cage
    Maximum low sprocket 30T
    Maximum front difference 16T, total capacity 34T

    Medium Cage
    Maximum low sprocket 32T with double chainset
    Maximum front difference 22T, total capacity 40T

    Even a short cage version should easily handle a 28T cassette with a 50T-34T chain ring and shift a 30T with a careful setup of the chain length, B-screw and shift technique. There have been users successfully run a 32T cassette with a short cage, but given the price of a 105 RD, buying a new medium cage makes more sense to me.

    Going with a medium cage to wrap more chain would get you that 32T cassette gear.

    Adding gear teeth does mean adding chain links / length. shimaNO tech documents (available on their website) give instructions on how to determine the length needed for a specific derailleur and tooth count combination.

    I've climbed some steep, steep stuff on criterium gearing, but that was long before Garmin, GPS or bragging that amounted to anything more than, "I climbed Chicken Coop Hill on a 42x21!!!" Training and the brain-dead attitude of a road racer is all it takes. And a witness...in the days before 'Prove It!' on STRAVA.

    Alfeng might be along to provide additional options.
     
  4. PurpleViper

    PurpleViper New Member

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    I just did a 28% .3 mile hill this weeked with a compact crankset and 11-28. Next year I am thinking about using 11-32.
     
  5. jhuskey

    jhuskey Moderator

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    I started out with an 11/21 and struggled on some of the steeps and yes I can verify they range up to 23% gradient. One issue was trying to follow someone that was using an 11/25 setup. My cadence was so slow that I actually fell over into the ditch.That's when I decided to do myself a favor and get a better climbing setup.
     
  6. spdntrxi

    spdntrxi New Member

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    28% is nuts.. Would definitely use the 32 on that
     
  7. alfeng

    alfeng Well-Known Member

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    This may-or-may-not be useful information ... The SunXCD rear derailleur MAY be a good option ...
    • And, while SunXCD appears to be targeting the high-zoot, "touring"/([COLOR=0000FF]Rivendell-type[/COLOR]) segment of cyclists, the price of their rear derailleur does not seem to be unreasonable. On the other hand, it has long been established that Shimano's MTB rear derailleurs could be used in place of their Road rear derailleurs ... Just as when I first did that more than a 12+ years ago it is still considered to be an unauthorized substitution by Shimano ... The XTR 950/952 rear derailleur is probably still my recommendation ... Followed by the XT 750 rear derailleur. Those were my immediate options until I took the time to deduce that the reason that a 9-speed Shimano Rear derailleur (6503) could not theoretically handle a Cog larger than 27t is simply because of the over-sized 11t UPPER Pulley Wheel ...
    BECAUSE, then-as-now, only matching items from the same group should be used ([COLOR=808080]at least, according to the marketing department[/COLOR]). Could the interference be eliminated by simply replacing the 11t Pulley Wheel with a more-normal-for-the-time 10t Pulley Wheel in the upper position?
    • Sure enough, ALL of Shimano's Road rear derailleurs could once again handle Cassettes more suitable for "tourists" and for other riders for whom a tight block was not installed on the bike ...
    Here is a DA rear derailleur with a 10t Upper Pulley Wheel + a 12-34 XTR Cassette ([COLOR=008000]yes, as pictured, the chain is just long enough when on the inner, 39t Chainring + 34t Cog[/COLOR]) ... [IMG ALT="12-34.jpg"]http://www.cyclingforums.com/content/type/61/id/266343/width/350/height/700[/IMG] And, here is a 105 rear derailleur with a 10t Upper Pulley Wheel + 12-34 Cassette on a frame whose rear derailleur hanger has the minimum drop because it was designed to be used with a classic Campagnolo Nuovo Record rear derailleur ... [IMG ALT="11-32.jpg"]http://www.cyclingforums.com/content/type/61/id/266342/width/350/height/700[/IMG] The B-screw was adjusted to cant the parallelogram and thus provide the additional clearance which was needed. If needed, the same B-screw on the rear of the derailleur can be used on "normal" Road rear derailleurs to achieve the 32t-or-more maximum Cog size. If the OP's rear derailleur has a LONG CAGE ([COLOR=008000]GS model[/COLOR]), then there is no real need for another rear derailleur even if an unauthorized 11-32 or 11-34 Cassette is used ...
    • However, if a new rear derailleur is in the offing, then I recommend a Shimano RAPID RISE rear derailleur to ensure efficient downshifting with Shimano's STI Road shifters ...
    Regardless, while not necessary if the rider remembers not to use a Big-Big combination, I think that a longer chain ([COLOR=FF0000]additional segments[/COLOR]) might be a good idea to accommodate the additional teeth.
     
  8. AyeYo

    AyeYo Member

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    - I've used a 12/30 on a 5700 RD without issue. That is the largest cog it will officially support. The 30 was unnecessarily low for all but extreme hills and basically a wasted gear.

    - You might need some more chain. Don't try to add links, get a new chain.

    - I've climbed a half mile hill that was 22-25% and crested at 28% for the final 50ft or so on 34/27. It was not easy, but it was doable. I would not recommend changing your gearing for a single hill. A 12-27 is a great general use cassette and combined with a compact will get even marginal riders up hills just fine. If you can't spin it on this hill, stand up. Gearing the bike to get over a single hill is going to ruin your gear spacing for the other 99.5% of your riding. If you want to try a little bit more gear, get an 11-28 or a 12-30, but don't start getting into 30+ big gears and mountain bike cassettes or you're going to ruin the rest of your riding experiences.
     
  9. spdntrxi

    spdntrxi New Member

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    I've run a 32t cassette for a brief time with my compact 50/34 and 9070 di2 short cage rd on the trainer.. No issues shifting. Chain was sized for 28t.. Ymmv
     
  10. Scott2468

    Scott2468 Member

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    I run 50/34 with a 12/30 on my TCR 0. This got me up everything in the north of Italy, just.
     
  11. MikeWMass

    MikeWMass New Member

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    I have run a compact with 12-27, and have made it up everything I have had to, but some hills were real struggles (sorry, I don't know the grades). I recently picked up a 5703 crank and front derailleur and find that having the lower bailout gear makes life easier on the steepest stuff. I still have the same cassette, so I don't have the big jumps you get with the 32 tooth rears. I have 5600 shifters, so did not have to replace those.
    Back in the day, we only had 5 cogs, so bigger jumps were the norm, as I was never strong enough to ride a straight block in the hills.
     
  12. lectraplayer

    lectraplayer Member

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    27% for me is almost flat ground. I have a few 40% hills around the house. I have to use my middle or small chainrings (whatever they are) and 25-32 tooth rear sprockets. There are times (especially on Link Road, with a couple jumps @ around 50%) I would be glad to have my Shimano OverRange (37 tooth) on this bike. I didn't catch what bike you're on, but I found it much easier to ride a mountain bike on road than a road bike.
     
  13. jhuskey

    jhuskey Moderator

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    40%??? Where do you live Mt Everest? I ski Black Diamond that are only slightly steeper. Sorry but the steepest roads I have heard of are around 35% and the cadence can be so slow on such a climb that some cyclist just fall over. I would advise carrying a parachute.
     
  14. lectraplayer

    lectraplayer Member

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    If i'm not mistaking, 50% is 45 degrees, right? Parts of Mile Hill push that, and a hill on the local magement area (which now is private land) had a hill that is 60 degrees about 70 or 80 feet up. I was a kid with a 5 speed then. Still, all I can say is low gear, and butt in the air.
     
  15. jhuskey

    jhuskey Moderator

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    50% is like 27 degrees to my non-mathematician understanding . Guniness lists the steepest street in the world as 35% .
     
  16. AyeYo

    AyeYo Member

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    100% is 45*.

    I could easily see some off-road areas exceeding 40%. I can't imagine cycling up that though. The 28% I did ride was steep enough that putting down some torque could flip you over backwards if you weren't leaned forward enough.






    [​IMG]
     
  17. jhuskey

    jhuskey Moderator

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    Yep, 23% is about all the fun I want. There are several roads in my area that are 23-24 and I am in a mountainous area. We have a black diamond ski slope that is 45% and it takes a winch-cat to groom it.
     
  18. CAMPYBOB

    CAMPYBOB Well-Known Member

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    Quote by JH:
    "Guniness lists the steepest street in the world as 35% ."

    Sounds about right for a paved road.

    Pittsburg has some that are around 26-27% and those are just plain stupid steep. Rideable? Yes. You better bring your granny and a pair of killer thighs to the party though. Many decent riders fall over after stalling. No shame in that on a hill that steep.

    I have a 20-mile out & back training route that has a bunch of short, steep climbs on it. The return leg has three climbs that have 16% gradients for some portion of them (according to my Garmin). 16% is pretty much a wall. I get over them with a 39 x 25, but if someone puts an honest 26% hill of only 200-300 yards length in front of me I would want a 29 on the back.
     
  19. jhuskey

    jhuskey Moderator

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    I have one 23 that is just under half a mile long .It comes right after a fairly long climb 12% climb. I tend to want to slack off after I reach the top of it since there are several more hill after that and I am on my limit red faced and sucking air through my ears and a**.
     
  20. maydog

    maydog Well-Known Member

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    Here is a nice infographic on steep climbs:

    http://www.citylab.com/commute/2014/02/10-truly-hellish-hills-american-cyclists/8511/

    I hiked part of Waipio Valley road in Hawaii. I did not have time to do the whole thing. There were parts where I felt like leaning forward and going all fours.
     
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