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  1. #1
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    Weight vs Friction vs Gear Ratio

    I want to buy a bike that I can use on the steep urban hills where I live. When I leave my house it's easy, I go straight down. Getting back could be a problem.

    MTB's have great gear ratios but they have friction and weight working against them.

    I really like the idea of a road bike, but even those with a triple with Shimano 105's don't have front to back gear ratios that fall below 1.1 or so. Should a fit rider be able to make it up a steep urban (i.e. paved) hill, one that is challenging to walk up, with a 30/39/50 on the front and a 12-27 cassette on the rear? Or should I go with a hybrid?

    I really need help before I invest $1400 or so in a bike.

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    A road bike will do just fine as long as you get a cassette with a good granny gear. Have the bike shop change the cassette from a 12-27 to something with a 30 or 32-tooth big cog. It will help.

    I had a 12-25 and ended up with a 12-28 which helped me on the hills around here.

  3. #3
    Senior Member bobbycorno's Avatar
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    ...and if that's not low enough, any bike shop worthy of the name should be able to swap out the road rear derailleur for an MTB unit, replace the 25t cassette with an 11-34 and throw on a 24t ring in front. If they tell you it can't be done, it's time to go somewhere where they know what they're talking about.

    SP

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    I'm considering a Cannodale CAAD9 5, and two LBS say that swapping out the rear cassette (12-27) or the front crank 30/39/50 is difficult because of the Shimano 105 set?

    Should I punt and go for a less expensive bike with Tiagra's that can be swapped?
    I need to get up my hill.

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    Prefers Cicero cooker's Avatar
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    What hill? Can you determine the percent incline?

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    I live in Salt Lake City. Lets say a very long hill at 8-10%

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    Ouch

  8. #8
    Senior Member BengeBoy's Avatar
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    Two options to do this in a road bike:

    1. Find a cyclocross bike or a touring bike that comes stock with really low gearing. Like a Surly LHT complete, Novara Randonee, etc.

    2. Get a good bike shop to set you up w/a triple and big rear cassette. My "good" road bike has a triple road crankset up front with a 28-tooth inner ring. In the back, I have a huge cassette with a 9-tooth 34-inch cog. I use brifter to shift, and use a device called a shiftmate to connect the brifters (which are 10-speed compatible) with the rear cassette. It is a little tricky but a smart bike shop should be able to figure this out. (To be more specific, I have Dura Ace triple crank up front, DA brifters, XTR long cage rear derailleur, Shimano 9-speed cassette in rear. It works).

    You don't have to get a hybrid or MTB just to get low gears. Nor should you have to compromise on the quality of bike you want.

  9. #9
    Senior Member BCRider's Avatar
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    Even after 17 or so years of riding I think I'd be walking up that hill with my bike at my side a lot on that one.

    If it's only a couple or three blocks long then I'd likely suck it up and ride. Any longer and varying upper portions would be walked depending on my energy levels that day.

    So... how long is it?




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  10. #10
    Senior Member Bill Kapaun's Avatar
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    : I really like the idea of a road bike, but even those with a triple with Shimano 105's don't have front to back gear ratios that fall below 1.1 or so. Should a fit rider be able to make it up a steep urban (i.e. paved) hill, one that is challenging to walk up, with a 30/39/50 on the front and a 12-27 cassette on the rear? Or should I go with a hybrid?"

    You may have to go to a mountain cassette, such as an x-32 or x-34.
    That will mean you also have to install a "mountain" RDER to handle the larger cog.
    "Road" RDER's are rated to a 27-28T largest cog, although they;ll usually handle a 30T.
    Another factor regarding "low end power" is crank length. A longer crank gives you a bit more leverage.

  11. #11
    just keep riding BluesDawg's Avatar
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    A 110 BCD crank with 26/36/48 rings will solve your problem. If you can't find a bike that comes with one, swap it out. 110 BCD should be the standard crank for non-racing bikes. Much more versatile.

    The rear derailleur swap won't work for 10 speed setups as there are no standard 10 speed MTB cassettes.
    The more you ride your bike, the less your ass will hurt.

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    Senior Member BlazingPedals's Avatar
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    Quote Originally Posted by jonathan20 View Post
    I live in Salt Lake City. Lets say a very long hill at 8-10%
    A road bike shouldn't need any special gears to make it up a 10% grade. I've done MILES of 8-12% at a time on my recumbent, and everyone knows recumbents can't do hills at all.

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    A mtn bike will weigh a bit more, but with slicks, I don't buy the friction argument. Don't dismiss totally the possibility of a mtn bike if you have a lot of hills. Bersides, you could have both - mtn and road.

  14. #14
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    10% isn't too bad. I'm moderately fit and can do a couple of miles of 15% plus on 34 x 27. Might take some hardening up. Speed work, intervals, power sprints will get the mindset and power output skills up.

    Regardless, hills are no different from a fast flat ride except slower with appropriate gearing, as described above.

  15. #15
    Senior Member staehpj1's Avatar
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    Quote Originally Posted by jonathan20 View Post
    I want to buy a bike that I can use on the steep urban hills where I live. When I leave my house it's easy, I go straight down. Getting back could be a problem.

    MTB's have great gear ratios but they have friction and weight working against them.

    I really like the idea of a road bike, but even those with a triple with Shimano 105's don't have front to back gear ratios that fall below 1.1 or so. Should a fit rider be able to make it up a steep urban (i.e. paved) hill, one that is challenging to walk up, with a 30/39/50 on the front and a 12-27 cassette on the rear? Or should I go with a hybrid?

    I really need help before I invest $1400 or so in a bike.
    I would consider that gearing more than adequate for a road bike (but definitely NOT for loaded touring). I find a 39/28 adequate for the much steeper but shorter hills here in the east. It does depend on your conditioning and preferences though.

    Also as someone said it isn't a huge deal to change the gearing if you need lower.

  16. #16
    Pat
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    Well, you might be able to sit and spin on a 10% grade with a 30-27. For long steep grades, I like a one to one. I have heard that one can get away with a 28 small tooth chain ring on a shimano road triple, but I have never tried it.

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    Senior Member SaiKaiTai's Avatar
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    Quote Originally Posted by Pat View Post
    Well, you might be able to sit and spin on a 10% grade with a 30-27. For long steep grades, I like a one to one. I have heard that one can get away with a 28 small tooth chain ring on a shimano road triple, but I have never tried it.
    I used to have a 30/30 setup on my LeMond with a 105 gruppo
    Worked fine. Sure, I had to do some adjusting of the RD to put a little more slack in the chain and make up for the extra 3 or 4 teeth I added (the rear cluster used to be a 26 or 27) but no problems.
    '13 Felt Z3 - '08 Jamis Aurora Elite - ('07 Giant OCR C2)

  18. #18
    Senior Member BengeBoy's Avatar
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    Quote Originally Posted by Pat View Post
    I have heard that one can get away with a 28 small tooth chain ring on a shimano road triple, but I have never tried it.
    My road bike set-up:
    28 inner chainring Dura Ace triple
    Largest rear cog: 34 teeth
    Dura Ace brifters
    JA Shiftmate

    With a 175mm crank, that's a low gear of about 22 gear inches.

    Even given the pathetic engine my bike is stuck with, we don't walk up hills.

    to the OP: if your bike shop can't figure this out, buy your bike elsewhere. They also should be happy to swap cranksets, cassettes, derailleurs for a *very* modest charge if they are selling you the bike at full retail.
    Last edited by BengeBoy; 08-14-08 at 03:42 PM.

  19. #19
    Senior Member gcottay's Avatar
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    You do not seem to be riding now, so a test is in order. Test ride a bike like you think you want on your hill. That will give you invaluable information.

    Many fine bikes are sitting covered with dust because a new rider could not handle a hill because the gearing was set up for strong riders.
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  20. #20
    Time for a change. stapfam's Avatar
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    SKT has not been riding that long and he lives in a hilly area. He quickly learnt that the only way to ride hills- Is to ride them. He may have taken a couple of breaks up the long ones and he may not have been going up them fast- but All that has changed. He still takes a rest up some hills- but they are longer- steeper and harder than the ones he started on.

    And from another rider that lives in a hilly area- Get a triple on the front- and possibly go 9 speed to enable lower gears to be fitted on the Cassette if you find you need them. 10 Speed does have a problem in going lower than a 27t on the back- but I can assure you- 30/27 is a pretty low gear for a road bike up hills.

    Now longer mountains are a different matter.
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  21. #21
    gone ride'n cyclinfool's Avatar
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    First of all I am green with envy on your location - one place I would like to live but the wife want's nothing to do with the LDS - so that nix's my retirement plans.

    All I know of SLC roads are the drive up little and big cotton wood - these roads are not steep but they are a long climb. A road bike with a typical cassett of 12/15 or 12/26 and a triple should do just fine. If you find it too much of a challenge at first, take it slow and take breaks - eventually you will be able to climb the whole thing. The longest climb I have here is 3000' over 8 miles - you may have some longer ones there.
    "Of all the things I ever lost I miss my mind the most." Mark Twain
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  22. #22
    Senior Member Road Fan's Avatar
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    I have two bikes set up with pretty low gears: my Woodrup has 52/42/30 and a 13-26, and my Mondonico has a 53/39 and 13/29 (campy 10). Not long ago my Trek as well had a 52/40 with 13/34. For my hills here (Ann Arbor) I used the bottom on each of them. But now my Trek has 53/39 and 13/23, and I can climb fine around here and it's a heavier bike thatn the others!

    My legs are getting stronger. Sooner or later your need for deep low gears may abate, as well!

  23. #23
    Senior Member deraltekluge's Avatar
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    Quote Originally Posted by BengeBoy View Post
    With a 175mm crank, that's a low gear of about 22 gear inches.
    Crank length has nothing to do with gear-inches. A longer crank requires less force exerted at the pedal, but one revolution is still one revolution, and gear-inches are defined as the diameter of a directly driven tire that would produce the same distance traveled for one revolution of the crank.

    A mountain bike with 22/32/44 chain rings, 11-34 cassette, and 26 x 2.125 tires would have a range of 16.8 to 103.8 gear-inches http://www.sheldonbrown.com/gears/
    Last edited by deraltekluge; 08-14-08 at 08:43 PM.

  24. #24
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    Quote Originally Posted by jonathan20 View Post
    ...30/39/50 on the front and a 12-27 cassette on the rear...
    I do such hills with 50/36 on the front and 11-27 on the back. Seems to me that what you suggest above should certainly work.

  25. #25
    Senior Member deraltekluge's Avatar
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    Quote Originally Posted by The Smokester View Post
    I do such hills with 50/36 on the front and 11-27 on the back. Seems to me that what you suggest above should certainly work.
    With 700 x 23 tires, that'd give you a range of 35.0 to 119.5 gear-inches. The lowest gear would be more than 2:1 higher than the mountain bike's.

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