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I'm a 66 year old female rider with a heart condition on a Waterford road bike, currently using Shimano Ultegra 6703 Triple 10 sp chainset-170mm 52-39-30T and find that since I've moved to the Smokies, it isn't enough. I love riding and don't mind changing out ALL of my components if necessary in order to climb without stressing my heart. Would it make sense to swap it all out for mountain bike gearing? Move to SRAM components? Other???I LOVE cycling...but want THE lightest and easiest climbing components available. Please help!!!

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    Do you know current your cassette tooth counts? This is needed to understand what your current low gear is so that we can offer sensible options (e.g., you may just need to change your cassette - and potentially rear derailleur to get more mechanical advantage). After that the other option is to switch to a 1x system as there are lots of options for smaller front chain rings and very wide rear cassettes so that you can do a custom low gearing.
    – Rider_X
    Jun 21 '17 at 19:46
  • @Rider_X I'm pretty sure that a 1x system requires an extra-wide rear hub, so you can't just swap it onto a regular bike. Jun 23 '17 at 4:43
  • I now ride with my Ultegra RD-6700A-GS long cage rear derailler....Ultegra CS 6700 12-30t cassette...with an Ultegra FC-6703 triple 50-39-30 and ST-6703 shifters
    – K.Bacon
    Jun 23 '17 at 21:23
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    Are you 66 years old? 66 inches tall? Jun 24 '17 at 2:25
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    THANK YOU ....this is all very helpful. We are thinking about signing up for several North Carolina, South Carolina and N. Georgia Fondos and t-shirt rides this Fall...I want to be sure I'm prepared for the climbs. At 66 years old I'm pretty much given a pass for a slow time....having said that...I have no problem keeping up with my husband and his friends until I get to the climbs. Let me assure you...the Golden Years are not so Golden!!!
    – K.Bacon
    Jun 24 '17 at 14:04
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Also consider some help from an ebike motor. It may not be fully to your preference, but the small push on the steepest bits will help save your knees and your heart.

This may go against the "purity" ethos that some cyclists value, but at the end of the day its all about riding.

There are retrofit wheel kits for existing bikes, or a bolt-on mid drive, or a much more subtle bottom bracket booster like that woman used in the CX competition (apparently by mistake)

A higher end solution would be to get an electric road bike where the motor is integrated into the frame at the bottom bracket, and batteries are stored in the downtube rather than bolted onto your water bottle mounts or out the back on a parcel rack. But that's much more cost.

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    IMO this is the perfect purpose of e-bike stuff. Enjoy your riding, but don't end your life powering up a mountain sur la plaque. Jun 22 '17 at 9:07
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    Maybe one day...ten years from now...but not yet....I still enjoy every minute of a climb and the accompanying exhilaration of the downhill... Just need more climbing gears!!!
    – K.Bacon
    Jun 23 '17 at 18:42
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There are two main approaches--you can start with one and then add on the other if needed.

  1. Replace your RD-6700-GS derailleur with an XT M771 SGS "9 speed" (also works with 10) rear derailleur. It is important that the new derailleur is NOT labeled "Dyna-Sys" (which won't work). This has a "capacity" of 45 teeth; your front big/small rings are 50/30t (n.b. you also mentioned 52t, not sure which is right). So of the 45 tooth capacity you use 20 in the front, leaving 25 for the rear. That means you can use an 11-36 cassette, which would be a huge improvement (20% gear reduction vs your 30t). Total cost around $120-160 (derailleur, cassette, chain).

  2. Replace your crankset. This is problematic because MTB front derailleurs are not compatible with your road shifter. You'd probably need to use a bar-end shifter instead, which is not expensive but might not be to your liking if you use the front shifter a lot. You could use an XT crankset and get down to say 24t instead of your existing 30t. But you'll lose some top-end gears. Total cost around $150-400 (crankset, derailleur, shifter, chain).

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    After exhaustive research today I followed your suggestion #1, and have ordered a new derailleur, cassette and chain. THANK YOU...I'm confident that will make all of the difference in the world! As soon as my new components arrive and have been tested on a ride or two I'll share the results!. I'm sure I'm not the first old rider who needed a few more "granny gears"...it ya' pardon the pun!!! :)
    – K.Bacon
    Jul 10 '17 at 23:48
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I'd explore the options of smaller chainrings and larger cassettes.

You should be able to find a 10-speed cassette with an 11 or 12 tooth small gear going right up to 32 or 34 or even larger big cog.

On the front you could drop the chainrings from 52/39/30 to 48/36/26 which is more of a MTB triple. I have this on my roadbike, with a 12-28 cassette (the biggest that will fit) and gives me a granny gear ratio below 1, at 24.8 gear inches.


So for the purposes of climbing, lets consider only the lowest gear (the easiest one) which is the smallest front chainring and the largest rear chainring. The rest of the gears are not important.

Your bike has a 30 tooth small front chainring, and maybe a 25 or 28 tooth large. Lets use 28.

  • 30/28 is a ratio of 1.071 so every rotation of the cranks gives 1.07 rotations of the rear wheel.
  • assuming a 700c rear wheel with a diametre of 640mm (622 rim plus a tyre) and you get a rolling circumference of about 2011mm
  • Multiply that by the ratio and every pedal crank rotation gives you 2153mm of forward motion.

By comparison a road triple might have a 26 tooth chainring and a 32 tooth rear largest cog.

  • 26/32 is a ratio of 0.8125 so the rear wheel goes around less often than your cranks.
  • Same wheel diametre results in the same rolling circumference of 2011mm
  • So my bike would roll 1634mm for one pedal stroke

Upshot of that is my bike will "spin" the cranks more on the same grade that your bike mashes the pedals. Also, I have to do 4 pedal rotations where your bike does 3 at the same speed in low low gear.

Limit of Balance

To balance a 2 wheel bike comfortably you need a certain minimum forward speed. If that was 3km/h then your bike has to roll 3000 metres per hour. You're getting 2.15 metres per full pedal revolution, which is 23.3 RPM and that is a horrible mash cadence which will hurt your knees.

My bike would be doing 30.6 RPM which is bad but not as-bad.

Limit of Gradient

This is hard to quantify. As the road pitches up, there is more weight on the rear wheel and less on the front. At some angle, there is NO weight on the frnt wheel and it lifts off the ground, making steering impossible. Depending on your bike that may start becoming evident at 10% and impossible to ride a slope of 25%.

This is why people get off the saddles for the steep bits, to move weight forward and to recruit different muscles.

It also doesn't help that short wheelbase bikes crossed with tall riders are very "lifty"


To explore the ratios and so on, have a play with Sheldon Brown's gear calculator

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  • Oh my....you lost me! I'll have to run that by someone that can put that into Laymans terms! Would that produce granny gears superior to what I now ride with my Ultegra RD-6700A-GS long cage rear derailler....Ultegra CS 6700 12-30t cassette...with an Ultegra FC-6703 triple 50-39-30 and ST-6703 shifters?
    – K.Bacon
    Jun 23 '17 at 18:51
  • @K.Bacon Sorry I do that - edited for clarity.
    – Criggie
    Jun 23 '17 at 23:18
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If money is not a limiting factor, a Shimano Di2 STI shifter with either XT/XTR Di2 mech front and rear or XT/XTR rear and Ultegra/Dura-ace will work.

I've seen this on a few gravel bikes we've had through the shop where the bike had ST-R785 levers and XTR M9050 front and rear derailleurs with a double XTR chainset and 11-40t cassette.

I know the Di2 versions of Shimano Road groups are all lighter than the mechanical versions, so if you want the lightest then Di2 is the answer.

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  • If you are sure, why not add a source?
    – ojs
    Jul 2 '17 at 18:43
  • Do you mean the weights of components? If so, these are from the Shimano 2017 trade sales and support manual... ST-R9100 365g (pair) vs ST-R9150 230g (pair). FD-R9100 69g vs FD-R9150 104g. RD-9100 158g vs RD-R9150 204g. So the Di2 mechs are heavier but overall the Di2 shifters/mechs are lighter by 54g.
    – Bikebum
    Jul 3 '17 at 7:47
  • Thanks, usually "I'm sure" is euphemism for "I just made this up"
    – ojs
    Jul 3 '17 at 9:21
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    Haha! I've edited my answer. I was surprised to hear it was too when the Shimano tech trainer told me. The difference in weight between the shifters is impressive. Begs the question if they purposefully made the mechanical version heavier! 🤐
    – Bikebum
    Jul 3 '17 at 12:52
  • As far as I recall mechanical Shimano shifters were much heavier and more complex than Campagnolo and SRAM. No idea why they made them heavier than competition.
    – ojs
    Jul 3 '17 at 14:01

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