66 yo female road bike rider needs advice on THE BEST CLIMBING components/groupsets available!

Question

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!!!

Answer 1

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.

Answer 2

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).

Answer 3

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.

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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"

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

Answer 4

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.