Gear Ratios

[johnpf]

I am 76 years old and have been riding, mainly on the road, for about 30 years

My summer riding is now 300 to 400km at average speed about 18kph

I live in the south peninsula. My routes include Millers Point, Smits, Cape Point Reserve, Red Hill, Slangkop, Ou Kaapse Weg, Chappies, Suikerbossie, Camps Bay, Constantia Nek and Boyes Drive

Over 12 months, my elevation gain is about 33500metres

Since January,2017, I have been riding a Cannondale CAAD12, with a drive train of 50/34 and 11/32

I am getting noticeably slower going uphill and am hoping for suggestions about different gearing, which would allow me to spin rather than grind up gradients 

I would still like to descend fast and go maintain speed on flatter terrain

[David Marshall]

To give any meaningful advice you will need to give more information.  

Specifically what groupset do you have? (Speed and model numbers on the FD, RD and shifters as well as the length of the RD cage)

Also the crank information - number of bolt holes on the ring and the PCD.

[DirtyDan]

I know nothing about road chainring combinations, but is it not as simple as changing your 34 to a 32 in the front and keeping the rest the same?

[John Gomes]

E-bike

[Baron]

Maybe this, still available new.

Shimano Tiagra FC-4703 Tiagra triple chainset 10-speed; 50/39/30; triple; 172.5 mm.

[Bub Marley]

The easy answer is a bigger cassette. However, a bigger cassette means you might need to change your rear derailleur a wall to handle that. I would go for an 11-36 cassette and then upgrade to a medium cage derailleur. 
 

The suggestion above about getting an e-bike is sound Advice as well. If you can afford it, it’s definitely something to look into. 

[betaboy]

Cannondale… I like this guy already!👍🏻✅

[johnpf]

18 hours ago, David Marshall said:

To give any meaningful advice you will need to give more information.  

Specifically what groupset do you have? (Speed and model numbers on the FD, RD and shifters as well as the length of the RD cage)

Also the crank information - number of bolt holes on the ring and the PCD.

I am away from home at the moment, but I advise the following.

I weigh 72kg and am 1.85m

Except for the rear cassette all equipment is pre 2017, when, after breaking a Cannondale Super Six frame, I transferred everything onto a CAAD12 frame

Levers 105

Drive train Dura Ace 10 Speed 50/34

Derailleurs Dura Ace

Cassette SRAM 11/32 changed from a 28 about 5 years ago

[The Ouzo]

18 hours ago, DirtyDan said:

I know nothing about road chainring combinations, but is it not as simple as changing your 34 to a 32 in the front and keeping the rest the same?

this would be my suggestion as well. Although I also dont know if its technically possible.

[DieselnDust]

a 32 on a 110 BCD is not possible.

[NotSoBigBen]

24 minutes ago, DieselnDust said:

a 32 on a 110 BCD is not possible.

I imagine one is then going onto 'sub compact 48/32 cranks? But then again the OP still wants to go 'fast' 🤔

[DieselnDust]

38 minutes ago, NotSoBigBen said:

I imagine one is then going onto 'sub compact 48/32 cranks? But then again the OP still wants to go 'fast' 🤔

correct and then we're into the 96mm or 74 mm inner chainring BCD

[ChrisF]

3 hours ago, DieselnDust said:

a 32 on a 110 BCD is not possible.

 

You had me running to the spares box on this one .... 

 

32 on a 110 BCD is one tight fit !!!  But it is available for a MTB.  

 

Absolutely no idea if this is an option for a road bike.

 

[Prince Albert Cycles]

On 9/29/2025 at 7:22 PM, Baron said:

Maybe this, still available new.

Shimano Tiagra FC-4703 Tiagra triple chainset 10-speed; 50/39/30; triple; 172.5 mm.

I think this is the solution. Would need a 3 speed left shifter as well

[DieselnDust]

3 hours ago, ChrisF said:

 

You had me running to the spares box on this one .... 

 

32 on a 110 BCD is one tight fit !!!  But it is available for a MTB.  

 

Absolutely no idea if this is an option for a road bike.

 

Mtb uses a 104 BCD.

i think there was a5 bolt 110bcd 32t chainring available a few years back but I can’t remember if it was wolftooth or absolute crap that manufactured it. It was very unsuccessful. The 2x sub compact cranks use a 110bcd for the big outer chainring and either a 96mm or 74mm bcd for the inner chain ring that can then be sized down to a 26t.

sram may have a 32 but on a 107mm BCD. That’s just enough clearance for the chain ring bolt to not snag the chain but inconvenient enough to not be adopted by other manufacturers. You see good ideas are not adopted by the bike industry. They would rather have a million different standards for the same thing so you can mortgage the house for a chainring .

 

i found these on ebay. you can see there isn't a heck of a lot of material around the mounting bolt for a 30T and 32T on 110mm BCD

https://www.ebay.com/itm/123706511747

they 5 bolt and 4 bolt mount.

I'm not prepared to be the guinea pig

Edited September 30, 2025 by DieselnDust

[Baron]

24 minutes ago, Prince Albert Cycles said:

I think this is the solution. Would need a 3 speed left shifter as well

 

Op can check, I do not know if Dura Ace  is same, but most Shimano 105 and Ultegra 10-speed left shifter is designed to work with both double and triple chainrings by adjusting the lower and upper limit screws on the front derailleur. These "dual-use" or "dual-purpose" shifters allow for flexibility in the number of chainrings, so you can use the same shifter for a double or triple crankset without needing a separate, dedicated shifter.  

 

 

 

Edited September 30, 2025 by Baron