Chainset advice please

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cd365

Guru
Location
Coventry, uk
This year I have tried to change my riding style from grinding a big gear to one of a high cadence. I have a compact Shimano 105 50/34 chainset and just tried to use the 34 ring spinning a high cadence. This has worked in that my legs don’t feel as tired all the time on my commute.

On my rear cassette I run an 11/23.

Recently I have been thinking of changing my chainset to a 53/39. I think the 39 might be a bit better for me since I easily pedal out (I try not to change into my big ring because I know I will just stay in it; it’s a mental thing). I’m assuming that I would need to raise my front derailleur and buy a longer chain, how long should the chain be? I don’t think I would have to change the bottom bracket?

Another option would be to run a 50/39 just changing the 34 ring to a 39 ring. Stupid idea? I do like the option of being able to run a 50/34 or 53/39 at will (well just by changing the chainset and chain).

Any advice/opinions welcome. Thanks
 

cyberknight

As long as I breathe, I attack.
I changed my inner to a 36 , seems to work nicely .
Im not sure you can change the inner to a 39 anyway but it depends on the BCD of your chainset, most compacts 110 bcd can run a 52/36 max and then you have the 130 bcd for 53/39 .
These new fangled one size bcd that has just come out im not sure on .
 
OP
OP
cd365

cd365

Guru
Location
Coventry, uk
My BCD is 110mm; a Shimano 105 FC5700 50/34t
I might look at a 36 if I can find one suitable.
I think it might just be easier to buy a 53/39t Chainset!
 

Citius

Guest
My BCD is 110mm; a Shimano 105 FC5700 50/34t
I might look at a 36 if I can find one suitable.
I think it might just be easier to buy a 53/39t Chainset!

Most ring sizes are available in 110bcd. The logic of what you are trying to achieve is an entirely different thread though....
 
If you get the chance have a look at the ceramic bearing based BB's - I use a GUB Hollowtech II type BB - as they offer a slightly smoother operation which is ideal for high cadence pedalling.
 

gbb

Legendary Member
Location
Peterborough
I dont know what the terrain is like in Coventry but here in Peterborough we have a choice of flat Fens or gently rolling hills of Northants. My last two bikes came with compacts and 11-25 IIRC, wholly innapropriate for round here so I always ran a 50/40. It worked brilliantly for me, only need to change the dog fang position if ones fitted.

£15 at the time for a 40t, 15 minutes to fit and you're away. Its just finding the right one between 34 and 40(which is the maximum inner I think)..to suit your terrain.
 

Citius

Guest
I used to run a 42 inner, so I doubt if 40 is the maximum. Also, ignore anyone who tells you there is a quantifiable benefit to running ceramic bearings.
 

Citius

Guest
I would be interested in your thoughts.

I cycle around rolling Warwickshire countryside.

Well, the cadence thing bothers me a bit. It should really be self-selected, rather than forced. If you are forcing yourself to spin easy gears at unnecessarily high cadences, then you are unlikely to be riding to your full potential - and there's no particular benefit to artificially high cadences anyway.
 

mythste

Veteran
Location
Manchester
Well, the cadence thing bothers me a bit. It should really be self-selected, rather than forced. If you are forcing yourself to spin easy gears at unnecessarily high cadences, then you are unlikely to be riding to your full potential - and there's no particular benefit to artificially high cadences anyway.

Interesting advice, but it appears to me that OP has spent a long time grinding out too big of a gear, so "artificially" high cadences to him may well be more in line with a "normal" cadence day to day.

At least that's how I interpreted it!
 
OP
OP
cd365

cd365

Guru
Location
Coventry, uk
Well, the cadence thing bothers me a bit. It should really be self-selected, rather than forced. If you are forcing yourself to spin easy gears at unnecessarily high cadences, then you are unlikely to be riding to your full potential - and there's no particular benefit to artificially high cadences anyway.
I tended to sit in a high gear and spin a cadence of low 70s. This often left me with tired thighs. I decided at the start of this year to try and change my cycling style, i.e. a cadence of around 90. To do this meant that I was better off sitting in my smaller ring, the benefit of this has been that my tired are a lot fresher and I can now easily cycle 20+ miles 7 days a week (20 mile a day commute and a couple of longer rides at the weekend).
I do think that I would benefit from increasing the size of my small ring from 34t to something bigger so I get the full benefit out of my rear cogs, I rarely use the first 4.
The only downside to a higher cadence is that I am slightly slower but if/when I want to I ride in my 50t ring and put a faster ride in, I did it a fair bit at first but am doing it less and less, the only downside is that I have no real Strava improvements this year!
 

ColinJ

Puzzle game procrastinator!
I dont know what the terrain is like in Coventry ...
Ideally suited to a 53/39!

I made do with a 53/39 on my best bike up here in mega-hilly Yorks/Lancs for a long time before finally conceding defeat and sticking a triple chainset on the bike, but I had no problems with it in Coventry and the surrounding area.
 
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