The switch from Compact to 53-39 chainset

dubbs2009

Hi peeps,

I often notice when riding these days that I feel I could be pushing a harder gear on the flat / gently up hills - riding at 23/24mph in top gear on compact chainset (50/34) and smallest cog on cassette (12) doesnt feel like I am working hard enough...

Now an 11tooth rear cog will not make much difference, will it?

So... only option is to change from compact to 53/39 chainset? Should give me some harder gears to turn on the flat - but I will lose the 34 front 25 rear cog gearing for climbing 25% grad hills... What difference would I feel from a 34/25 to 39/25 when climbing? A big difference?

Interested in peeps thoughts...

markhewitt1978

It will make a difference and will be much cheaper than replacing the entire chainset. In any case there's little point in getting a full size double if you don't have a cassette with 11T. You won't lose any lower gears that way either.

chrisaonabike

dubbs2009 wrote:

Now an 11tooth rear cog will not make much difference, will it?

11 teeth instead of 12 means you'll go 12/11 times as fast at the same cadence - that's 9%.

That's not insignificant, and a lot cheaper than changing chainwheels.

Glasgow Iain

I would think you would notice the change from 12 to 11 on the rear. therefore changing the rear cassette would be the cheper option. If you do go down the new chainset route, why not change the cassette at the back as well to a 11-28 that way when running the 39/28 on the hills there is hardly any differnce between that and your old compact set up of 34/25

dubbs2009

Glasgow Iain wrote:

I would think you would notice the change from 12 to 11 on the rear. therefore changing the rear cassette would be the cheper option. If you do go down the new chainset route, why not change the cassette at the back as well to a 11-28 that way when running the 39/28 on the hills there is hardly any differnce between that and your old compact set up of 34/25

OK thanks peeps - sounds like an 11T on the rear would make a good start - I have a 12-27 cassette on a spare wheel I could use if I do go ahead and change the chainset to 53/39

dubbs2009

Is it possible to buy single cogs for cassettes? I am campag - anyone done it? e.g. taken off the current smallest cog on the cassette and replaced with a smaller one?

Grill

An 11t will make a difference. The other option is to go with a super-compact (52/36) as depending on your chainset you can get away with just buying rings as they're both 110bcd.

Dorset_Boy

I have a standard 53/39 with an 11-28 cassette on my good bike, and a compact 50/34 with a 12/25 on my old bike.
I believe the 39/28 ratio is very close to the 34/25 one, so your 'granny gearing' isn't affected.
53/11 is however much quicker than 50/12.

However, as said above, it's much cheaper to change a cassette than the front chainset, so for £50 or less you could try an 11/12 with the existing compact, rather than paying over £150 for a standard at the front.

moonshine

a 50/11 gearing is actually a larger gear than a 53/12
I TT on a std 53/39 chainset and a 12-25 cassette and i am strong enough to ride a 53/39 up most things but i have bought a new P2M PM and went for a compact 50/34 chainset rather than the standard 53.39 as it is more versatile - i can put on a 11T cassette and have a bigger gear than the 53/12 setup, and i don't spin that out -

dubbs2009

moonshine wrote:

a 50/11 gearing is actually a larger gear than a 53/12
I TT on a std 53/39 chainset and a 12-25 cassette and i am strong enough to ride a 53/39 up most things but i have bought a new P2M PM and went for a compact 50/34 chainset rather than the standard 53.39 as it is more versatile - i can put on a 11T cassette and have a bigger gear than the 53/12 setup, and i don't spin that out -

OK thanks - sounds like buying an 11T cog makes the most sense... now I need to find one for a 10 speed Campag cassette setup... anyone???

Grill

dubbs2009 wrote:

moonshine wrote:

a 50/11 gearing is actually a larger gear than a 53/12
I TT on a std 53/39 chainset and a 12-25 cassette and i am strong enough to ride a 53/39 up most things but i have bought a new P2M PM and went for a compact 50/34 chainset rather than the standard 53.39 as it is more versatile - i can put on a 11T cassette and have a bigger gear than the 53/12 setup, and i don't spin that out -

OK thanks - sounds like buying an 11T cog makes the most sense... now I need to find one for a 10 speed Campag cassette setup... anyone???

Errr... no, just buying an 11T cog makes no sense as you'll end up with a nice gap depending on which one you remove. Buying a new cassette with an 11T is what makes the most sense.

dubbs2009

Grill wrote:

dubbs2009 wrote:

moonshine wrote:

a 50/11 gearing is actually a larger gear than a 53/12
I TT on a std 53/39 chainset and a 12-25 cassette and i am strong enough to ride a 53/39 up most things but i have bought a new P2M PM and went for a compact 50/34 chainset rather than the standard 53.39 as it is more versatile - i can put on a 11T cassette and have a bigger gear than the 53/12 setup, and i don't spin that out -

OK thanks - sounds like buying an 11T cog makes the most sense... now I need to find one for a 10 speed Campag cassette setup... anyone???

Errr... no, just buying an 11T cog makes no sense as you'll end up with a nice gap depending on which one you remove. Buying a new cassette with an 11T is what makes the most sense.

OK but I am already running a 25-12 cassette - surely swapping the 12T for a new 11T cog is OK? No need to replace the full cassette? Its only 200miles tops old...

Grill

Dude, the gap you'll have between 11T and 13T is ridiculous.
11T- 119.6
12T- 109.6
13T- 101.2

moonshine

change the entire cassette & sell the 12-25t one once you are satisfied withthe 11-25T one - if not you will have a funny jump from 11-13 at the bottom end -
a 11-25 10sp cassette will have the following rations - 11/12/13/14/15/17/19/21/23/25 and
a 12-25 10 sp cassette will have these ratios - 12/13/14/15/16/17/19/21/23/25

if even possible, just changing the 12T for an i would give you the ratios 11/13/14/15/16/17/19/23/25 and you would notice the jump from 11-13T much more than the jump from 15-17T

I know you are on campag, but with shimano, the 11t uses a different lock ring as well and it isn't possible to change all the ratios independently as the larger sprockets are combined on an carrier.

NewTTer

dubbs2009 wrote:

Hi peeps,

I often notice when riding these days that I feel I could be pushing a harder gear on the flat / gently up hills - riding at 23/24mph in top gear on compact chainset (50/34) and smallest cog on cassette (12) doesnt feel like I am working hard enough...

Now an 11tooth rear cog will not make much difference, will it?

So... only option is to change from compact to 53/39 chainset? Should give me some harder gears to turn on the flat - but I will lose the 34 front 25 rear cog gearing for climbing 25% grad hills... What difference would I feel from a 34/25 to 39/25 when climbing? A big difference?

Interested in peeps thoughts...

Everyone missed the obvious, at the speed the OP is quoting his cadence will be @ 70rpm, way to low, he doesnt need to alter his gearing just maybe look at increasing his cadence

A Cadence of 90 rpm on 50 - 12 setup wil be pushing him along at @ 30mph, that will make him work harder

imposter2.0

^^^ this.

If you are pusing 50/12 at 23-24mph, then you need to learn to spin faster - your knees will thank you for it.

slowbike

NewTTer wrote:

Everyone missed the obvious, at the speed the OP is quoting his cadence will be @ 70rpm, way to low, he doesnt need to alter his gearing just maybe look at increasing his cadence

A Cadence of 90 rpm on 50 - 12 setup wil be pushing him along at @ 30mph, that will make him work harder

About blummin time someone said it!

I'm in a quandry as to replace my 34/50 compact with a 39/53 - as I already have the crankset available. The cassette is 28/11, but I only really use the 34/28 on the steepest stuff and I've done the same hills on my old bike with a 39/26.

I'd like slightly closer ratio changes on the back too - so that means changing the cassette ...

I don't really need to change out of compact as I don't "spin out" until I'm going >40mph (down hill obviously) but as I do spend most of my time on the 50 ring it does seem like the 34 is wasted ... perhaps the 36/5x combo would be better then I could get a 25-11 .... or perhaps not ...
I may be a little indecisive !

dubbs2009

Everyone missed the obvious, at the speed the OP is quoting his cadence will be @ 70rpm, way to low, he doesnt need to alter his gearing just maybe look at increasing his cadence

A Cadence of 90 rpm on 50 - 12 setup wil be pushing him along at @ 30mph, that will make him work harder

Interesting idea! and the cheapest one yet! I have not stuck my cadence monitor on this bike yet - perhaps I will and see what cadences I am riding at... I always prefer lower to higher cadence to grind over the gears rather than spin though...

t4tomo

dubbs2009 wrote:

Everyone missed the obvious, at the speed the OP is quoting his cadence will be @ 70rpm, way to low, he doesnt need to alter his gearing just maybe look at increasing his cadence

A Cadence of 90 rpm on 50 - 12 setup wil be pushing him along at @ 30mph, that will make him work harder

Interesting idea! and the cheapest one yet! I have not stuck my cadence monitor on this bike yet - perhaps I will and see what cadences I am riding at... I always prefer lower to higher cadence to grind over the gears rather than spin though...

Thats fine, but just about every manual ,coach or person who knows what they are taking about will tell you you actually use less energy by spinning a lower gear faster than grinding a high gear more slowly*. So if you want to cycle some reasonable distances, get used to upping the cadence.

*{Something to do with aerobic vs anaerobic.}

Bobbinogs

This site is a good one for seeing the impact of cadence and gearing:

http://www.jozza.net/apps/gear-calculator/

EDIT: note speeds are in km/h

I normally spin at 100-105 and average about 95 but that is what works for me, particularly on long rides. However, my late father in law was a real big gear grinder (probably from the days when blocks were small and had few cogs and the front rings were like dinner plates) but he still managed some fantastic endurance efforts (LEJOG in 3.5 days, for example) so high cadence probably isn't the magic answer for everyone...but may help many of us.

dubbs2009

OnYourRight wrote:

A cadence of 70 RPM can be efficient at low power outputs, but you’ll need to spin a lot faster than that to optimise efficiency at the high power outputs needed to cruise at 24 miles per hour (39 km/h). There is some variation from person to person, but 70 RPM is very low for high power outputs.

But assuming you want to go ahead with grinding:

Your current top gear is 50/12. By comparison:
• 53/12 would be 6 % higher
• 50/11 would be 9 % higher
• 53/11 would be 16 % higher.

53/11 would get your cadence down to 63 RPM at 24 miles per hour! Not a good idea, though.

Fab // thanks for the math!

slowbike

dubbs2009 wrote:

Fab // thanks for the math!

you dropped an S ... here you go - have a few spare .. ssssssssssssssssssss

domgears

t4tomo wrote:

dubbs2009 wrote:

Everyone missed the obvious, at the speed the OP is quoting his cadence will be @ 70rpm, way to low, he doesnt need to alter his gearing just maybe look at increasing his cadence

A Cadence of 90 rpm on 50 - 12 setup wil be pushing him along at @ 30mph, that will make him work harder

Interesting idea! and the cheapest one yet! I have not stuck my cadence monitor on this bike yet - perhaps I will and see what cadences I am riding at... I always prefer lower to higher cadence to grind over the gears rather than spin though...

Thats fine, but just about every manual ,coach or person who knows what they are taking about will tell you you actually use less energy by spinning a lower gear faster than grinding a high gear more slowly*. So if you want to cycle some reasonable distances, get used to upping the cadence.

*{Something to do with aerobic vs anaerobic.}

I understand the principle for this, however for some, myself included, higher cadence just doesn't suit, I have rather heavy legs, comparatively I feel that when I exceed 100 rpm it becomes counter productive and my legs get tired faster than if I push a lower cadence.

My comfort zone is 70-100, remember OP, unless your racing, just do whatever feels most comfortable for you and enjoy yourself, if you want to buy new bit and pieces, go ahead, if they don't work for you change them again and sell off the bits you change, sooner or later you will end up with a set up that's just right for you.

There is no right or wrong, unless your talking about compatibilities, every person is physically different, so what works for 1 person does not mean it will work for others or you

DavidJB

If you switch to a 53/39 you'll be viewed as a cycling deity. Men will want to be you and women will stroke your crankset at every opportunity.

Daz555

DavidJB wrote:

If you switch to a 53/39 you'll be viewed as a cycling deity. Men will want to be you and women will stroke your crankset at every opportunity.

There will be no women around. They will have all dropped him on the first climb.....

NITR8s

24mph in a 50-12 gearing is only a cadence of 75. I would say you can push a lot harder in your current gearing.

Fursty Ferret

Daz555 wrote:

DavidJB wrote:

If you switch to a 53/39 you'll be viewed as a cycling deity. Men will want to be you and women will stroke your crankset at every opportunity.

There will be no women around. They will have all dropped him on the first climb.....

Class. Made me chuckle.

StillGoing

dubbs2009 wrote:

Hi peeps,

I often notice when riding these days that I feel I could be pushing a harder gear on the flat / gently up hills - riding at 23/24mph in top gear on compact chainset (50/34) and smallest cog on cassette (12) doesnt feel like I am working hard enough...

Now an 11tooth rear cog will not make much difference, will it?

So... only option is to change from compact to 53/39 chainset? Should give me some harder gears to turn on the flat - but I will lose the 34 front 25 rear cog gearing for climbing 25% grad hills... What difference would I feel from a 34/25 to 39/25 when climbing? A big difference?

Interested in peeps thoughts...

Without reading through every post; if you're only doing 23/24mph when in the 50 ring and using the 12 tooth cassette, then your cadence must be very low? Have you considered spinning harder.

And having now read the other posts, I see others have come to the same conclusion. :oops:

morstar

philthy3 wrote:

dubbs2009 wrote:

Hi peeps,

I often notice when riding these days that I feel I could be pushing a harder gear on the flat / gently up hills - riding at 23/24mph in top gear on compact chainset (50/34) and smallest cog on cassette (12) doesnt feel like I am working hard enough...

Now an 11tooth rear cog will not make much difference, will it?

So... only option is to change from compact to 53/39 chainset? Should give me some harder gears to turn on the flat - but I will lose the 34 front 25 rear cog gearing for climbing 25% grad hills... What difference would I feel from a 34/25 to 39/25 when climbing? A big difference?

Interested in peeps thoughts...

Without reading through every post; if you're only doing 23/24mph when in the 50 ring and using the 12 tooth cassette, then your cadence must be very low? Have you considered spinning harder.

And having now read the other posts, I see others have come to the same conclusion. :oops:

Same here. My 10 mile pub is 23:16 (just under 26mph) ridden on a compact and I've yet to use my 12 tooth cog on the flat during a TT. Guess we're all different but genuinely surprised this isn't enough gears at 23 mph.

Celt100

I suggest getting a set of rollers this winter to train on I did this last winter to get fitter primarily but when I got into it utilising different training techniques it made a huge difference to my speed and power when I finally got back on the road in the spring.

I was the same heavy build with big legs struggling to keep a good Cadence up but rollers have so much advantages and really help with balance, cadence, pedal technique etc etc, plus I went from 90kg to 82kg all this from 3 x 1hr sessions a week.

Good luck Shaun.

tiglon84

I'm considering doing the same as the OP, but for different reasons. I have plenty high enough gears for cruising along on the flats, but I find on some descents my legs are spinning as fast as they can on 50-12, but I max out at about 45mph (although this is recorded on Strava iPhone app so not sure how accurate it is!).

I don't use the 34-25 on any hills any more, my default gear for 10%+ is 34-19 (I think, somewhere in the middle anyway). So I'd be quite happy to trade the lowest gears that I never use for a bit extra at the top end that I might use on rare occasions.

I am however very much a newbie, and am far from understanding everything about gear ratios and cadence, so it might be a big mistake. Best thing I can think of doing is having a test ride on a full size double, and that might be a good reccommendation for OP too.