Not sure if I should get a new chainset

Geordi

My current bike has a 48/32 chainset with an 11-32 cassette. I really like it for climbing but during group rides I always seem to get dropped on long descents (maybe I'm just not good at descending) and small rolling hill descents. The guys I ride with say I should get a 50/34 because I'll never be able to keep up, but I'm not sure. They also say I'm wasting energy trying to keep up on flat terrain with a 48/32. They seem to think that I will save energy using a bigger ring in the front and an easier gear in the back rather than a smaller ring in the front and a harder gear in the back. Is that truly the case ?

timothyw

What they're saying is accurate in a strictly scientific sense, bigger gears turning bigger cogs is marginally more efficient - but it isn't what is making you struggle.

You need to practice descending, and riding hard on the flat.

I'm guessing you might not be the largest person from where you are describing your struggles?

Trust me, you are better being small and having the advantage going uphill.

I'd suggest finding someone selling a standard (53/39) chain set if you want to test the accuracy of their theory.

Mad_Malx

^but you will lose the equivalent of your lowest 2 gears. Are you ok with that?

styxd

They are talking bollocks.

sloppyschleckonds

Can someone post what cadence he would be spinning out at in a 48-11 at say 30 mph

mrb123

SloppySchleckonds wrote:

Can someone post what cadence he would be spinning out at in a 48-11 at say 30 mph

87.

Cadence of 102 gets you 35mph in 48-11.

First.Aspect

A 48x11 is a significantly longer gear than a 50x12. It is slightly longer than a 52x12 and slightly shorter than a 53x12.

How many of your riding buddies have calculators on their phones?

N0bodyOfTheGoat

Could be descending skills, I know it's one of my weaknesses, but are you the lightest of your group by a significant margin including the bikes?

You could always bolt on the climbs, they catch up on descents and then you draft for your life on the flats.;)

photonic69

What is your average group riding speed? What is the average climbing per ride? How far is your average ride?
I've just got a new winter bike with the same chainset and I'm actually faster on all of the climbs and faster on the flats as my legs are not so tired after a long climb.

Geordi

NitrousOxide wrote:

Could be descending skills, I know it's one of my weaknesses, but are you the lightest of your group by a significant margin including the bikes?

You could always bolt on the climbs, they catch up on descents and then you draft for your life on the flats.;)

I am by far the lightest rider of the group at 59 kg

Geordi

PhotoNic69 wrote:

What is your average group riding speed? What is the average climbing per ride? How far is your average ride?
I've just got a new winter bike with the same chainset and I'm actually faster on all of the climbs and faster on the flats as my legs are not so tired after a long climb.

The averages are about 1250m of climbing with a distance of 100km and an average speed of 27km

joe_totale-2

That's the trouble with group riding. Everyone always waits at the top of climbs to regroup but never at the bottom of them.

Thus the climbers aren't able to make the most of their advantage!

super_davo

Your bottom gear is 1:1 which is exceptionally low... Do you use it much? Do you do 95% of your riding in the big ring?
If you're not using the largest ring on your cassette or the inner chainring much then they have a point. Changing to a 50/34 or 52/36 will increase your gearing throughout the range, changing to 11-28 will tighten up your gearing and reduce cadence jumps.
I like to spin and find 34/28 enough for me to get up some pretty severe gradients.
I know it's good to spin and all that, but carrying around a dinner plate cassette and not using it much is just dead weight.

photonic69

Geordi wrote:

The averages are about 1250m of climbing with a distance of 100km and an average speed of 27km

Our average run is similar maybe we do a little more climbing and a little less distance but our av speeds are much the same (you maybe a little more). I had no issues with my 48-32 chainset with 11-32 cassette. I was often at the top first overtaking most and had no trouble pushing out 30mph (46kph) on a flat (with tailwaind). Not sure what the cadence was as this bike is a "commuter" so only my Garmin on top. Didn't feel like I was spinning out though I do like a high cadence.

How long have you been riding this particular bike? Maybe just getting used to it?

Geordi

super_davo wrote:

Your bottom gear is 1:1 which is exceptionally low... Do you use it much? Do you do 95% of your riding in the big ring?
If you're not using the largest ring on your cassette or the inner chainring much then they have a point. Changing to a 50/34 or 52/36 will increase your gearing throughout the range, changing to 11-28 will tighten up your gearing and reduce cadence jumps.
I like to spin and find 34/28 enough for me to get up some pretty severe gradients.
I know it's good to spin and all that, but carrying around a dinner plate cassette and not using it much is just dead weight.

You definitely have a point. I honestly never use the 32/32 unless the grade is extreme and there's only one road in my area where it would be very useful. On the other hand, I like to bikepack and the extra gears really come in handy with all the extra weight, but in that case, I could just swap out the cassette when I want to bikepack. I'll probably buy an 11-28 cassette for normal road biking/group rides. The bike I used to ride was an 8 speed with 48/32 in the front and 13-26 and for the most part, that was just fine for me. Don't know why I didn't think of this before. Thanks you !

Geordi

PhotoNic69 wrote:

How long have you been riding this particular bike? Maybe just getting used to it?

I've been riding this bike a over a month now. It's a specialized diverge comp e5. I had the lower end model before. It's definitely more of an adventure style bike, so there are some cons to using it as a pure road bike. I probably should've mentioned this in my first post lol.

shirley_basso

Could be a case of some lower rolling resistance tyres

Geordi

Shirley Basso wrote:

Could be a case of some lower rolling resistance tyres

Was thinking the same thing. For the most part everyone else is on 25mm

shirley_basso

Geordi wrote:

Shirley Basso wrote:

Could be a case of some lower rolling resistance tyres

Was thinking the same thing. For the most part everyone else is on 25mm

If you're on knobbly tyres it could make your life easier. 28 vs 25 for slicks won't make much difference.

w00dster

Are you on the stock tyres still? Knobbly 38mm tyres? If so then a change to 25mm tyres would make a difference.
For my bike packing duties I run a completely different set of wheels / tyres and cassette. I just bought a cheap pair of wheels for mixed (road/off road duties).
A lot less faffing about than having to swap tyres and cassette for each ride type.
Lastly, the other thing you can do is make sure you are as aero as possible. If you're a nervous descender you may be sat more upright, while the heavier riders may be as low as possible using aero and extra weight for speed.
I wouldn't change the chainring myself if you are doing bike packing. I'd just look at running an 11-28 cassette and the 25mm good rolling resistance tyres.