Crankset Upgrade, Advice Please

squa

Hi Cycling Gurus,

I know the title mentions a crankset upgrade, but the main aim here is actually to gather advice around increasing the number of teeth in the front rings and how this will effect overall gear ratios (in lay man's terms) and essentially my performance on the road!

My road bike (Giant Defy) came with an 11 speed 11-34t rear cassette and a 50-34t front crank (Ultegra 6800 front/rear mechs). I know the true roadies here are having a good laugh at such an amateur setup, but I'm a big lump of a lad (100kg) and need as much assistance as possible going up hills!

I've joined my local bike club and am enjoying the challenge of trying to stick with the front group on the Sunday morning social spin. I'm slowly getting better and recently one of the seasoned members suggested that I might benefit from a 53t big front ring. Not quite sure what the overall benefit of this would be, I just told him "thanks" and "I'd look into it"......so here I am!

My cycling style is that I've decent power on the flat and on drags under about 4%, but once the road ramps up to anything over 5% for a sustained period, I quickly start going backwards!

First question is, would I benefit much by having a 53t big ring with my existing rear cassette setup?

(I want to keep this potential upgrade as cheap as possible, so keeping the existing mechs and rear cassette is preferred)

After doing some research earlier, it seems fairly obvious that swapping out the existing big ring for a 53t is a non-runner as the jump from 30t to 53t is too big for the mech to handle. So I'd probably have to go for something like 36-52t or 39-53t instead.

Second question, which front ring combo gives me most assistance on hills with the existing rear cassette?

Last question, is there anything more that I need to consider here or is it as simple as swapping out the front crank/rings and then re-indexing the gears?

A quick search on CRC suggests that this might be a good option;
https://www.chainreactioncycles.com/ie/en/shimano-ultegra-6800-double-11-speed-chainset/rp-prod108725

Thanks in advance for the time anyone puts into reviewing this post.

Squa

Cee-Jay-Cee

If your spinning out (ie your legs can’t pedal fast enough to keep up) in the 50/11 (smallest cog in the back, big on the front) then yes you should change to a 52 or 53 front ring. If not then don’t bother as it’s pointless and yer man that suggested it is talking out his hole.

squa

Cee-Jay-Cee wrote: »

If your spinning out (ie your legs can’t pedal fast enough to keep up) in the 50/11 (smallest cog in the back, big on the front) then yes you should change to a 52 or 53 front ring. If not then don’t bother as it’s pointless and yer man that suggested it is talking out his hole.

I think it's fair to say I'm rarely spinning out. Even when descending there's a fine line between me spinning out and my confidence at such a high speed!

So is the most benefit to having a 52t or 53t big ring only to be seen when in the 11t rear cog or is there also a similar benefit as you move up through the rear cassette?

CramCycle

As CJC said, if your never spinning out, then there is nothing to benefit from. Cadence is far more important than grinding out some massive gear. I presume from your tone your still relatively new? Keepworking with the what you have and focus on building up cadence. Get a cadence sensor before a new crankset and come back to the new crankset idea when your chain and or crankset are worn in a a bit would be my advice. I'm on a 53.39 but certainly didn't need it and in regards club spins I'd be fine with 50.34 most of the time.

Raam

Smaller rings on the front will help you going up hill. Leave your setup as it is.

squa

Thanks for the advice everyone. Always good to seek a second (and third) opinion.

Concensus seems to be to leave the setup as is for now.

dahat

Too big a jump at this stage to the 53 for me.

In time the 52/36 with 11/28 would be ideal but wear our your current components before changing over. As suggested use this time to build your cadence and the changeover will be minimal disruption to you then.

squa

dahat wrote: »

Too big a jump at this stage to the 53 for me.

In time the 52/36 with 11/28 would be ideal but wear our your current components before changing over. As suggested use this time to build your cadence and the changeover will be minimal disruption to you then.

Thanks for the feedback dahat.

Just out of interest, what sort of cadence should I be aiming for?

I've had a cadence sensor for a couple of years so I can check my Garmin Connect for historical progress.

Somebody once told me that when I'm getting tired on inclines, that it can be more beneficial to grind out a bigger gear than spin a higher one. The reason being that my legs will tire quicker spinning a high cadence and I won't get the benefit of building muscle/endurace! There's also the bonus of when you finally get over the top you can pick up speed quicker without noticing a huge difference by having to gear down less. This lead me to think that maybe spinning at higher cadence wasn't such a good idea?

Might just be one man's opinion or maybe its a good training tactic, not really sure!

magicbastarder

i know i'm echoing what people above have said, but jumping from 50t to 53t will help you on downhills, not uphills.

dahat

squa wrote: »

Thanks for the feedback dahat.

Just out of interest, what sort of cadence should I be aiming for?

I've had a cadence sensor for a couple of years so I can check my Garmin Connect for historical progress.

Somebody once told me that when I'm getting tired on inclines, that it can be more beneficial to grind out a bigger gear than spin a higher one. The reason being that my legs will tire quicker spinning a high cadence and I won't get the benefit of building muscle/endurace! There's also the bonus of when you finally get over the top you can pick up speed quicker without noticing a huge difference by having to gear down less. This lead me to think that maybe spinning at higher cadence wasn't such a good idea?

Might just be one man's opinion or maybe its a good training tactic, not really sure!

High cadence uses your cardio vascular system whereas low cadence uses your muscular strength.
I'd aim for 90pm and in the flat when not doing efforts keep it up as well. You'll need your muscle strength at the end of a spin/race not in the middle.

Footnote : I'm a typical low cadence power grinder though I have been trying to increase cadence this winter.. 🀣
Please use the advice given to me!!!!

Cee-Jay-Cee

squa wrote: »

Somebody once told me that when I'm getting tired on inclines, that it can be more beneficial to grind out a bigger gear than spin a higher one. The reason being that my legs will tire quicker spinning a high cadence and I won't get the benefit of building muscle/endurace! There's also the bonus of when you finally get over the top you can pick up speed quicker without noticing a huge difference by having to gear down less. This lead me to think that maybe spinning at higher cadence wasn't such a good idea?

Might just be one man's opinion or maybe its a good training tactic, not really sure!

I don't think that's correct. I can safely say that I have never come across anyone who has shifted up to a bigger gear because they were tired. If your tired on inclines then drop down to a smaller gear and spin your legs. You'll use less energy spinning a lower gear than grinding a big gear.

It appears that the people you are cycling with are as new to cycling as you are and making it up as they go along.

CramCycle

Cee-Jay-Cee wrote: »

I don't think that's correct. I can safely say that I have never come across anyone who has shifted up to a bigger gear because they were tired. If your tired on inclines then drop down to a smaller gear and spin your legs. You'll use less energy spinning a lower gear than grinding a big gear.

It appears that the people you are cycling with are as new to cycling as you are and making it up as they go along.

I used to hear this years ago, from old club cyclists who believed everyone was soft and hills should be ground out at 10rpm tops. As you said, it is all rubbish, you get tired, blow up whatever, the only option that makes sense is to choose a lower gear so you can slow without falling over or you can spin with a bit more ease and keep going.

lennymc

Cee-Jay-Cee wrote: »

If your spinning out (ie your legs can’t pedal fast enough to keep up) in the 50/11 (smallest cog in the back, big on the front) then yes you should change to a 52 or 53 front ring. If not then don’t bother as it’s pointless and yer man that suggested it is talking out his hole.

I'm going to disagree with this. For me, i can notice a subtle difference between a 52 and 53 that to me means that I feel like I go faster with the 53 than a 52. (how subjective!!) Spinning wise, I can comfortably keep 110 - 120 rpm, and peak about 150ish in a sprint.

Im guessing it is down to torque as the radius of the bigger ring is more, so the effecive lever is slightly bigger when you look at the drive train in isolation.
No idea if that's an accurate technical description of whats happening tho. I could be talking through my arse tho.

so, horses for courses. 53 makes me faster (subjectively) even though i can spin happily

I would agree tho, that cadence is important and consistency and cycling more will see the biggest return for the OP. Main thing is to enjoy your cycling Squa, and dont stress the little things

yop

Interesting reading., I struggle on hills badly in races but I'm strong on the flats and decents (94kg).

I'm running a 53 on my main race bike and a 50 on my winter bikes.
And I know train more on hills is the best approach, but I got a groupset (11/30 cassette) there with a 50/34 (172.5 crank) and I have it for sale as I have read I'm better on a 52 on a racing bike, but now I'm wondering reading here if I'm as well to stick the compact I got in the groupset on the bike and possibly suffer less on the hills?

magicbastarder

yop wrote: »

now I'm wondering reading here if I'm as well to stick the compact I got in the groupset on the bike and possibly suffer less on the hills?

surely it's not so much about the gears you have, but the gears you use?
as long as you're not running out of gears, you don't need to re-gear the bike, but change how you use them?

sham58107

Now I a no TDF pro, but I always had a 53/39 12 -23 never any problem, recently bought new bike 52/36 11-28 only real difference is going up hill now spinning a lot more, the 50/34 may be a little low, but probably not, also if you go to 53 is chain going to be okay , someone here will tell you.

eeeee

squa wrote: »

Somebody once told me that when I'm getting tired on inclines, that it can be more beneficial to grind out a bigger gear than spin a higher one. The reason being that my legs will tire quicker spinning a high cadence and I won't get the benefit of building muscle/endurace! There's also the bonus of when you finally get over the top you can pick up speed quicker without noticing a huge difference by having to gear down less. This lead me to think that maybe spinning at higher cadence wasn't such a good idea?
!

This is not true - you can stress your cardiovascular system (spinning) several times (you get your breath back) but your glycogen (sp?!) system once, maybe twice but a proper effort is like a 1 rep max in the gym - it's a once only offer!

Learn how to spin. I can comfortably say you're not spinning out a 50x11. Work on your cadence, you'll go further, easier, and will recover better spinning than grinding. I'm a natural grinder, and trained myself to be a spinner. It can be done. You can keep your power, but being able to spin is a great tool in your arsenal.

I'm a **** climber and race on a 50x34 on the road (11-28 cassette).

secman

My old set up was a 52/42 and an 8 speed block straight 12 to 19, rode w 200 on that.
In latter years i have oped for 50/34 with 11 speed blocks, most of the people I cycle with run 52/39 , i can stay with any of them on the flat, but on long descents say like the Embankment I will struggle to lead them out , but no problem tucking in behind

magicbastarder

nee wrote: »

This is not true - you can stress your cardiovascular system (spinning) several times (you get your breath back) but your glycogen (sp?!) system once, maybe twice but a proper effort is like a 1 rep max in the gym - it's a once only offer!

yeah; consider it like trying to lift 500KG. which will tire you out more; trying to lift 5KG 100 times, or 100KG five times, and allow you to keep going afterwards at the same pace?

07Lapierre

nee wrote: »

This is not true - you can stress your cardiovascular system (spinning) several times (you get your breath back) but your glycogen (sp?!) system once, maybe twice but a proper effort is like a 1 rep max in the gym - it's a once only offer!

Learn how to spin. I can comfortably say you're not spinning out a 50x11. Work on your cadence, you'll go further, easier, and will recover better spinning than grinding. I'm a natural grinder, and trained myself to be a spinner. It can be done. You can keep your power, but being able to spin is a great tool in your arsenal.

I'm a **** climber and race on a 50x34 on the road (11-28 cassette).

Agree...I suspect it's the opposite. In my case I can't pedal fast enough to spin out a 52x11 gear. Any mathematicians here who can calculate what Speed you would have to be dong to spin out a 52x11 gear?

eeeee

07Lapierre wrote: »

Agree...I suspect it's the opposite. In my case I can't pedal fast enough to spin out a 52x11 gear. Any mathematicians here who can calculate what Speed you would have to be dong to spin out a 52x11 gear?

Depends on what cadence you consider spinning out - I'm not a track sprinter, but on rollers I can get up to 170+ (I don't look down after that!). I do some intervals at 130 (not in a huge gear!), so I don't consider that super speedy.
Actual sprinty track people will be comfy at much more.

Gear calculator here:
https://www.velodrome.shop/gear

The maths of the inches /cms per mile/ km is beyond me

ETA if you can spin out a 50x11 you should be on a team of some sort!

dahat

I've never ridden a 53 39 but id imagine I would love the flat speed plus just about survive on fast paced club spins up steep stuff.

I switch between 11/28 & 11/25 cassette on my semi compact and find this a good combination for me at this stage.

magicbastarder

will use the post here as a scratchpad.
50x11 means 4.55 revolutions of the back wheel per pedal stroke.
so a cadence of 80rpm would mean 4800rph (per hour) x 4.55 = 21,840 revolutions of the wheel.
a wheel is about 2.11m around, so 46km/h (21,840 revolutions x 2.11m).
100rpm would be 57.6km/h.

07Lapierre

OP the key to cycling faster is power/weight ratio ( combined with aerodynamics)

A 53/39 chainset will give you higher gears, which will only make you faster if you have the strength to push the pedals at 100rpm or higher.

If you want to spend money on your bike, buy new wheels...deep section,carbon rims make a lovely "woosh" sound and look great too!

07Lapierre

magicbastarder wrote: »

will use the post here as a scratchpad.
50x11 means 4.55 revolutions of the back wheel per pedal stroke.
so a cadence of 80rpm would mean 4800rph (per hour) x 4.55 = 21,840 revolutions of the wheel.
a wheel is about 2.11m around, so 46km/h (21,840 revolutions x 2.11m).
100rpm would be 57.6km/h.

57kph?....sounds a bit low TBH. I've hit 70+kph on descents while pedalling. Mind you, I rarely pedal for long periods...it's usually pedal,pedal,pedal....followed by a long period of freewheeling,which my ass up off the saddle and my chin on my handlebar stem! In my mind I'm the spitting image of Fabian Cancellara on an alpine descent!

eeeee

57kph is way too slow. North of 67+ more like it I think.

lennymc

07Lapierre wrote: »

Agree...I suspect it's the opposite. In my case I can't pedal fast enough to spin out a 52x11 gear. Any mathematicians here who can calculate what Speed you would have to be dong to spin out a 52x11 gear?

about 72kph @120 rpm ish.

http://www.bikecalc.com/speed_at_cadence

lennymc

completely non scientific and possibly veering off topic, but i did a segment recently with a 52/11, a tailwind and a downhill. Iljo Keisse did the same segment during the Giro.
My cadence range was 89 - 120, his was 93 - 113. On part of the segment I was faster than him, but for the rest he was faster than me. He had a lower avg cadence, and a higher avg speed. I'm guessing he was on a 53 or 54

https://www.strava.com/segments/2880993

magicbastarder

07Lapierre wrote: »

57kph?....sounds a bit low TBH.

that's at 100rpm. which is faster than the 70-90rpm which seems to be the main 'biomechanically optimal' figure you see, but far from spinning out.

CramCycle

magicbastarder wrote: »

that's at 100rpm. which is faster than the 70-90rpm which seems to be the main 'biomechanically optimal' figure you see, but far from spinning out.

Biomechanically optimal is different for everyone, and also varies with a range of factors, so can change over the year.

The only hard and fast rule for training, in my opinion, is the faster you can spin, and keep moving, the quicker and faster you will be in race, audaxes, club spins etc.

Wishbone Ash

squa wrote: »

....Somebody once told me that when I'm getting tired on inclines, that it can be more beneficial to grind out a bigger gear than spin a higher one. The reason being that my legs will tire quicker spinning a high cadence....

If you were to run up several flights of stairs taking two steps at a time (big gear) you'll tire a lot quicker than running up one step at a time (smaller gear).