Chainring 34T vs 36T oval

[100Tours]

1 hour ago, Christie said:

AFAIK oval rings have been proven to be ineffective - they came back into fassion when power meters became more common. Older power meters had a lower data sample rate, and some of these measured more power for oval rings. Modern meters allow higher sample rates, resulting in zero nett benefit from an oval ring.

Assuming the power meter measures input power (?) then changing rings won't make a difference - they're still the same legs.

What ovals are meant to do is to reduce the effective gear size in the dead spot. This means that the smaller muscles that you're using to get the crank through the dead spot have an easier job to do, and therefore less fatigue. 

[jcza]

32 Chainring with 52 cassette? Are you riding in the Alps? Get a 34 ring. 

[DieselnDust]

3 hours ago, openmind said:

SRAM is either 10/50 or 10/52

Shimano is 10/51

I prefer the Shimano ratios, they don’t have the “bail out” gear philosophy, the ratios are spaced out more evenly so you can use the whole block. 

Actually that’s subjective.

the lower the ratio goes the bigger the jump needs to be too maintain power out output at rpm. 10-52 is ideal. It will of course vary from rider to rider.

[DieselnDust]

2 hours ago, 100Tours said:

Assuming the power meter measures input power (?) then changing rings won't make a difference - they're still the same legs.

What ovals are meant to do is to reduce the effective gear size in the dead spot. This means that the smaller muscles that you're using to get the crank through the dead spot have an easier job to do, and therefore less fatigue. 

The oval still pulls the same amount of chain through the dead spot as a round chainring. Oval is just marketing smoke and mirrors also known and blatant lies dressed up as science

[swingTOpeddle]

2 hours ago, jcza said:

32 Chainring with 52 cassette? Are you riding in the Alps? Get a 34 ring. 

Shouldn’t it be based on a rider’s ability? Or would you suggest this for a 200 FTP person who’s 120kg also?

[guidodg]

biggest difference for me on an MTB with an oval 32T is when doing a steep technical climb on loose terrain the power is transmitted more linearly and there is far less loss of traction...try it to see

[DieselnDust]

12 hours ago, guidodg said:

biggest difference for me on an MTB with an oval 32T is when doing a steep technical climb on loose terrain the power is transmitted more linearly and there is far less loss of traction...try it to see

That is very likely dependent on the amount of anti squat in the suspension. As the high spot and low spot on the chainring will alter the anti squat as the chain tension line of action changes. IME it reduces traction when I need it as the AS built into my bike is high. Newer bikes with lower AS may be less affected.

[jcza]

19 hours ago, swingTOpeddle said:

Shouldn’t it be based on a rider’s ability? Or would you suggest this for a 200 FTP person who’s 120kg also?

Comfortable shoes and you will walk at the same pace

[Jewbacca]

I reckon, without trying to break the internet, that one could look at it this way...

IF the oval is just marketing hogwash, is it WORSE that a round one?

If not, then who cares? It retains the chain and moves the back wheel.

The truth is, most people aren't remotely close enough power/fitness wise to eke out the 2% gains advertised as that 2% probably only happens at a w/kg avg way higher than most put out.

It's the perceived differences and preferences that people buy into. Like EZ grips. They are actually junk but people swear they are THE best grip out there.

Much like 32 vs 34... there is very little difference to the average cyclist as they will just adjust how they ride and their cadence to their gearing, not the other way round. 

If you're asking a public forum these questions, you are likely still nowhere near a finished product as a cyclist so if you go 32 you will likely develop slightly faster leg speed on the flats and if you go 34 you will likely start to become a top end grinder on steep climbs.

Realistically though it's trivial and doesn't matter

[DieselnDust]

<dashes to keyboard to google EZ grips>

[dave303e]

also horses for courses, at 4w/kg I am happy with a 38tooth for my day to day riding, because the area around the farm is so flat you can watch your dog run away for days. But I do have a 34 and 36 and swap them out when I know I will need them depending on where I am going to ride.

We did the same with enduro motorbikes, over gear for XC/harescramble and then shorten the gearing up for technical events

[117]

23 hours ago, madmarc said:

and analyzing my gear use on AXS app

Would you mind directing me to where I can get the same from my AXS app? 
Does it matter that I run a GX AXS? 

[Wyatt Earp]

On 12/10/2022 at 6:20 PM, Lukas Ferreira said:

Hallo 

i'm a novice on the mtb and I'm busy building a bike. What chainring is a beter all round for doing some weekend trails 

34T or 36T? I'll be pairing it with a 10 -52 cassette 

These are hard questions to answer without knowing the terrain you will be riding.

But as a novice my advice would be to put on a 32.

You will definitely be spinning out on the downhills, but then again leave that to the guys who feel they are winning the Epic.

 

You will be running the 10 as you say, even then it’s not an easy gear to spin out (there are guys who grind and think they are moving quick, but they normally get left behind)

Cadence is your friend, it’s not about ego and about who can turn the biggest gear, it’s about moving forward efficiently with the least impact on muscle fatigue.

Thats why people pull out of races like Attakwas, they would rather blame the heat than admit they went way too hard in the beginning with a gear their legs couldn’t really handle.

[100Tours]

20 hours ago, DieselnDust said:

The oval still pulls the same amount of chain through the dead spot as a round chainring.

That doesn't seem accurate?

if you draw a straight line between 2 non-adjacent teeth on a chainring then that would be a shorter distance than the line drawn along the curve. So you would pull less chain for the same leg movement through the part of the stroke where the teeth on the oval ring lie inside of the teeth on a circular ring.

Not commenting on the marketing hype, but your geometry argument is wrong.

[madmarc]

29 minutes ago, 117 said:

Would you mind directing me to where I can get the same from my AXS app? 
Does it matter that I run a GX AXS? 

You can download it from App store and Google play store

It works on all SRAM AXS models I run GX Eagle - its also used to set up your drive train

RD Micro adjustment

Configure how you want your shifter buttons to work.

Battery level

Firmware updates

BTW i have the AXS connected to my Garmin 520 as well - tells me what gear im in and warns me if the battery is low.

Every ride uploads to the app like Strava but gives you some analytics of drive train / rider / Route map etc etc - for me it's actually gives better info than the STRAVA free subscription 

Component summary from Northern Farms

 

Another from Modders

 

SBR on the 34T chainring

SBR on the 32T chainring - I hadn't changed the 34 to 32 in the app but it makes no difference when reviewing the time in each gear.

[117]

Thanks Mm. I have the app already, and used it to do some set up work etc. 

I'll fiddle with it this evening and see what I can extract