Round vs Oval Chainring

[Quagga]

Sure not 50km/h and its rare to completely spin out but on tempo rides on gravel/tar I found I was missing the bigger gear and pedaling at a much faster cadence than what was efficient.

 

The 36 gave me a top end on my gearing that was much closer to what I had on my previous 2x10

 

If I manage to add a gravel bike to my collection sometime in the future I will go back to a 34 on the mtb.

So then you are on your own? or are you riding with people that still runs 2 x10

[Skubarra]

So then you are on your own? or are you riding with people that still runs 2 x10

 

I mtb with different people, weekends usually social rides on trails, during the week intervals/tempo rides with some fast buggers. Most of them are on 1x11 & 36 but not all.

[Frosty]

To the guys who say they "spin out" at what RPM do you "spin out" ?

 

In the groups I ride, we are doing the same speed so either we all "spin out" or we are in the 32 x 10 or 32 x11 (me in this have to do 8rpm more than the others)

 

So I am not sure where this "spinning out" happen you are talking about ?

“Spinning out” is like reaching terminal velocity. You’re spinning the legs but can’t generate anymore speed. Someone with a bigger gear will be able to reach a higher speed at the same cadence.

 

Here is my 5 mins at that cadence where I can no longer go faster.

[Zebra]

I spin out pretty much of the route from top of Suikerbossie past 12 Apostles Hotel, on a 2x setup; chainring is 36T, 10-speed cluster, 11T is hardest gear, so spin out on 36/11...

 

Going up to a 38T chainring, but yes, this is tar commuting, and HP slicks on an MTB...

 

I GUESS I SPIN OUT at AROUND 110 rpm, but no longer have cadence stats....

 

So, I am one who definitely spins out, incl around CapePoint, etc, but onTAR.

Cheers

Chris

[NotSoBigBen]

Just sitting here amused, you'll never have the prefect gear for ALL situations. Even roadies will sometimes 'spin out' but only you can decide what compromise you're prepared to make. On a 1x either you have a bad a$$ big gear and be part of the 'cool kids club' or you have a climb the wall type easy gear. Only by knowing what kind of terrain you mostly ride can you decide.... Its really not rocket science

 

You know like single speeders always say they 'always have the wrong gear' but it's their choice and they live with it

 

Round vs Oval... Like others I have only really felt that it helps with steep technical climbs where I seem to be able to turn the gear over and keep going easier, as far as the 'a 34 is like a 32 when climbing and a 36 at speed' not so much. Less fatigue not sure if makes so much difference I can out right state that it helps, not easy to judge.

 

A 34 oval is my go to gear on all my bikes, go figure

[ChrisF]

Who are you riding with and what gearing do they have?

All my rding buddies (all 4 of them ) run 1 x systems and I am yet to "spin out" but then again I can sit at 115 rpm for a while

36 to 11 gearing.

 

At 50km/h I am at about 115 rpm.

 

 

For me ... anything over 100rpm becomes uncomfortable, ie not sustainable for long periods. This around 40 to 45km/h is the useable limit for my setup. Yes, I would use a downhill to get the speed going, but on a few sections I can keep going at about 100rpm along the flats ...

 

Yes, this only happen on the tar sections from the trails, and then only on the downhills. As the route from my house to the trails is pretty much one long steady climb my return trip is only governed by traffic and safety ....

 

 

All this said, the gearing is spot on for the trails, and good enough for the rest

Edited March 26, 2021 by ChrisF

[The Ouzo]

[comic sans]

if only there was an online gearing calculator so that people could calculate speed/gear/rpm ratio

[/comic sans]

Edited March 26, 2021 by ouzo

[Quagga]

I mtb with different people, weekends usually social rides on trails, during the week intervals/tempo rides with some fast buggers. Most of them are on 1x11 & 36 but not all.

So they have mtb’s but ride road/ gravel????

[Quagga]

“Spinning out” is like reaching terminal velocity. You’re spinning the legs but can’t generate anymore speed. Someone with a bigger gear will be able to reach a higher speed at the same cadence.

 

Here is my 5 mins at that cadence where I can no longer go faster.

 

What is the rpm?

Lots of people say spin out. But don’t post rpm.

I have a friend that “spins out” at 95 rpm

 

That is spinning out in my mind. That is not training correctly

[TNT1]

if only there was an online gearing calculator so that people could calculate speed/gear/rpm ratio

Maybe that was tongue in cheek, but here you go:

https://www.bikecalc.com/speed_at_cadence

[DieselnDust]

True ! .But you only lift the weight of your leg on the recovery back stroke and all your weight again in the forward stroke when you walk. When you cycle with a round ring you are forced to use comparatively more power in the upstroke  than you would when walking .Round rings certainly make the hamstring muscles stronger .I alternate between both chainrings regularly .Oval rings always feel less heavy than the round ones .Probably because the power distribution is closer to walking .So round ones are really for aliens like Chris VROOOMmmm

 

 

Riiiiiiight can you pass me one of those joints too please

[Frosty]

What is the rpm?

Lots of people say spin out. But don’t post rpm.

I have a friend that “spins out” at 95 rpm

 

That is spinning out in my mind. That is not training correctly

As mentioned before I don’t have anything to measure cadence on my MTB. Online calculators would indicate using 34-11, 29-2.25 at 45km/h the cadence is 105rpm, at 47km/h it’s 110rpm and at max speed it is 115rpm. This is based on a negative gradient where freewheeling is not an option and bragging rights to get to the end of the road is the reward.

 

On a tar descent of a similar grade, I could easily get 5-10km/h faster owing to the better surface.

 

Edit: I know what cadence feels like, as 90% of my rides are done as a roadie with a PM giving that feedback. Except for structured intervals, where I need to stay within a defined power range, I don’t need to watch my cadence as it’s become second nature.

Edited March 26, 2021 by Frosty

[The Ouzo]

Maybe that was tongue in cheek, but here you go:

https://www.bikecalc.com/speed_at_cadence

on desktop it would have appeared in comic sans. 

I'll fix it for those not on desktop

['Kaze Pete]

if only there was an online gearing calculator so that people could calculate speed/gear/rpm ratio

If only there was a bloke called Sheldon Brown... [emoji848]

[Skubarra]

So they have mtb’s but also ride road/ gravel

 

fixed it for you 

[dasilvarsa]

So they have mtb’s but ride road/ gravel

During the Day in Gauteng you'll see a Hundred MTB's on the Road and Pavements before you see One Road Bike

except Early Morning 3-6 AM Then you'll see Hundreds of Road Bikes and Some MTB's.