# 26 vs 29 gear ratio epiphany



## adamantane (Jan 27, 2005)

hey guys...i recently did an xc race and i couldn't understand why i was getting drop across flats and the hills...later it dawned on me that most of the other racers, probably all, were running 29 in bikes...so this morning i ran gear ratio calculations via sheldon brown's site using 175 mm cranks and a standard (or used to be) 3X9 drivetrain...so as you can see in the photo, two bikes with otherwise identical drivetrain save the wheelsize...across the board for every pedal stroke of the 29 in bike, the 29er will travel farther than the 26 in bike...i'm a diehard 26 rider only because it will require selling all three 26 bikes and buying three new 29 bikes...but the writing is on the wall, it will take more physical power for me to run a 26 bike and to keep up with a 29 in bike all else being equal....or am i missing something left out of these calculations....this will likely transfer to DH as well so that any chainring/cassette, the 29 bike travels farther per pedal stroke...maybe some of you already know this i'm always late to the party...but what do you think


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## Mudguard (Apr 14, 2009)

Smaller wheels shorten your gearing, bigger wheels lengthen it. I don't know if it requires more power. Bigger wheels are usually heavier too. So I would say it has more to do with the terrain. Perhaps the course was smooth with gentle gradient changes? Who knows? 
I would try do a lap on two identical bikes with the different wheel sizes and see which one is quicker


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## Le Duke (Mar 23, 2009)

It will take more power, yes, pedaling in the same gear, at the same cadence.

But, generally speaking, a 29er tire has slightly less rolling resistance than a 26er tire of the same pattern.

And, most people on 29ers aren't running the same gear ratios as guys on 26ers.

Really, power determines speed. At the same power output, a guy on a 29er will go SLIGHTLY faster than a guy on a 26er.


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## Gemini2k05 (Apr 19, 2005)

...or you could just make your gear ratio taller and have the same effect?

Is this post a joke?


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## adamantane (Jan 27, 2005)

that's a good point to change my gears, maybe run 24/34/42 if i can find them for my xc bike...idk i just never ran the numbers because i always scoffed at the new wheelsizes...but even changing to different gears means one has to use more power on the 26 to keep up with the 29er...


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## SHIVER ME TIMBERS (Jan 12, 2004)

time to get a case a beer, some hookers and pizza....become a Downhiller.....start shoveling jumps, and working on trails and drinking....then start gambling, drinking, more hookers, and pizza.....

XC race?? you kidding me....this is the dh forum....you are in the wrong place

want to start digging, drinking, and acting like a DH'er


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## Joules (Oct 12, 2005)

adamantane said:


> it will take more physical power for me to run a 26 bike and to keep up with a 29 in bike all else being equal....or am i missing something left out of these calculations....


take a physics class. Wheel diameter has nothing to do with power requirements. You got dropped because the other racers were stronger than you, not because of equipment (unless you were in your 44/11 and couldn't pedal any faster, which you and I both know, you weren't).


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## Deerhill (Dec 21, 2009)

29"er goes down SLOWER than 26"....it's like a whole extra slice


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## SV11 (Jan 2, 2011)

adamantane said:


> hey guys...i recently did an xc race and i couldn't understand why i was getting drop across flats and the hills..


You're joking right? You can't be serious.
The 3 posts above mine are on the money.
You got smoked because there were stronger riders than you also competing, take it like a man and don't blame the equipment.
When Sam Hill was beating the field by 5 seconds, 14 seconds... he wasn't riding some futuristic, gravity defying, exotic dh bike or a 29er, he was the strongest rider in the field whether he was on an Iron Horse or a Specialized.
If you don't like getting dropped, train harder.


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## adamantane (Jan 27, 2005)

ok ok, i just thought these numbers showed that for every pedal stroke, a larger diameter wheel moves farther than the smaller one...i'm not an xc person by any means, rather have dh viewpoint but the crowd here is hostile this holiday season!


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## Trasselkalle (Sep 5, 2014)

I agree with Shiver Me Timbers that you should post this in the XC forum rather than the DH/FR thread. Not very many here are interested in XC and those of us that are do it mostly because that's what we started MTB'ing with. 

As has already been elaborated on, wheel size rather than gearing makes up the in-practice difference. All racers have their own preferences for the gear ratios, so find one you like and stick with it. 

In terms of 26 vs 29, it can be clearly felt if you jump between 26" and 29" XC bikes. I have (and have had) a few similarly specced bikes with 26" and 29" wheels, and the 29ers are really nice once you're up to speed as they don't loose that speed as quickly when you hit pot holes and run over rocky/rooty parts. They are absolutely bigger and less nimble on technical downhill sections from the higher riding position though. They also aren't as quick up to speed again if you have to slow down somewhere. In practice, you can get used to both those things and I think most of the difference that I still feel is in terms of ride-comfort (smoother ride on a 29er) which over long rides causes extra fatigue. 

If I'd buy a new XC today, I'd easily go for a 29er over a 26er from a ride-comfort perspective alone. It's definitely not a night-and-day difference, but if you do much XC training/racing, any excuse to complain is usually explored as the pain level goes up and other are passing you... As a personal preference (i.e. has nothing to do with racing) I'd probably go for a tad slacker HA than my old ones as that also helps out riding downhill.


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## abelfonseca (Dec 26, 2011)

You just have to click your shifters to change your gearing. Am I missing something here??


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## SHIVER ME TIMBERS (Jan 12, 2004)

adamantane said:


> but the crowd here is hostile this holiday season!


 no it's like that every day....this is the DH, no wimp, skirt chasing, beer guzzling, gambling, steal your women and run up their credit cards and then leave them back with you crowd.


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## Thustlewhumber (Nov 25, 2011)

adamantane said:


> ok ok, i just thought these numbers showed that for every pedal stroke, a larger diameter wheel moves farther than the smaller one...i'm not an xc person by any means, rather have dh viewpoint but the crowd here is hostile this holiday season!


This is true... not sure what everyone was drinking when they made their posts...

Basically, a 29er rear wheel is like gaining 2 teeth on every rear cog. In single speed terms, 32/16 on a 26 is just like 32/18 on a 29er. If the 29er is also running 32/16, the 26 would need to be in 32/14, etc etc. They are not leaving you because they are making more power/you are running slower/etc... they are leaving you because they are inherently geared differently. Shimano/Sram didn't make "29er specific" gearing... they just slapped a 26" drivetrain on there.

The drawback is that a 29er wheel requires more torque to get up to speed, whereas a 26" wheel can spin up much quicker... although the 29er can maintain that speed much easier once it gets there. If you want to keep up, just shift up.


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## SV11 (Jan 2, 2011)

adamantane said:


> i'm not an xc person by any means, rather have dh viewpoint but the crowd here is hostile this holiday season!


You didn't post to gain knowledge, rather to make a point.
It doesn't matter what you ride and how it's geared, if you're not a strong rider, it's going to be the case no matter what you ride, why can't you take it like a man? Maybe then you can grow as a rider when you realize what you need to work on.
There are more drawbacks with going up in wheelsize than advantages when it comes to DH, it's just the way the cookie crumbles...live with it!


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## TheKaiser (Feb 5, 2014)

adamantane said:


> ok ok, i just thought these numbers showed that for every pedal stroke, a larger diameter wheel moves farther than the smaller one


They numbers do show that, but what you are forgetting is that it will take more leg energy to complete that pedal stroke on the 29er, for the very reason that it will move you farther.

Just shifting up a gear or 2 on the 26er will compensate for the smaller wheel and move you just as far with a pedal stroke as on the 29er, but then it will increase the energy requirement, also equaling the 29er.

Basically, any benefits of 29 vs 26 come not from the gearing but from the rolling characteristics relating to the tire/ground interface.

And BTW to those who aren't aware of it, Shimano and SRAM *do* make 29er specific gearing that is lower, thereby bringing it back down to 26er levels.


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## Trasselkalle (Sep 5, 2014)

As we're back to talking about which gear to ride on now, please also remember that your muscle build also affect which gear is the 'right' one. As tall gear as possible only works as long as your muscles can deal with it effectively. This is down to how you train and even how your body responds to training, and not just something that you pick during a race (even though an experienced rider obviously adapts all rides slightly based on how the body feels at each particular moment). If you have an easier time building stamina than muscle, you will be better served on a lighter gear and spinning more than others, and vice versa. Focus on your breathing and not what others are doing though! You ride XC to push your own limits as far as possible.


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## NWS (Jun 30, 2010)

You just discovered why some people use "gear inches" when comparing gearing on bikes with difference sized wheels.

Gear inches - Wikipedia, the free encyclopedia

And I'm pretty sure all those guys on 29ers were running smaller front rings than you or anyone else on a 26er. For exactly the reason you described. Which means that they actually had no mechanical advantage over you at all (pun intended).


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## Le Duke (Mar 23, 2009)

TheKaiser said:


> They numbers do show that, but what you are forgetting is that it will take more leg energy to complete that pedal stroke on the 29er, for the very reason that it will move you farther.
> 
> Just shifting up a gear or 2 on the 26er will compensate for the smaller wheel and move you just as far with a pedal stroke as on the 29er, but then it will increase the energy requirement, also equaling the 29er.
> 
> ...


No, they make cranksets and chain rings that allow the user to adjust gear inches to his or her preference. There are plenty of guys on 650B FS bikes riding 28t rings with 1x set ups, and plenty of guys on 29er HTs with 34t rings. Depends on what you can do.

Sent from my iPhone using Tapatalk


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## Thustlewhumber (Nov 25, 2011)

TheKaiser said:


> And BTW to those who aren't aware of it, Shimano and SRAM *do* make 29er specific gearing that is lower, thereby bringing it back down to 26er levels.


It's all generic gearing that carried over from 26" (22/32/44), but the chainring mounting hardware won't support lower gearing without physical modifications. If you go to a 20t low gear, it requires removing material with a dremel. If you go to a 28t or 30t middle, it requires special tooling on the chainring itself to make it fit. The 44t is just thrown away usually. The cassette itself is 11-36, but to be 29er "specific" it would need to be 13-38. I think they are rolling out 10-42 now, but it's 1x specific not 29er specific.


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## Terranaut (Jun 9, 2014)

I have 1 of each (26r-29r) 
When running XC the 29r is much faster, easier to pedal and smoother.
BUT
Downhill my 26r kills the 29r

The point is your question/statement or whatever has so many variables left out it makes no sense at all.
Are they all riding the exact same bike as you but with 29" wheels?
Other wise they may be faster because:
They have lighter bikes.
They have less rolling resistance tires (not just from size)
They have more air in their tires
They know what gear to be in
They are stronger
They have more endurance
They choose a better line
Should I stop now or keep the list going?

Your original post is like saying a person who is 225lbs weighs more than a person who is 200lbs...No kidding... really??
Big circles are bigger than small circles....Please tell me this thread is a joke 



...because it is .


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