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The Duuude, man...
3,533 Posts
(FAQ follows below)

29" Gallery

Short Rider, 29" Bike? Some good threads, please give us more links!

29" FAQ Thread : All you or others never dared to ask

The Great 29" Tire Thread
What tire where thread :

An attempt to list all TRUE 29" tires that ever existed (at 45 now, Sept 30th '07)

(proof that 2.5" bigger is not a big deal) Got to see :
World's first 36" Wheeled Mountainbike!

Where To Buy the 29" goodness? Shop listings, please add your 29"-friendly LBS

Top Threads Please nominate other top threads (multiple ones) in seperate threads to be added here. Don't let me come up with everything myself, thanks.
Big huckin' 29"er :

Loaner Thread for a 29" loaner near you. Dream to try, often in return for beer.

What the Independent Press writes about 29". Please request the mods to add articles worth listing here. Preferably permanent links.

History! Discussion on how 29" came to be.

Halfbreed FAQ! Trying to better the 29"er by adding a smaller wheel or the 26"er with a bigger one.


(Cloxxki totally replacing njc01's fine top post)
Okay guys, the time has come! We've been longing for a good FAQ section for years, and folks over on the Weight and Singlespeed forum they're posing with their super-duper FAQ's all over the place, we want to have that, too!

Here's the deal :
- Come up with a new question, and ask it in a reply
- If you can, answer a question, amend on it, or even answer you're own
- If you're really shy (don't want to ask a question all out in the open under a nickname), you can PM (personal message) me the question and I'll post it for you.

Once we've got most questions covered, njc01 will set up a neat html page with index, flashing icons, the works, to replace this thread and end up as an easy-to-skim FAQ section. Right, Nathan?

So, post up those stupid seeming questions! We all asked them before, and need to be asked to understand what we're dealing with here. After all, 10% more wheel on the bike, that's pretty complicating stuff!

Thanks in advance!

Happy trails, J

The Duuude, man...
3,533 Posts
Discussion Starter · #2 ·
Some Basic's

Question: At the most basic level, what is a 29er? How is it different from "regular" mountain bikes?
Answer: Good question. At the most basic level, a "29er" refers to a mountain bike with a larger rim than a "traditional or regular" mountain bike. The "29" is actually a bit of a misnomer, as it refers to the approximate diameter of the entire wheel (with a tire mounted), whereas a regular mtb is approximately 26" in diameter. To be more specific about rim size, the 29er uses rims of the exact diameter of a "regular" road bike rim also referred to as "700c." Continue to thumb through our FAQ section to learn all about the nuances of 29er frames, wheels, rims, forks, fads/fashions/paradigm's, geometries, parts, where to shop, brands available, availabilities, and the like.

Question: Do I need a special frame, or can I just sling a set of road wheels on my regular mtb and call it a 29er? What if I throw some bigger tires and a flat bar on my cross bike, is that a 29er?
Answer: We're on the border of splitting hairs with this question. Putting a 29er wheel on a 26" regular mtb frame would be problematic for 2 main reasons. First, unless you're fully disc, your brakes won't line up properly. The rim will be well above the brake studs for V-brakes, and therefore you can't use your brake pads. You can circumvent this by getting some special V's from Paul Components, but problem #2 will make that a not-so-good idea. Second, you won't have much (if any) frame clearance. Specifically, your tires will rub the frame and perhaps the inside of your front fork. IF you are able to get them to fit, they'll probably be so close that any mud or dirt would lock them up quickly. Cross bikes already have "road" sized rims, but you'll have the problem with clearance, the frames don't have the clearance for a true "Mountain Bike" sized tire. Further, cross frames are not optimized for off-road handling. The geometry is not suited for it, and many times (with some exceptions) the frame itself is not rugged enough to take true off-road use. I'm certain we'll have more FAQ's about frame geometry, tire choices, clearance, and the like, but at the most basic level, it's difficult and problematic to "Frankin-bike" a 26" frame into a true 29er.

Question: So any old set of road wheels will work on a 29er? Asked another way: Are road wheels the SAME thing as 29er wheels?
Answer: Kind of, but not really. The rim diameters are the same. However, at a basic level, the rear hub spacing (from frame dropout on 1 side to the other is usually 135 on mtb's and 130 or so on road bikes) is different making the hubs a bit different. Usually a frame can accommodate this difference between road/mtb hubs, but it is a difference. Next, road rims in general are not designed for heavy off-road usage. The rim itself also tends to be narrower, meaning it may be more difficult to hold a full sized mtb sized tire. There are many people who understand these limitations of using a straight Road wheel set and do it anyway. Specifically, people have had success with the Mavic Ksyrium's, various Zipp wheels, Speedcity's and perhaps others. Here's a 29er with the Ksyriums. This guy and others report no problems:

If you opt to build (or have built) a set of custom 29er wheels, the options are many, and often people will opt to utilize road, cross, tandem, or touring rims. For the most part, many of these options offer a stronger and slightly wider rim, which works very well for 29er applications. There are also a variety of 29er specific designs available which are driving the weights down to competive race-able weights even with a 29er sized rim. I am certain we will have several FAQ's on the topic of wheels, rims, availability, design, building, etc., so I won't labor those here.

Recovering couch patato
13,971 Posts
Question: It is just a Clydesdale thing, or is 29" for everyone?
Answer: For tall people, 29" can help bring things back into proportions, and this way also take away the disadvantages they suffer riding a bike with dispropotionately small wheels. With a properly designed 29" bike, they will be more stable in the saddle, even in extremely steep climbs and descends. The larger contact patch of the 29" tires helps them generate the grip and traction to keep up with lighter riders a bi more easily.
For short people, 29" offers the same pro's and con's. The con's of 26" mean less of a problem to them, but are improved upon anyway, while the con's of 29" (like weight), affect them a little more. People as short as 1m53 (5') are enjoying their 29" bikes, though under 5'5", it does take attention to detail in order to not produce toe-overlap (toe rubbing front tire when steering).

Recovering couch patato
13,971 Posts
Question: Quick and dirty, give me a list of 29" vs. 26", which wins where, concept-wise?
29" Pro's:
Rolling resistance (by some 10%)
Bearing resistance and wear (by some 10%)
Tire wear (by at least 10%)
Roll-over stability climbing and descending
Overall comfort over a ride
Grip and cornering balance
Pinch-flat resistance

26" Pro's :
Weight (300-400g lighter on the complete hardtail bike, all else being equal)
Due to this weigth advantage : faster acceleration, by around 2%
Wheelies are easier, the front lifts more easily.
Flickability in extremely tight corners (where walking would actually be faster)
Wheel stiffness, at least when using hubs of equal flange spacing

Recovering couch patato
13,971 Posts
Question: So, 29" rolls better over every type of bump more easily, right?
Answer: Actually, no. Some deeper (roll-through) bumps approach the 29" wheel's size so closely, that it almost remains stuck in them, making it harder to get through them. These bumps, in regular XC riding, don't occur very often, but every wheel size has it's critical bump size. A 36" wheel (it exists!) will just crash into a dirt jump ramp, where 20" will smoothly roll it up, closely following the curve of the ramp. In regular XC, with roots and rocks, a larger wheel in 99% of the instances means you roll over it with greater ease, fewer energy loss, and therefor faster. Brake bumps made by 26" wheels seem like minor bumps when rolling over them with 29" wheels which don't pick up that resonation frequency. By the time everyone rides 29", the bump frequency will probably become 10% lower. This, and the idea that with 29" you can brake later, will reduce the number of brake bumps before a corner. How that rides exactly, a the point this FAQ is written, probably no-one ever even experienced.

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13,971 Posts
Question: I think I'm all set now with my new 29" rig, I simply love it. Now, tell me which tires to get for which circumstances. Back in my 26" days, I had tires for everything : sand, mud, hardpack, street, etc.
Okay, some popular choices. All are over 1.9", thus truely 29" :
Mud : Kenda Klaw XT, IRC Notos and Mythos, Continental Vapor
Fire roads : WTB Nanoraptors, Bontrager ACX Jones, IRC Notos and Mythos
Rocky : WTB Motoraptor, Bontrager ACX Jones
Hardpack/Grass : Bontrager ACX Jones, WTB Nanoraptors
Sand : WTB Nanoraptors, Schwalbe Big Apple 2.35" (option for rear only)
Street and beach : Schwlabe Big Apple 2.0" or 2.35", Kenda Khan
Trekking and ultra-long distance allround dry surface : Kenda Khan

Recovering couch patato
13,971 Posts
Question: You got me all curious now! Where to get my taste of that 29" action, got one I can borrow or something?
Answer: Starting point for most will be the world-wide spread Gary Fisher dealers, the better part of them have 29" bikes for testing purposes, they're even listed on . For Europe, Nishiki dealers are an option as well. You could post on your local (MTBR) forum or even the 29" forum to ask for a testride, 29" riders are often ready to help a fellow rider out. State your location and body length, and you're as good as set.

Recovering couch patato
13,971 Posts
Question: I love my 29" bike, but not every shop yet carries spare tubes. I guess I better just ask for a road tube, as it's already the 700c size? It's made to stretch, right?
Answer: Correct, rubber stretches...till it tears. Using narrow tubes in a 29" tire would be like using a balloon in a football. The tiniest needle that passes the outer layer will make it blow. If purposely designed 29" tubes are unavailable, better first opt for 26" tubes that are meant for slightly wider tires, for instance a 26x2.2-2.5" tube for your 29x2.1" tire, to make up for the 10% larger 29" wheel. Some slight of hand, or just one extra hand from a riding buddy, will mount it up pretty easily, reliably, and be very affordable. 700c x 45mm tubes have been reported to work, but also to unannouncedly blow like a shotgun. Of course, these 45mm tube are not made to work for anything bigger, and why should they, 29" simply never existed before!

The Duuude, man...
3,533 Posts
Question: 29er's sound good, but there's not any choices for Frames or bikes, right? I mean, there is no way to have a different bike, every one is riding the same 1 or 2 bikes that are available, right?
Answer: No, there is a surprising number of frames and bikes and builders out there doing 29ers. Here's the "short" list in no particular order. I'm sure I missed several: -- Asylum (House branded Titus RX in Aluminum) (see Sofa Kings) (broken?) (Sofa King link in upper right) (limited I think) (not in thread but since they make Gunnar…) (not in thread but since we've seen 29"er Racer-x pics…) (not in thread, will they do custom?) (not in thread, will they do custom?) (not in thread, see Atlantis model)
Voodoo Cycles
Nicolai[email protected]@.efda0de
DaVinci 29" Tandems[email protected]@.efd9dc2

Cloxxki 20-4-4: I added and edited some

Recovering couch patato
13,971 Posts
Question: Since 29" seems to use road size rims, I guess it also rides much like a road or cyclo-cross bike, mostly useful for fast, smooth, LAME courses, huh?
Answer: Wheelsize affects ride characteristics for sure, yet BMX share the wheelsize with many folding bikes and even recumbents, so it's not exactly all-decisive. 29" owners say they like the way their bike allows them to ride up climbs they before were forced to walk, and ride down stuff they'd before would dare or just hike-a-bike. The severely improve stability (over 26" bikes) for most means that 29" allows them to ride more agressively and cross more extreme terrain more easily. Big rims = speed, fat tires = extreme. The combination of both opens up new riding oppotunities, and to it's users : more, bigger grins..

The Duuude, man...
3,533 Posts
Discussion Starter · #11 · (Edited)
Fork FAQ

Question: What about forks? What forks are available? Are they any good?
Answer: Well, if you went rigid, there is no limit to the fork options, Ti, Steel, Aluminum, custom, whatever you want. This rigid/suspension question is another FAQ altogether, so here I'll focus on availability of suspension forks.

There are two mainstream fork companies serving the 29er community, and various smaller/more obscure companies also offering alternatives.

Marzhocchi: They have a long tradition of great forks, and they have adapted their flagship XC fork for 29er use. First, they took their Marathon SL and put it in a 29er package. This is what Gary Fisher bikes feature(d) on their top of the line 29ers (Supercaliber and Sugar 292). This fork offers many adjustments, and is a highly capable and race-able fork. Second, they also adapted their MX fork for 29er use. It's a great basic fork that will take everything you can dish out, no question. It's a great choice for watching your spending when trying out the 29er for the first time.

White Brothers: They have a very long tradition of high quality in the suspension fork market, for bicycles and motorcycles. Long before Fox Forks starting putting out their 32mm sanction tube bicycle forks around 2001, White Brothers was quietly putting out some of the best, lightest, stiffest, most durable and serviceable forks on the planet. Starting before any other major fork manufacturer, they used this same high quality products, mentality and world class customer service to offer the first major suspension fork for the 29er application, the CX-1. This is still a fantastic fork and while not currently available new, they can be easily had very cheap on ebay. It is certain that this fork is the best intersection of performance, lightweight, and value to be had - anywhere. In 2003, WB came out with two updated versions and called them the BW .8 and BW 1.0 (with 80 and 100 mm travel respectively - with the 1.0 being adjustable from 80-100). The .8 is air and the 1.0 is coil. These forks, with the 3.4 pound .8, put 29er forks on par with any existing fork on the market, 29er or otherwise. While they utilized a low-volume, high-pressure design, they also had features such as external rebound and compression dampening, lockout, and of course disc compatibility. For the 2004 year model, they changed to a high-volume/low-pressure system, which further refined the ride so that you have a stiff fork with buttery smooth action, with all adjustments external (as an FYI, you can send your 2003 .8 in to WB, they will retro-fit it with the 2004 internals, and your fork will be a literal identical twin to a 2004, so find a deal on a '03 and send it in…cost is around $75). There is no finer fork to be had. The '04 BW .8 weighs in around 3.4 pounds, which is excellent.

Winwood: Not a lot is known about this fork. It does come in an Air or Coil Spring versions. It appears to be very nice, lightweight, has carbon materials, with disc compatibility. We don't have a review at this time. Once one is available, site will be updated. They will have significantly lower prices, so if performance is good, it will be a strong contender for the price conscious market. The air fork is around $290, with the coil around $240.

Here are some representative photo's of some of these forks:

Here are photo's of some the major forks:

2004 Marzocchi Marathon SL:

2004 White Brothers BW 1.0:

2004 Winwood DeeDee Carbon 29er:

Recovering couch patato
13,971 Posts
Please, if you have some time to spare, help us out and add a question/answer or PM me a list of Q's. Thanks in advance!!!

Question: So I understand I can't just swap out wheels and frames of 26/29" size. Then what's so different about the 29" frame? I don't see it!
-Canti mounts, if needed, are placed 31.5mm (half of difference in rim diameter) further away from the wheels' axles.
-The rear triangle offers some extra room for the larger wheel.
-The bottom bracket is lower compared to the axles, to end up with a typical BB height for the intended type of riding.
-To compensate for the higher front axle and longer fork, head tubes are often on the short side. If not, the handlebars may end up pretty high. This counts especially with use of a suspension fork, which of course is longer than most rigid forks.

Recovering couch patato
13,971 Posts
First question from our viewers! Please don't hesitate to call us on the above number! without your calls, this good thing cannot take shape!

I'm new the 29er scene. Should I expect to have about the same standover height on a 29" bike as on a 26er for a given effective TT length? If not, how much less standover am I likely to be looking at?

Answer: (long version)

Standover height is often measured on the top side of the toptube, right in between head tube and set tube.
Let's say your new 29" bike has the same BB height as your old 26" one, and also the same seat tube length. So one of the 2 points on the new 29"er is already identically positioned as you're used to. All the height increase (hard to prevent it) up front, therefor, will count for half to the standover height increase.
So what really doesn happen up front?
Well, with the identical sag and travel (assuming suspension), your fork will have to be some 31mm longer, to accomodate the 29" wheel. This 31mm, corrected for some 68º angle between headtube bottom and axle, is worth some 29mm vertically. With the front axle sitting 31.5mm higher, the total is about 60mm. This leads to a 60/2=30mm higher standover height, at least, when using the same headtube length as one the 26" bike. But, because you probably want your bars in the same position as before, you'll try to spec a headtube 60mm shorter. 60mm less is sometimes hard to make in a proper way, so if you can't lose more than 40mm, your standover rises some 20/2=10mm. Actually, these 20mm should be corrected with the ~72 headtube angle, but whose counting loose mm's?

Not all 26" have the stem seated directly on top of the headset, so running your 29"er spacerless can help bring the handlebar right there where you need it. For some, 29" will allow them to leave their riser bars,a nd go to flat. Some will go from a 15º stem to a 5º one. It's all about whare you're from and where you're heading.

As you hopefully now understand, all choices and measurements on your new bike together bring you to a new standover height. All in all, excluding extreme exceptions, standover on a 29" will not HAVE to be much higher then you're used to. Bikes such as the Surly Karate Monkey, where the choice was made to have a tall seat tube for a retro look, standover, as expected, is significantly higher than with a 26" rigid racer hardtail.

Answer: (short version)
With proper frame design, done to minimize 29" standover, there's little reason to have an average standover to rise more than 10-20mm, even though the wheels themselves are 63mm taller.

Recovering couch patato
13,971 Posts
Question: Woooow, dude, those wheels are massive!! But I guess you can't build a decent light bike with them, right?
Let's first set some ballparks standards for a typical race-worthy 26" bike, with it's 26"-specific parts.
Rims : 425g a pice, 850g total
Tires : 500g a piece, 1000g total
Tubes : 130g a piece, 260g total
Rim strips : 15g per wheel, 30g total
Spokes : 350g
Fork : 1500g
Frame : 1700g

Rims, tires and tubes all only need to be 10% bigger, thus 10% heavier.
Weight penalty for rotational weight : 214g

Spokes, let's say those are 13% longer, but in the thinnest part, so still 10% heavier : 35g penalty

Frame : needs longer chainstays, longer downtube, but much shorter headtube : zero penalty
Fork : only 31mm longer, in realily (Whitch Brothers otherwise identical 26" vs 29" forks) 60g

Chain will be probably have to be 2 links longer due to longer chainstays, but then again, one can ride with a smaller chainring. Overall : zero penalty.

What did I forget?

Total 29" vs. 26" penalty for this example: 309g. Compare this to a 10% rolling resistance advantage. Rolling resistance is between 40 and 80% of the total resistance to overcome in XC riding, so the weight penalty (3% on a bike and around 0,4% on rider+bike) seems only like a detail in comparison.

At the time I'm writing this, 24-4-4, no tue big meat 29" tire under 560g is actually available in shops. The 560-570gg Bontrager AcX Jones 2.2", though, has an agressive tread, still lots of room for future weight savings in semi-slick race tires. as the industry embrases the 29" tire more and more, we'll hopefully see more tires to even put the standard 10% on 330g race-only tires such as the Maxxis Flyweight 330 or the Continental Twister Supersonic.

Recovering couch patato
13,971 Posts
Another good Q from my PM box (you can also just reply in this thread, I'll take away the question when someone answers it).

Question: I am considering discs for my Sugar 293. Since the wheel is 10% larger, do my discs need to be 10% larger like a 7" or 8"? I do weigh 240 lbs.
Answer: Disc brake power is a result of rotor/wheel diameter. More is better. Indeed, 10% larger ones are needed to obtain the identical power to ones used with 26" wheels. Still, the added traction of the 29" wheel may for some make 160's still acceptable, and who says 160mm is just enough for 26", and not already overkill? But anyway, if ou want your discs to feel like the same ones on the 26" bike, go a size bigger on the rotors!
By the way, the 29" wheels do not affect heat buildup, decelleration is decelleration, heat conduction is heat conduction. So if you match the rotors to your 29" wheels, as a bonus you actually improve the heat-buildup characteristics over the 26" small-rotor setup.

Recovering couch patato
13,971 Posts
From the PM box, related question to one on the first page :

Question: I want a 29er sooo bad. Do you think a person that is 5'10", or normally rides a 17.5 MTB bike is too short for a 29er?...whats the smallest 29er you can get?
Answer: A ladyfriend of mine is 5'9' and did a testride on a Fisher Medium, it fitted perfectly. Fisher also makes a Small... Okay, the Medium is 17", the Small 15", and a framesize is worth about 4" (twice the leg difference, Michelangelo). Theoreticizing, a 5'5" rider would still be perfect on a small, and not even on the lower end of the range yet. At 5'10", you can do weird things to geometry and still be okay on a 29"er.

Question: I am thinking about selling one of my bikes for money for a 29er. Is this a good idea?
Answer: Financially, I can't think of a better way to finance a new bike and not over-crowd the bike room at home. If you've already decided you want it bad, you need to decide if you want it badder than your present bike. Ask around, on our forum even, for locals with 29"ers that will fit you, and get yourself hooked up for a testride amongst good people. You'll be able to make a decision based on experience, not on our enthousiasm you've been caught in.

The Duuude, man...
3,533 Posts
Discussion Starter · #18 ·
Question from Buster

Buster's Question:Is there a way to modify standard V brakes (ie for a 26" wheel) so that they would fit 29" wheels mounted in a standard MTB frame? Or is there a manufacturer who makes suitable V brakes? I checked Paul Components but at $115 this seems a little steep![/QUOTE]

Answer: There is no known way of making regular v-brakes work on a 26" frame with 29" wheels. I can see you already read my FAQ about that above, and you checked Paul's Components...Paul has some sweet stuff, that is for sure, but yes, they are quite spendy.

If you have a steel frame, you could have the brake mounts moved up the frame and re-welded on there. Some places, such as Walt's bikes will do this king of service relatively cheaply. But then you still have to do the front fork, which will be impossible if it's a suspension fork, but possible if its a rigid steel fork. However, these are both still not recommended, becuase your tire clearance will be horrible, you'll not be able to run full sized meats, etc, and by the time you paid for shipping both ways, and the service, you'd have spent more than the pauls brakes, and still have the clearance problem.

I suspect your concern, and most people's about coming to the 29er community is this: I don't know if I will like it, so I don't want to spend a boat load of money trying it out. This is a valid and very common concern. Afterall, if you wind up hating it, you don't want to be out $2000 bucks for a custom Ti hardtail. so far, I've never even HEARD of anyone not liking it (qualifier: anyone who has seriously spent some time in the saddle and given it a fair shake...1 time I had a guy -- a buddy in fact -- ride my Monkey in a parking lot for 2 minutes and denounce all 29ers as slow and heavy).

2 Suggestions:

1) Try to find a shop or buddy, or mtbr member in your area who will let you really test ride a 29er. Get a feel for it, realize it's the way to go, and then you'll feel better about commiting.

2) Try to find a used Surly Karate Monkey, either as a whole bike, or as a frameset. They are dirt cheap, and come with a rigid fork, so basically all you need a road bike sized wheelset and your 26" wheeled parts, and you're off an running.

You'll like it, you won't go back.

mtbr member
455 Posts
Good points, ncj01 and Cloxxki. When I started writing I couldn't stop, so forgive me for repeating issues you have already covered. Please pick any fragments you might want to use, and ignore the rest.

Why bother about wheel size?
What are the effects of wheel size?
Can I go faster with bigger wheels?
Is stability better with big wheels?
Is grip different?
Is energy better preserved with big wheels?
Is the need for suspension less with big wheels?
Are big wheels more comfortable?
Why is safety claimed to be higher with big wheels?
Are big wheels only for big people?
What type of riding are big wheels for?
What measure is the wheel size referring to?
Which bike parts are wheel size specific?
Are 29" wheeled bikes expensive?
Are big wheels heavy?
Does wheel size affect gearing?
Does wheel size affect braking?
Does wheel size affect maneuverability?
Are big wheels weaker?
Are all wheel sizes legal in races?
So, should I go 29"?

Q: Why bother about wheel size?

Your mountainbike's wheel size affects how you ride. It affects how efficiently you can ride in off-road terrain, and it affects the bike's handling. It affects your ride's entire feeling.

Most stock mountainbikes come in a handful different "sizes", by which all have the same wheel size. You can typically not change a bike's wheels to others of another size, since the entire frame geometry depends on the wheel size. Bigger wheels will generally not fit, and smaller wheels will have you strike the pedals to the ground. Therefore your very first step when choosing a mountainbike should be to decide which wheel size you want.

The effects that wheel size has to your ride can be described by their nature. It is then much up to you to value these effects, depending on your preferences and priorities.

Q: What are the effects of wheel size?

From off-road, cross-country riding point of view, big wheels are different from small wheels in two important technical aspects: The angle of attack for the wheels against obstacles is smaller, and the contact area with the ground is longer.

Those two differences translate into a number of real riding benefits, depending on your type of riding and what is important to you. The benefits are higher speed capability, better stability, better grip, better energy conservation, less need for suspension, higher comfort, and a safer ride.

The main benefit with small wheels is that they make it easier to design a frame for a small person.

As a first illustration of the different benefits of big wheels and small wheels, you may try to imagine an adult riding with 12 inch wheels off-road, or a child learning to ride with 29 inch wheels.

Q: Can I go faster with bigger wheels?

Bigger wheels roll easier over rough terrain. That is probably the most important benefit with bigger wheels. Some go further and say "big wheels roll easier on flat ground also", but even if there may be some truth in that, it is not equally intuitive and general scientific evidence is yet to be seen.

One reason that bigger wheels roll easier over rough terrain is that their angle of attack towards obstacles, small as big, is less. Put in other words, they are not as hindered by stones, roots, and rough ground as small wheels are. Another reason to the lower rolling resistance may be that they due to the longer contact area with the ground are staying on top of the ground better - the deeper you sink, the more speed you lose.

With easier rolling, or lower rolling resistance, it becomes possible to ride at higher speed since more of your power output is available to increase speed when less is needed to overcome rolling resistance.

The benefit with low rolling resistance may very well be underestimated in off-road biking. There are few studies on rolling resistance for different MTB tire types, materials, knob patterns, air pressures, and wheel diameters, and even fewer that also takes into account real-life terrain types and variations. Weight, by comparison, has in the bike business a tremendous focus, which might be simply because it is so easy to measure, although the realistic effect of a weight difference at off-road riding is not by far equally straightforward to try to determine. Many riders are positive that the lower rolling resistance of big wheels helps them go faster much more than any weight savings do.

Can we accurately quantify this advantage in rolling resistance? Probably not. Again, any derivation attempt quickly gets complex. Nevertheless, there have been some tests with tires rolling against one single surface (such as asphalt or steel), actual bikes rolling down a hill, or people riding with measuring devices for heart rate or oxygen consumption. These tests may all provide numbers, but those sure will be prone to be questioned.

Q: Is stability better with big wheels?

Bigger wheels have a longer contact area towards the ground, and they tend not to bounce as much on rough ground due to their lower angle of attack to obstacles. As a result, big wheels are perceived as more stable than small wheels, especially on rough terrain. Such higher stability provides better comfort and a safer ride, and may allow higher speed.

Q: Is grip different?

Again, bigger wheels have a longer contact area with the ground. Some feel that they get a better grip that way, enabling them to corner, brake, climb, and accelerate faster and more confidently.

Q: Is energy better preserved with big wheels?

The rider is going to be able to preserve energy better because bigger wheels roll with less resistance, less vertical oscillation, and less abrupt hits. Less rolling resistance spares your power output. Less vertical movement and less abrupt hits spares not only your arms but your whole body. This is particularly advantageous at long-time riding, such as in marathons and 24-hour events.

Q: Is the need for suspension less with big wheels?

Many riders are feeling that the smoother ride of bigger wheels allows less suspension. For example, among riders with 29 inch wheels, some are choosing hardtail instead of full-suspension, some are comparing an 80 mm 29" fork with a 120 mm 26" fork, and some are feeling that a rigid fork is a smoother ride with 29" wheels than with 26" wheels.

Q: Are big wheels more comfortable?

The ride is more comfortable with big wheels for the same reason as why energy is better preserved. The bigger wheels are not hitting rocks and roots as hard as small wheels do, because of the smaller angle of attack. Also, the bigger wheels are not finding their way as deep down between every rock and root and into every cavity, as small wheels do. As a result, the rider will not have to work as hard with arms and legs, acting as springs, for smoothening the ride.

Q: Why is safety claimed to be higher with big wheels?

Higher safety has been brought up as an advantage with 29 inch wheels. A couple of reasons why some feel safer with them, may be that the bigger wheels roll more stable and are less prone to be abruptly halted by obstacles, making it less likely for the rider to go over the handlebars.

Q: Are big wheels only for big people?

Everyone can experience the benefits with bigger wheels. That is what we all do several times during our grow-up, when we step up from 12" wheels to 16" wheels, from 16" to 20", and so on. The maximum practical wheel size is mainly determined by your body size. You must be allowed to sit in your preferred position and still have enough space for your desired front fork and enough clearance between feet and front wheel, to name a few aspects. The biggest size mountainbike wheel commercially available today is 29 inch. There is no exact minimum rider size for which 29 inch wheels fit, but there are size Small (around 16" frame size) production mountainbikes with 29 inch wheels, and short persons saying they fit them well, and custom frames in even smaller sizes.

Bigger people seem to be over-represented among riders with bigger wheeled mountainbikes. Consider that the height of a 180 cm (5'11") rider is proportionally to 26" as the height of an average height 165 cm (5'5") rider to 24" wheels, and then ask yourself how many average size riders choose 24" wheels for mountainbiking. Some claim that just looking at the proportions of an extra-large frame with 26" wheels says something.

In terms of body properties, not only the rider's height is important when choosing wheel size, but also the weight. Heavier riders have found the bigger wheel longer contact area with the ground give them better support, just like a heavier person benefits with longer skis.

Q: What type of riding are big wheels for?

Most of what is said here regards general off-road riding. Considering the properties of bigger wheels, they would certainly seem to have some benefits also in hardcore downhill riding, at least for the front wheel. For general-purpose street or commuter bikes, bigger wheels than 26" have since long been common, and in many parts of the world even the norm.

Q: What measure is the wheels size referring to?

"29 inch" is a mountainbike marketing denomination, a label, for tires and rims with 622 mm bead seat diameter. Another, much older and more common label for the same diameter is "700c", which is used in the road bike world. Yet another label used for the same bead seat diameter is "28 inch", which is used in some countries for street and hybrid tires. Thus, ISO 47-622 (47 is the width in mm), 700x47c, 28x1.85", and 29x1.85" are theoretical different denominations for the same tire, fitting "29 inch" rims. The labels "29 inch" and "700c" do not specify anything about a rim's measures other than the bead seat diameter, such as width, height, or intended brake type. You will need to find that information separately.

The "29" in "29 inch" refers to an approximate outer diameter of a typical mountainbike tire labeled about 2.1" wide. With a 2.1" mountain bike tire being about 55 mm tall from the bead seat, the actual outer tire diameter is (622+55+55)/25.4 = about 28.8 inches. Similarly, "26 inch" is a label for 559 mm bead seat diameter rims and tires. With the same tire height, actual tire diameter is (559+55+55)/25.4 = around 26.3 inches. So the difference between "26 inch" and "29 inch" is in reality two-and-a-half inches.

Q: Which bike parts are wheel size specific?

The parts that depend on wheel size are frame, fork, rims, tires, and tubes. Add spoke and rim tape length to be specific. Then gears and brakes may also be chosen different size, but they are not "wheel size specific" in the same sense.

Q: Are 29" wheeled bikes expensive?

Price is higher for 29" wheeled bikes, because the 29" specific parts are still made and sold in much smaller quantities than their counterparts for 26" wheeled bikes. So you are likely going to have to pay more for an equal-quality equipped 29er, or accept some lower-level components for a given amount of money.

Q: Are big wheels heavy?

Weight is a common objection to bigger wheels. So how much extra weight are we talking about, and how big effect does it have?

As an estimate, the weight difference between one 29" wheeled bike and one 26" wheeled bike with some kind of similar component quality level, can be over 1000 g for low-end bikes but doesn't have to be more than 500 g for high-end race bikes. The difference is expected to decrease, since there are yet no hyper-light versions of some of the 29" specific parts. The geometrical differences in frame, fork, rims, tubes, tires, and spokes, call for a theoretical, overall race-weight difference of about 300 g. To put this in perspective, the total weight for bike plus rider is around 90,000 g with an average 80 kg rider.

Another reason why 29 inch wheeled bikes tend to be heavier than the 26 inch counterpart is that the 29" specific parts are more expensive due to the smaller market and production volumes. Since they are more expensive, a given amount of money that could buy you a high-end, lightweight 26" part may sometimes only buy you a mid-end, heavier 29" part.

Some people are worried about the fact that most of the extra weight is in the wheels, increasing "rotational weight". All bike weight, rotational and non-rotational, affects your ride in two major aspects: acceleration and climbing. Additional weight in tires and tubes counts from acceleration point of view as an extra approximately 90% compared to "fixed" bike weight and an extra 70% for rims, but just as any weight from climbing point of view. But of course if you accelerate at a climb, there is still the acceleration penalty. For example, a 50 g heavier tire affects acceleration as much as 95 g on the frame does. Whether that heavier tire is 26" or 29" doesn't matter - it is the weight that matters, not the diameter itself. Another example: when climbing at constant speed, an extra 50 g in a tire feels exactly as much as an extra 50 g on the frame does (there is no constant speed riding is real life, but close).

So what practical effect does this extra 0.5% rider-and-bike weight have? The theoretical answer seems to be, from calculations on simplified conditions, that it would slow your race time down a number of seconds...if you didn't have the 29" wheels rolling advantages.

As a last note on weight, the same extra energy you need to put into a heavier bike to get it up to speed, may then help you keep that speed. It takes more to brake a higher momentum, which may then help keeping speed over rough ground and at downhill sections.

Q: Does wheel size affect gearing?

The distance that you travel by one pedal revolution depends on the front ring, the rear cog, and the rear wheel diameter. A 29 inch wheel has about 10% bigger outer diameter than a 26 inch wheel, with average 2.1" tires, resulting in a "heavier" gearing if you would run the same front ring and rear cog. So with 29 inch wheels and a standard derailleur drivetrain, you will, maybe without thinking about it, either be using the granny ring a little more often and the big ring a little less, or tend to use a little bigger rear cogs. With today's 27 gears, the difference has little practical effect - you "lose" your lowest granny gear and get one even higher top speed gear. However, when you are getting into special setups like only one front ring or two, you will want to take the difference into account.

For singlespeeding with 29 inch wheels, you simply need a 10% smaller front ring or a 10% bigger freewheel to get the same gearing as compared to a 26 inch wheeled singlespeed bike.

Q: Does wheel size affect braking?

Braking depends on wheel size, because the wheel size affects the ground contact area, the braking leverage, and in some setups the heat-up and wear. Some say they feel a difference in braking characteristics between 29" wheels and 26" wheels, while some feel that the theoretical differences is overshadowed by aspects of brake type and setup.

The contact area with the ground is longer with bigger wheels, which some feel allows harder and more confident braking. This is hard to quantify, due to an infinite number of different combinations of surface, tire, and velocity, but might just be more significant than the difference in leverage.

Better leverage means that you don't have to pull the brake levers as hard to achieve the same braking effect, or speed reduction. Less leverage does not mean that you will not be able to brake hard enough, though. A rim brake is relatively a little closer to the wheel periphery on a bigger wheel, while a disc brake is relatively closer to the hub, given the same disc diameter. With 29" wheels and rim brakes, leverage is a few percent better as compared to with 26" wheels. With 29" wheels and disc brakes of same diameter, leverage is about 10% less. If you prefer, you could go up one disc diameter size, which would make up for the less leverage and as a bonus give extra-low disc heat-up and wear.

With the 10% higher mass of 29" rims, given same rim profile as a 26" rim, the heat-up and wear is 10% less. Heat-up and wear with disc brakes, on the other hand, is independent of wheel size.

Q: Does wheel size affect maneuverability?

Maneuverability is, besides weight, a common concern with those who hesitates going to bigger wheels. It is the bigger physical size, and perhaps also the longer contact path with the ground, that some believe would have an adverse effect on maneuverability. The contact path with the ground is indeed longer, and the wheels are about 10% bigger.

Some who are used to a 26 inch wheeled bike and have taken a test ride on a 29 inch wheeled bike, have claimed to have experienced a worse handling in tight terrain with the bigger wheels. Yet others claim the opposite - that their 29 inch wheeled bike is actually easier to handle in all types of terrain, let alone trials-style trick riding, due to better stability and support. Perhaps rider size again has something to do with it, and what you are used to.

Q: Are big wheels weaker?

Big wheels may be weaker than small wheels, especially if the number of spokes and overall construction is the same. For that reason, one would perhaps want to use 32 spokes instead of 28, 36 spokes instead of 32, and so on. However, big wheels take less hard hits due to their smaller angle of attack to obstacles, reducing the need for more spokes. In reality, many riders seem to use about the same number of spokes on their 29 inch wheels as would have been normal on a 26 inch wheel, and it has not seemed to be an issue.

Q: Are all wheel sizes legal in races?

All wheel sizes "no bigger than 29 inch" are allowed under UCI mountainbike rules. Until the end of 2003 only up to "26 inch" was allowed, for a reason that seems to be known by no-one.

Q: So, should I go 29"?

There is no guarantee that a 29" wheeled bike is the best for you. Everyone has got his or her own priorities and type of riding. It is up to you to ask yourself what is important to you, and to judge what you believe and what you do not believe, with or without test riding.

Premium Member
7,591 Posts
Why NOT to move your canti posts

First off, it's Waltworks, not Walt's Bikes.

Second, there are VERY few 26" frames out there that will accept a 29" wheel with any kind of mountain bike tire at all. You can get a decent sized (~40c) cyclocross tire on some frames. But it's not worth the expense or difficulty.

I second the Karate Monkey recommendation. And you can also find some builders (like me) who will build you a bike with straight-gauge tubing for relatively cheap if you want to try something a bit different. The Karate Monkeys are mostly straight gauge .035" 4130 tubing - which costs in the range of $3-4 a foot. Very cheap, surprisingly rideable. Expect a 6 pound frame, though.

If you're REALLY on a shoestring budget, get a non-suspension corrected rigid fork (410-425mm crown to axle works pretty well) for your 26" bike and put on a 29" front wheel. It's easiest if you have one with disc tabs (no worries about the brakes reaching the rim) but you can also bolt on a bmx-style v-brake adapter (available from places like Dan's Comp) which only costs $10 or so. Ugly? Yes. Ghetto? Perhaps. Functional? Completely.

The handling characteristics with this setup are not the full 29" experience, but it'll help give you some idea of what 29ers are all about. You can actually keep your bb drop, head angle, and general handling characteristics pretty decent doing this, though your mutant 26/29 bike isn't going to earn you any admiring looks at the trailhead.


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