In the realm of full suspension, a 29″er long travel full suspension bike seems like it might possibly be a not so good idea. Many poo-poo the concept and point to wheel strength, wheel diameter/geometry issues, and increased mass as the big problems with doing a 29″er long travel bike, amongst other concerns.
One of the “solutions” to solving the big wheeled long travel conundrum that has been proposed is to use the old French touring bike wheel, the 650B. It has been offered as a wheel size that will give a “big wheeled benefit” without the headaches associated with designing a 29″er full suspension bike. This post will seek to show why I believe this “solution” is not going to work. Let’s take a look.
Could this be a fore runner of a 650B long travel bike?
Well……actually they already tried it!
At Interbikes Outdoor Demo, I was able to test ride two 650B wheeled mountain bikes. One of which was an experiment by Haro using one of their long travel 26″er bikes retrofitted with 650B wheels and tires.
Here’s my take on it: I have ridden the above pictured 650B FS bike which was a great bike, but for all the world didn’t really do much for me from a “big wheeled” standpoint. I feel that with 5 plus inches of squish on board, you are going to have a really hard time distiguishing whether it was the tire that made that bump easier or was it the suspension? Hmm…………… Seems obvious that the minimal gain in diameter from 26 to 27.5 is nearly totally masked by big travel. What’s the point?
Now on to the 29 inch wheeled 5 inch travel FS bike I rode at Interbike’s Outdoor Demo. A discernable big wheel feel here, but again, not so much in the way it ran over stuff. More so in momentum and traction. That to me is the key to a long travel full suspension bike. Momentum for carrying up and over and traction for the short steeps and corners. 650B just doesn’t get there in this respect.
So, back to a 650B full suspension versus 26″er full suspension. Obviously, unless you are into equipment disadvantages, the 26″er is by far a better choice. Heck, some big free ride rubber is already about 27.5 inches in diameter on a 26 inch rim. So again, why 650B?
It is said that 650B will get you “some of the 29″ers benefits”. That’s a nice way of saying maybe you will feel it, maybe you won’t. I’m betting you won’t, because really, how many of you have actually ridden 5 plus inch travel 29″ers? Not many. So, it is a pie in the sky statement in the first place, and likely isn’t discernable, nor even true.
It is said that a 650B long travel bike will be easier to make than a 29″er long travel FS bike. Okay, thank you Mr. Obvious. The bike I rode at Interbike was a 26″er that they slapped the 650B’s on. What does that tell you? It says to me that the difference between 650B and 26″ers is minimal. ( a 2.5″ 26″er wheel/tire is right at 27″ already) That’s exactly how it rode too. It should also be noted that long travel 29″ers can be done. (Upcoming Niner W.F.O.9) It’s just not as easy as “tweaking the drop outs and BB drop” as one product manager said about converting their long travel 26″ers to 650B FS bikes.
Do I think these Haro bikes or a full suspension 650B is a bad idea? No, I don’t. But I also think 26″ers are doing a smash up job already. I just don’t see the need for this “tweener” size. Not enough difference in performance to justify having 26 and 650B together.
That’s my take.
__________________
Part II will deal with some other issues that are said to be negatives with a long travel 29″er design
Thank you Guitar Ted!
I’ve been waiting for someone to come out and say this for a while…26in full sus. bikes are doing a great job of accomplishing the “benefits” of a 650b and really makes it pointless when you think about it. In my opinion the 650b is another way for companies to drive an already niche filled industry further into niche-ville in an effort to make profit. Its a novel idea and really I can’t blame them for trying, but unfortunately it just doesn’t seem practical. Besides companies like Lenz Sport, Niner, Ventana, and Fisher have already developed full sus. 29ers that ride as well as any 26er but with that special “big wheel” feel and with the amazing progress of 26ers in the past 5 years, the question becomes do we really need to fix a product that really isn’t broke?
I think that if we started from a clean sheet of paper 26″ wheels wouldn’t get a look in. Due to 29″ not being able to fit the whole size range of Homo Sapiens. I would think 27.5″ to be the new standard with 29″ as an option and also just for the front wheel [as offroad moto bikes].
27.5 is closer to 26″ than 29″ (1″ taller vs 1.5″ smaller). That small.
It’s a (really) small people’s frame size. 26″ has been for kids and transport bikes ever since people only grew to be ~15% shorter than we get today.
From a blank sheet, sure 650B is great for little people. 29″ for medium. For large, xl and up, we don’t have anything yet. Just for XXXL, that’s 36″.
Wheels should be proportionate to the rider, and for each riding style from a slightly different scale. For typical XC, I rate 29″ an S/M size. XS can be done, but is a bit of a stretch (stuff?)
In XC Full Suspension trim, perhaps S/M. Great Small FS 29″ers exist, and ride fine.
Commuting, 29″ could be an S. Especially now with G2 hitting mainstream (again).
My freeride 26er sports 2.5 Kendas, with an outside knob-to-knob diameter of 27″ exactly. My 4″ travel 29er sports 2.3 Rampages with an outside knob-to-knob diameter of 28.25″. From the thread on RM that inspired this post, we learned that a 650b rim with the Pacenti 2.3 tire yields a knob-to-knob diameter of 27.25″
So the real question is, is that extra quarter of an inch in diameter that you really gain from 650b worth building up a new wheel for? How is that extra quarter inch some amazing revelation that, had mountain bike designers been working with a “clean slate”, would have changed the future course of mountain biking?
The real-world numbers are much less favorable to 650b than the theoretical ones, given that the difference between 26 and 29 is only about an inch and a half, tops.
I think a tire company could make a killing with wider diameter 26er tires that yield the same outside diameter as a 650b wheel with your same old 26er rim. I can see it now- “26+, all the benefits of 650b using your existing rims!” !!! You heard it here first, folks…
Grow a set and ride a 29er. That’s all there is to it.
Good night and God Speed.
@JN: between 26″ and 29″ there’s 2.5, no more, no less. Apples and pears choose not to be compared. A 26×3.7″ is larger than a 28×1.8″. The latter with rock in deep mud, the former in deep snow.
622-559 equal 63mm equals 2.5″. Your 29″ rim should be close to 635mm on the outside. A bit surprised your Rampage is that low actually.
Swapped my 29er Hardtail for a friend’s Turner RFX (6+ inches with 36 vanilla and DHX air) this weekend and got in two longer rides.
It rolled slowly, especially on softer surfaces, even with XC-ish tires and lightweight (I-9) wheels. Climbing was slow, due to the weight, but the suspension felt efficient.
When I tried to stand, the traction wasn’t there.
And while I was able to charge down the nastiest sections of trail, I could feel the wheels dropping into bumps and holes in a way that the 29ers don’t. If a stout set of wheels could be built, a long-travel 29er would be a big improvement and the bikes could be built a little steeper for better low-speed handling without giving up much at high speed.
PS: I’m just not optimistic about 650B surviving.
Clox- I’ll measure a friend’s 26er 2.3 Nevegal just to keep things consistent for you, since that way they’d all be 2.3 trail tires with the same general tread pattern. I think it’ll give up maybe a quarter to half inch on the 2.5 Neve, making it 26.75″. That would make the difference between 26 and 29 1.5″, not 2.5″. There’s absolutely no way a 2.3 Nevegal 26er is going to measure anywhere close to 2.5″ smaller than a 29er 2.3 Rampage. No way at all.
Rim diameters don’t mean anything. What matters is actual outside effective diameter of tires. If 29er tire makers choose to make their tires smaller to save weight and appease the weight weenies, then that matters more than a theoretical outside diameter based on claimed measurements and rim diameters.
If you have actual, real measurements, and not more theory, I’d love to see the numbers.
“My freeride 26er sports 2.5 Kendas, with an outside knob-to-knob diameter of 27? exactly. My 4? travel 29er sports 2.3 Rampages with an outside knob-to-knob diameter of 28.25?. From the thread on RM that inspired this post, we learned that a 650b rim with the Pacenti 2.3 tire yields a knob-to-knob diameter of 27.25?
What if the 650b rim had a 2.5″ inch tire like the 26″ wheel? I am sure it would be noticeable bigger if both the 26″ wheel and the 650b wheel where measured.
If by “noticeable” you mean .25″, then yes.
@oliver : there’s One Whopping Inch between 26″ and 650B rim. Which-ever tire you mount, it’s going be one inch. Keep your thumb and index finger 1 inch apart (don’t cheat now!), and pull a dissatisfied face. See?
Now do it with 2.5 inches, and see what a difference that makes. How much would you pay for 1″, and how much for 2.5″? And what if 2.5″ became the same price as 26″, and 650B was more boutique, with fewer parts choices?
I have to say the title of this entry is kinda off the mark – I’d say this isn’t post explaining why a long travel 29er makes sense (no case is really being made for 29ers). It is more a commentary and criticism of the 650b wheelsize when I read it.
Why not let things just play out here right? New tires are on the way from Kenda right?
How about fitting a 26er with Nevegal 2.3s and then fitting a similary spec’d 650b fs frame with the same amount of travel – say two trail bikes – and seeing how they fair against each other. Hell if you want to throw a long chainstayed 29er FS bike into the mix – let’s do it.
Someone chatting with me made a good observation. We have hardtails, softails, 3″ XC FS bikes, 5″ travel “all mountain” bikes, 7″ travel freeride bikes, 8 and 9″ travel DH bikes – so why can’t we handle another wheelsize option into the mix and see what plays out? When I heard that it made a lot of sense to me.
I know for a guy like me – it is highly doubtful that someone is going to be able to build a 29er long travel FS bike that will be comfortable for me at my height at 5’9″ tall. If the 650b gives some benefits over a 26er for me as a rider – that’ll be a cool thing in my book.
Cheers,
Mark
MMcG: Respectfully, the “solution” given for 29″er long travel bikes has been given as 650B. I’m sure you are aware that this is one of the things the 650B advocates have been putting out there, right?
So, it is necessary then to dispel that as a better solution than actually building a 29″er long travel full suspension bike. In a way, yes, I am writing off 650B FS as a viable platform, but only because it really doesn’t do anything better than what a 26″er FS or a 29″er FS does.
As I stated, there is no discernable “big wheel” benefits in 650B long travel. The suspension masks any minute gains made by having a slightly larger wheel than a 26″er. Remember, we are discussing five plus inches of travel here, not a XC platform, or hardtails where 650B makes more sense to me.
To say that we have all of these sub-categories of bikes, (true that) and then to say that this justifies another wheelsize is a big stretch in my mind. Really, that has got nothing to do with the discussion of wheel diameter here. It didn’t with 29″ers, and it doesn’t with 650B either.
The end rtesult is that to develope a fork and punch out a bunch of tires for 650B long travel isn’t really necessary. 26″er free ride/ all mountain has us covered for those that want a bike that fits and handles severe trails, like those of the East Coast.
650B won’t yeild a discernable big wheeled benefit, so I say, “Why bother?”
Amen! I’m stoked, because I’ve been buried in riding and work for a few days now, and I just came up for air and read this thread. I guess I wasn’t too surprised when Guitar Ted and I were on the same page (we frequently are), but I’m stoked to see you all are as well.
First, the whole 650b thing for me is a big waste of time. Being 100-percent sold on 29-inch/700c mountain bike wheels, I’ve moved beyond 650b. ‘Nuff said.
And second, from the moment I built my first Dos Niner and began this big 29er experiment, I’ve waited for the moment that I was able to build my very own long travel 29 inch mountain bike, because all of the virtues a 29er has in “normal” mountain bike terrain are going to be magnified when you get the bike into truly heinous “big bike” terrain, like big drops, huge rocks, fast downhills and gnarly off-cambers. In each one of those conditions, the benefits of the flatter trajectory of a big wheel are going to be an even bigger advantage relative to your peers on kiddie wheeled bikes, or even 650b “tweeners.”
I wanna’ rock out with big wheels on every bike, in every terrain! Let’s go BIG!
OK, maybe not “all”, but “most” of us are on the same page… I know not everyone rides 29 all the time. Don’t mean to be insensitive with my “kiddie wheel” jokes. Sorry…
I don’t understand why there would be any fewer headaches involved in designing a 650b long travel bike compared to a 29er long travel bike.
The top reason riders choose 29er bikes is not one of smoother rolling or a lower angle of attack, it’s because they fit tall riders better. It seems that the typical 29er customer is over 5’10″ (often over 6′) for a good reason. The tall rider has a higher centre of gravity. The longer wheelbase and higher wheel centre of rotation enhances the tall rider’s stability. The b.b. height is no different to a that of a 26er. That the larger wheel has some enhanced rolling characteristics is a nice bonus.
It makes sense that a 650b-wheel bike would accomplish the same for a different segment of riders. However, the bike MUST be engineered around the wheel size. Simply stuffing larger wheels in a 26er frame will only raise the b.b. height and the rider’s c.o.g. yielding no improvement over the stability that rider would feel on a 26er. We’re fooling ourselves to believe that 650b long travel is in any way cheaper or easier to do than than 29er long travel.
If 650b wheels are stuffed into 26er frames, then tire size would be restricted to about 2.1″. On long travel bikes, the whole point is to be able to attack more gnarly terrain with more confidence. 2.1″ tires are not the right tool for this job. In order for a 650b to be worthwhile with long travel suspension, the frame must accomodate 2.5″ tires with plenty of frame and fork clearance. This would necessitate a distinct frame designed for 650b wheels thereby making it NOT a quick fix.
So then, is the increment between 26″ and 650b significant enough to make a detectable difference in fit or in bump-eating ability? If it is, then everything else is a matter of economics. Offering things in more sizes increases the manufacturers costs. If Giro Helmets made only one model of helmet in one size, all they would have to do is make enough helmets to to fit all the heads out there. And it would be cheap to make helmets. But, introduce three sizes, and Giro must guesstimate how many of each to make, they need to buy three sets of molds instead of one, they must hold a larger inventory which means it takes longer to convert cost of manufacturing into revenue, they’ll have to sell off unsold inventory at the end of the year at virtually no profit. All these factors of offering three helmet sizes make helmets cost more money and the only place that money comes from is the end-customer’s wallet.
If Haro can convince customers that they need a 650b bike, Haro needs to take the risk of providing them. Since a new product will only be accepted by the market if it either performs better or is just as good but cheaper, Haro will certainly loose money on this venture for quite a few years before the cost of manufacturing can be diluted over a large enough market. But the only way they’ll be able to accomplish this is if the product actually works and does something that a 26″ long travel bike cannot.
GT – Aside from riding the Lunchbox (to me the only long travel 29er to make any sense at all due to the short chainstays it incorporates) and the one prototype 650b bike – what other bikes have you ridden to come to your personal conclusion?
If you are making the argument that for plus 5″ travel full suspension bikes that 650b doesn’t make sense, I would have to make an additional argument that for the majority of riders that a plus 5″ travel 29er makes even less sense. Note I state for the majority of riders.
There may be situations, such as Alex Morgan’s personal 29er DH bike(s) where specific design elements make the long travel 29ers work. I’ll agree to that for sure. Well maybe for some areas of the country where super long chain stays are okay – maybe yeah.
But for real technical, rocky, gnarly, terrain – having a bike with 18.2″ and up chainstays (to prevent the 29er wheel from potentially hitting the seat tube etc. etc) just doesn’t make a ton of sense to me. Again, my viewpoint – others will differ.
We should also be sure to compare the 650b wheel/tire combos to matching 26″ wheel/tire combos as we move forward.
Maybe what we need to do is get a Marin FS bike and equip it first with 26″ wheels with Nevegal 2.3s and when they become available – equip that same frame (the 650bs will fit the frame) with some 650b hoops with 650b 2.3 Nevegals and see what the results are.
That’d be a cool “test” to run to provide real trail time analysis of whether or not 650b can help or not.
Think Marin would be interested in such a test?
Heck – maybe we can get Haro to provide a bike and assemble a group of test pilots and have at it. hrmmmm.
Don’t you people have jobs? Like real ones? Jeeez.
No I’m “resting” at present, possibly for two whole months…….
@MMcG
“But for real technical, rocky, gnarly, terrain – having a bike with 18.2? and up chainstays (to prevent the 29er wheel from potentially hitting the seat tube etc. etc) just doesn’t make a ton of sense to me. Again, my viewpoint – others will differ.”
Don;t be close-minded but open-minded who said that a suspension design must compress towards the SEAT TUBE?
Why not creating a sus. deisgn where the wheel goes up and rearwards? How about that? In such a situation you just keep the short stays 17″ or just a bit more.
Do y’all realize, that if wheels and tires could easily be custom made for series production, wheels would come in almost the same increments as the frames?
Think about it. If a frame goes up a 2″ size increment, the perfect rider will have a 2″ longer inseam, and ~4″ taller total height. Wheels (~80% of inseam) would go up more than 1.5″ as well.
XS-26″
S-27.5″
M-29″
L-30.5″
XL-32″
Going from 26.5″ to 27.5″ warrants a rider height increase of less than a typical frame size!!!
Know any 14″/XS frame rider who want 24″ for XC? I know few. They want 26″.
16″/S sized bikes with 27.5″ wheels? Totally normal!
18″/M with 29″, sure!
20″/L with 30.5″, peepz want that already, and wouldn’t see the difference over 29″
22″/XL with 32″, peepz want that too.
See?
David Copperfield- I was just discussing this with somene today.
Something like a Canfield “One” fs design would work for that type of scenario I think.
Google Canfield Brothers for more information. Even in 26″ wheel configuration those frames feature 17.5″ chainstays though.
I was thinking of a 5 or 6″ travel bike with 17″ or thereabouts stays – since that’s what I used to ride primarily when I owned a Balfa Belair and carried a Balfa 2step demo bike while I served as a Part Time Sales rep for Balfa Cycles out of Quebec.
So yeah – a rearward and upward axle path might work out well. Good point.
Mark
The “rearward and upward” axle path already exists in the multitude of multi-link, active, virtual pivot designs. Intense/Santa Cruz VPP does this, as does Niner’s CVA, Ellsworth ICT, Specialized’s Horst Link, Maverick etc. There’s a limit, however, to the degree of rearward motion they can have because the rearward component is too great, the suspension will tug really hard on the chain and chain tension will prevent the suspension from being active. Because of this, there’s usually more upwrard than rearward component to the axle path and at some point before the end of travel, it it starts moving back towards the bike. Maverick’s suspension design comes very close to parallelling the front axle’s path because the b.b. moves with the swingarm to a great extent, minimizing chain growth. The downside? A b.b. that changes position relative to the saddle position.
Outland’s original VPP was good at this but way ahead of its time.
when i ride rigid, 29er is great.
when i ride a big susser, im doing huge drops and whatnot. the 29ers dont take it. theres no point unless you ride a big bike like a complete sally.
29er dont feel right on 30+ jumps and 10+ drops. so why make a bike for it? thats what a long travel bike does people. again unless you ride a big bike like a sally.
if your on a 29er,make it rigid,as God intended.
Walt from Walt Works has a 29er DH bike. 7″ of travel, I believe. He raced it last season and nothing blew up on it.
I don’t think, with properly built wheels, that wheel strength is as big of an issue as people think. Walt didn’t break any wheels, and I know a couple DH kids that tear up 26″ wheels.
UK. “resting”? That sounds like no job to me. GET OUTSIDE AND CUT THE DAMN GRASS OR SOMETHING!! Shoot…
UK. “resting”? That sounds like no job to me. GET OUTSIDE AND CUT THE DAMN GRASS OR SOMETHING!! Shoot…
I don’t now if this has been said because frankly, half of those posts are too long to read. Bullet points people. Anyway, here is my suggestion in bullet point form:
-long travel 69er
Done. Next.
nice. concise and to the f’n point. me likey.
Really, most of this discussion is semantics. The expression “just shut up and go ride” comes to mind and IMO there is not much of a way to go wrong.
That said, as far as my opinion on it, I am pretty much sold on 29er for a plethora of reasons but I have carefully evaluated the geometry of all of the 29er full suspensions I feel like every single one is a compromise in one way or another. This is from the best tried and true 26″ geometry, and this is why 98% of 29ers still retain heavy XC geometry. I think the longer stays of 29ers in full suspension still work great because of the increased contact patch, especially bikes with low seat post angles and for taller people positioned father back with long seat posts, but the correct central position for that rear tire should still be an inch farther forward than these 29ers with 18″ and longer rear stays. This is why they “climb so great,” — but those long stays are long stays and to me at least, it makes these bikes feel really big and is great in sweeping corners but can be hard to deal with in tight technical terrain. I think. The bike makers I’ve spoken with, at the end of the day, also seem a little uncomfortable with the long stays they are putting out in full suspension 29ers; it sounds to me like market demand is driving it rather than their personal beliefs as bike makers. The combo of these longer stays, with say a more AM-like geometry like a 69d head tube, would be super stable but the wheelbase is a good 2″ more than most riders’ existing bikes and are harder to maneuver in tight situations. That said, I think a 4″ or larger 29er in full suspension is probably just killer. I was personally about two seconds away from ordering one myself.
When I started seeing the geometry numbers of some of the new 650b bikes coming out, it pretty much sealed the deal for me on believing in the wheel size. I still think 29er is where it is at. But 650b is coming along and the tire selection out now and shortly is now good enough for me personally to be sold on it. Most importantly, 650b lets you retain tried-and-true 26er geom. with some of the advantages of a larger tire, even it if is just slightly larger. Really also, how many of us regularly ride 2.5 tires?
I do consider 650b to be a “compromise” from what I really want, a short stayed super aggressive big wheeled trail bike, but 650b offers the best options for me while keeping that magical 4″ and 5″ geometry while still letting me burp a little more out of the tires than teeny 26″ wheels. The bike stays fun and super maneuverable and you can even rake the bike out and continue to have reasonable wheelbase. They also seem to rip around corners and feel a little more “playful” than some 29″ wheeled bikes I’ve ridden (that feel like trucks) and the wheel itself generates a more enthusiastic feeling than some 29ers that need mach-nine to feel as fun as the same trail on 26″ for example.
So I am not 100% sold on 650b. I still have and will probably keep bikes in all three categories (though I am phasing out 26″). But I think 650b has a lot to it…
So for me, especially with hardtails, 29er rules, but in full suspension my vote is stay 26″ or try 650b, that is my plan…