Ran across this picture the other day of the tire height of a 650b with a Neo2.3 which got me thinking about the tires I am running on my AllMnt rig, Minion DHF 2.5 EXO front and High Roller II in rear. So ran out to the garage and measured the height of both tires.

The DHF 2.5 (a tall 2.3 tire) measured out exactly the same as 650b with Neo 2.3, the HR2 was about 3/8th of inch shorter and think I could squeeze a DHF 2.5 on the rear of that bike.

So am I running 650b ? What is all the hype with 650b?

The tallest 26 inch tyre I have come across measures 695mm wheel dia. ( 2.4 Continental Trail King's) compared to my 650b Schwalbe 2.3 HD's which measure 705mm wheel dia. Switching the front out only (from the TK's) I have noticed better roll and grip. Since I have had no experience of the 26 inch version of the HD, I'm not sure if the benefits are from the increased dia. or the tyre pattern itself.

If the DHF 2.5 measures 705mm wheel dia. then effectively you are running 650b. However, there are some 650b tyres coming out that will measure 710mm or bigger wheel dia. You also need to factor in weight. What does the 2.5 DHF weigh? The HD comes in at 834 g.

 

My super tacky DHF 2.5 comes in at 935 and the hard compound version comes in at 835.

Have had quite a few different set of tires over the last few years on this bike (Kenda, WTB, Intense) and this is by far the best combination (roll & grip) that I have had on it so far. Don't know how much of this is the taller diameter or the tires themselves.

I just don't see the point of trying to convert an existing 26" bike to 650b when a set of taller tires appears to come close to accomplishing the same thing.

 

I almost hate to say it, but after my initial favorable reaction to 650b, I am starting to wonder if it is different enough from 26" to merit yet another standard. Not that my opinion matters, as it's already happening. I don't think I could tell the difference in a blind test, unlike 26 vs 29.

 

Thanks for your honesty. It's always refreshing when someone is willing to go against popular opinion with a sincere viewpoint.

 

What's the practical limit on sidewall height?

For reference, rim diameters are:

26: 559mm
650b: 584mm (25mm larger than 26", 38mm smaller than 29")
29: 622mm

 

Yes, the shorter sidewall of a larger wheel with the same rim width can be as stable, lighter overall, and use lower air pressure.

I measured a new 26" Ardent 2.6 wide DH tire on a downhill bike to be 1/8 inch shorter than my (relatively short) 2.3 Neo-moto 650b. Sounds like the 2.5 Minions are taller than the 2.6 Ardent, I don't know.

 

Ran across this picture the other day of the tire height of a 650b with a Neo2.3 which got me thinking about the tires I am running on my AllMnt rig, Minion DHF 2.5 EXO front and High Roller II in rear. So ran out to the garage and measured the height of both tires.

The DHF 2.5 (a tall 2.3 tire) measured out exactly the same as 650b with Neo 2.3, the HR2 was about 3/8th of inch shorter and think I could squeeze a DHF 2.5 on the rear of that bike.

So am I running 650b ? What is all the hype with 650b?

And then there's always the possibility the DHF 2.5 will come out in 650B?

 

There's very little difference in rollover from a tall 26" to a 650B tire.There is however a big difference in cornering traction and stabilty at the apex of corners in loose conditions. For that reason anyone with trails that are hard pack , without trail chunder, will struggle to notice any difference in wheel size besides acceleration, momentum and steering. All negatives for the bigger wheel sizes of similar weight tires.

I've only tried the Hd in 26" so all of the above is a direct 26" front comparison, the rear only follows. Your 650B Hd should be streets ahead of a TK2.4 in the front end cornering traction.
I still ride the MK2 2,4 on the rear of some bikes and it's only 5mm ride height lower than the TK2.4 and a rat load lighter and smoother.

 

FWIW, I just measured my 26" Maxxis Minion DHF EXO 2.5" - on an Easton Haven wheel - and it came in a hair under 26-3/4". I have no idea how the OP's tire measured a full inch taller than that.

 

Opps my bad , I measured it with the wheel on and looked like it was 27-1/2. I just took the wheel off and it measures out at 27-1/4 right down the middle knobby to knobby.

 

Note: I am a tire tester and pro-reviewer of bike components (tires, etc.), the former for one particular large brand. But I am as full of it as the next person, so take it with a grain of salt.

Although I strive to be objective as possible in all my reviews and testing, tires are somewhat personal, and how they react and work for me, and my local terrain, makes it all the more difficult. So I try to be overly picky, and dig deep into their characteristics, and look for strengths and weaknesses in any terrain and conditions. I have tested tires on my Ibis Mojo HD (26 & 650B), Mojo Classic and Moots Mooto-XZ 29er, in any sort of terrain that Colorado, Utah, AZ (a few forays in SoCal) can throw at you. My local testing terrain is predominantly loose rocky conditions, with many long steep climbs and descents, rock gardens, slick rock, an occasional smooth singletrack and lots of ugly loose gravel. In the Colorado Springs area where I ride, we have Pikes Peak gravel (pea gravel) on most of our trails, and it's one of the most nightmarish traction eaters that I have ever dealt with. Cornering, braking and climbing can be a lesson in humility.

Harsh TK's =>
In regards to the 26" TK 2.4 (Black Chili version), I never found them to offer a harsh ride, at least at 18-24psi. They are still my fave tires of all time, and I have gone through at least 7-8 pairs. Found them to offer excellent flotation and traction in loose conditions, and they are sticky on slick rock, and are conformable and pliable in rock gardens. They have one of the fattest carcasses on the market at an almost true 2.4. Specified tire size by manufacturers are pretty useless, and are only a general indication of skinny, medium and fat widths. Other fat tire have more width in regards to their knobs than the TK, but not usually the carcass.

650B vs 26 =>
There is no way that the OP measured properly. Large 26 tire measure at most a hair over 27, 26 comes in from 26.5 to 27, while any 650B is 27.5 to almost 28, comparing the same model (NN 2.35) the difference is close to an 1 inch (give or take)

gvs_nz =>
How much experience have you had riding 650B tires and wheels? What are your local conditions that you ride? I find the 650B have better rollover than 26 IMHO, though obviously not a 29er. Personally in my local conditions, I don't like the MK2 2.4's, I find they aren't as sticky on rock ramps and don't offer near the traction in loose conditions, though they do offer better acceleration, rolling, faster steering, and are lighter.

MK2 2.4 Protection
Casing width - 2.25 inches
Casing height - 2.05 inches

TK 2.4 Black Chili
Casing width - 2.38 inches
Casing height - 2.27 inches

 

MK2 2.4 Protection
Casing width - 2.25 inches
Casing height - 2.05 inches

TK 2.4 Black Chili
Casing width - 2.38 inches
Casing height - 2.27 inches

Just double checked mine as I note your MK2 is protection which are always smaller than my Racesport version.

Both Black chilli, prestretched and mounted on the same rims at the same presssure.

TK2.4 [casing and tread are same width] and are 0.5mm wider than Mk2 2.4 [ [casing and tread are same width]

TK2.4 casing and tread are both 3.9mm higher than MK2 2.4 casing and tread.[measured above the rim wall]

So they are not a bad option if someone wants a tall tire but doesn't need the extra traction and protection that goes with the extra 280g of the TK2.4. From memory the Xking 2.4 is very similar dimensions as the MK2 2.4.

 

gvs_nz =>
How much experience have you had riding 650B tires and wheels? What are your local conditions that you ride? I find the 650B have better rollover than 26 IMHO, though obviously not a 29er. Personally in my local conditions, I don't like the MK2 2.4's, I find they aren't as sticky on rock ramps and don't offer near the traction in loose conditions, though they do offer better acceleration, rolling, faster steering, and are lighter.

/QUOTE]

A couple of years. I've done back to back tests of rollover with Ra Ra 2.25's in all sizes on the same hard tail. It is noticeable to a small extent with similar volume tires but not large volume 26" tires. The extra dynamic stabilty and cornering traction by far out way any small rollover or momentum benefits. I'm pretty sure that would also sustain crtical analysis with a few engineering calculations.

I ride varied trails , mainly forrest trails, some similar to Pacific Northwest. Lots of tree roots and very few rocks. In the summer it's loose over hard pack and some trails can get pretty loose with a sandy base.Obviously polar opposite to your trails.

Once again, TK 2.4 is not harsh on the front in comparison to what? I'm comparing trail / light AM tires, not DH tires. It's harsher than the tires I prefer to ride, possibly the exception is the Big Betty. I consider a soft riding tire something like a a Race king 2.2 which is not far off in volume to the TK 2.4 but leagues apart in ride quality. Obviously not a trail tire but the comfort end of the spectrum I prefer at my light weight. I don't need heavy sidewall protection . I'm for a compromise. The TK2.2 or MK2 2.4 are that compromise as a rear tire with something like a Hd on the front.

We obviously ride in totally different conditions and the large gaps in the tread of the TK2.4 obviously hook up well for you in pea gravel etc. Quite the opposite on wet roots . The large gaps don't give much hold on wet tree roots. However they are in general a great rear tire. Just not a great front tire compared to an HD in deep loose over hard[ soil and sand not pea gravel]. In genearl they are just too heavy and harsh for general trail / AM tire when the Hd offers everything it does plus some at a lighter weight. It's obviously got to be near the top of the list if your priority is a tough as nuts tire for rocky conditions.

From memory you didn't like Hd's in particualr the wear. Ever tried pacestar Hd's. IMHO the trailstar is to soft for the small Hd tread blocks in dry and hard pack conditions anyway. Better suited to the larger blocks of the Big Betty.

Hd's are selling like hot cakes. In their wake the Tk 2.4's are in demise. Tk2.2 is still a popular tire, especially on the rear.

If i remember right you did an initial review of Neo 2.3's a few years back and rubbished both 650b rollover and neo 2.3's in general.

Times have changed?

 

Yep, slightly different terrain. I do sometimes get that locally, but it's not as common. Currently we have more snow, so I have been out on my 29er with some uber fat test tires.

I do like the HD up front, as it does hook up well and is long lasting, I just prefer a stickier fat one in the rear, so I like the TK2.4 (no 650B though). I love the Big Betty, but I destroy those in a matter of weeks in my local rocky terrain, though they're excellent for that period of time, but die too quick. I have been riding the Neo 2.3 of late since I don't have anything never, and they certainly are durable though not as fat or sticky as I like. I have them on some DL31 rims, which helps somewhat. I find they give a harsh ride since they lack volume, but they're very flickable and fast and tough.

I am waiting on some new HD's, but I wanted to try the Super Gravity version, and Schwalbe haven't sent me a pair as yet.

Thanks for the info, always nice to have a good rapport with a fellow forum rider.

 

There are too many different comparisons in this thread. If it is the same tire in both sizes then the diameter should be very noticeable with the performance differences that go hand in hand with that. But if we stick to the OP's topic the primary answer is weight. For comparison let's consider my two sets:

Neo-Motos (2.3 F, both a 2.3 and 2.1 R)
Conti Trail Kings, both at 2.4

I run the Neo-Motos for three seasons and the TKs in the winter here in New England. The TKs are black chili, not harsh to me, and grip so well that I have not tried studded tires yet. But the weight penalty is around 3/4 lbs per wheel and when spring comes the acceleration improvement is huge with the lighter tires.

I dream of a 650b tire that grips like a TK (or better) with close to the same weight and diameter of a 2.3 Neo-Moto.

Fred

 

If it is the same tire in both sizes then the diameter should be very noticeable with the performance differences that go hand in hand with that.

I have Panaracer Fire Xc Pro tires in both 26 and 27.5. In either diameter, it's a fairly stiff tire. I know the Fire Xc Pro is a dated design at this point but it's still around for a reason.

For the same trail, I come back from a ride feeling less sore on the 27.5 tires. The 27.5 version grips better on climbs, and has better traction in corners.

 

The 2.25" 650B 27.5 HD in Trail star compound. Doesn't have the paddle tread of the TK for tractoring up climbs in the snow. Should easily equal the TK on wet rocks and roots though. And you get that little extra diameter for edging over rocks and roots in climbs. That infamous 650B rollover comes in handy trudging up rocky climbs

 

Rager, might be worth checking out the 650b Vee Rubber Trail Taker's, apparently they have Pacenti marked on the side walls and appear to be the same pattern as Pacenti Mega Moto's. They weigh around 730g and measure 710mm wheel dia.

 

I have been riding a brand new 26" wheeled full suspension bike for the last few months. Upon reading some magazine articles about this 27.5/650b stuff I decided to go to the garage and measure the (outside-to- outside) diameter of my rear 26" WTB BRONSON 2.3 TCS tire. The measurement was just a few hairs over 27 inches. So I measured the the front 26" WTB WEIRWOLF 2.3 TCS tire and it came in at exactly 27". I have probably ridden a few hundred miles on these tires before this measurement was taken so I have to assume that some of the tread has worn off considering that the little whiskers have disappeared.

I read most of you describing a half inch and an inch difference between most 26 and 27.5 in tires but really that difference would be the radius not the diameter since the axle to tire dimension is the only thing that changes. I may not be that in-tune with the way my bike handles, but I can't help wonder how anyone but maybe a pro would notice a 1/4 to 1/2 difference in tire radius. Still curious about the 27.5 format though.

 

I read most of you describing a half inch and an inch difference between most 26 and 27.5 in tires but really that difference would be the radius not the diameter since the axle to tire dimension is the only thing that changes. I may not be that in-tune with the way my bike handles, but I can't help wonder how anyone but maybe a pro would notice a 1/4 to 1/2 difference in tire radius. Still curious about the 27.5 format though.

Radius = 1/2 Diameter, so it's apples to apples. The 26 and 27.5 are measurements of diameter, so that's why it's being referred to.

If a tire on a 26" rim is ~27" tall, then you have to correlate that the exact same tire on a 650B/27.5" rim is going to be around 28-28.5" tall. That's a noticeable difference any way you slice it. It might not be for everyone, but it's obviously for enough people if it's gaining popularity. Comparing different tires on different wheels on different bikes is stupid if someone wants to measure the difference in feel or performance.

Look at it in relation to the ski industry. The key measurement of a ski is the width of the waist and the amount of sidecut a ski has. There are skis of every width from 65mm all the way up to 150mm (or more), and multiple sidecuts exist for every one of those widths. I'm willing to bet that an established skier could tell the difference in performance between most of them. If mountain bikes only have three (for now) wheel sizes and they're all more than 5% different from one another, you can bet that the performance will be quantifiable and noticeable.

 

I am not a pro. However, I can DEFINITELY tell the difference between 27.5 and 26. You can't really go by numbers alone, they are not the whole story. 27.5" wheels ride noticeably different from 26" wheels, but you have to RIDE them to actually feel that difference. Measuring tires and debating on an internet forum don't really do justice to the actual ride qualities of 27.5 wheels. Find a set, go out and ride them on the same trails (for awhile), and THEN you can make some judgements about them. It's hard to make any useful decisions without some actual riding time.

 

I'd like to see an all mountain/ trail 26 inch tire in a 2.7 to 3 inch width. Kinda like the Surly Krampus 29+ but in the little wheel version. The diameter would end up being close to 27.5 but you would get that extra fat tire goodness. You could build a frame for the fatter tires that could use either 26+ fatties or regular 27.5s.