Are 29/27.5" Mullet Bikes Faster Than 29ers?

We're seeing 29/27.5" Mullet Bikes pop up all over the EWS and World Cup circuits, but is it just a fad? Or does the idea have merit? Mike Kazimer puts some timed testing in on a Rocky Mountain Instinct BC Edition to find out.
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[@UnliAhon]

Woudnt a 69er (26 rear, 29 front) would be more flickable? 😂

[@lucasvanderbilt7028]

I have a Trek 69er and it is incredibly maneuverable. It's kind of ridiculous but I love it!

[@aaronpbrooks]

Lucas VanderBilt Samesies. Mine has been collecting dust for the last year, but all of this mullet talk makes me want to do a fresh build with the frame.

[@kyleslater5245]

Similar to the 26/24 that kona tried ages ago?

[@Metal-Possum]

@@kyleslater5245 Or the 24/20 that Ibis pioneered in trials.... There is no end to this. How's about a 36er up front and a 12" in the rear.

[@dimensionsofearth]

It definitely plays into a great name. One of these days I'm going 24/26

[@nicocarrera1328]

Guys you should have tested the 27.5 bike (RM Altitude for example) with the big wheel in the front, because thats what teams who don't have an enduro 29er do, so it would be more accurate. Anyway, such a good video!!

[@m1chaelsc]

Nico Carrera yeah thats what i thought too because it kinda ruins the point using a 29er bike instead of a 27.5 frame

[@EmperorScorps18]

Should try a 27.5" frame with a 29" fork combo like how some of the pros are doing. It has a shorter chainstay than the 29" frame.

[@mattschirle]

The problem with that is it has a much larger effect on the geometry. When you go from 29" to 27.5" in the back, you lower the rear axle by ~20mm. If you go from 27.5" to 29" in the front, you raise the front axle by that same 20mm, but you also extend the axle to crown length of your fork by an additional 20mm.

[@leedove7255]

You might have issues with the front wheel hitting the downtube on full travel.

[@esdubya]

Agreed I’m thinking chuck a 29er front on a 2019 27.5 stump jumper as the bb is too low from factory and you’ll nearly get a EVO geometry and a carbon frame that would be awesome to try!

[@catg9196]

Bike magazine experimented with a 27.5 frame with a short travel and long travel fork in stock form. The long travel fork they swapped out with a 29er with the same travel as the rear. So the geo isnt much different.

[@rytisstanevicius4592]

Esdubya 0 thats what i got and going to try to put 29er fork from my friend:) just not sure how to work out offset i think 29er got 51 offset from factory, but since is mullet bike i think need to go lover . My friend got 42mm offset so I’ll try that one first to see what’s going on:))

[@karolmotala]

try to go full MX next time: 26" x 4" on the back and 29" x 2.35" on the front :D

[@ShahnewazYT]

How about a 29" front and 27.5+ on the rear? Test it on a hardtail.

[@tobiass6092]

i am building this atm. has anybody got experience due to that?

[@romand123]

I'm riding a similar set up on my 2019 GT Sensor. The only difference is that I'm running a 27.5x2.8 rear tire. It's made the bike feel more planted and maneuverable but the greatest benefit is the added climbing traction on wet days.

[@calvinjonesyoutube]

Mullet bike is perfect if you know the saying "Business in front, party in the back". I do, so it works for me.

[@dogdaysunrise1970]

I'm running 27 5F/26R on my Liteville 601 and really dig that setup

[@jmanswat2457]

I run this setup on my pivot switchblade and it's just plain fun! Best part is the experimenting with all the wheels and tire size combos with one bike. You can also switch the setup according to the terrain or trails you'll be riding; 29er for xc, 27.5 for DH and tight trails, 27.5+ for wet fall/spring riding, and mullet for inbetween. I find myself running the mullet more and more for the perception that I'm getting all the benefits of each wheel size.

[@nathoodles]

We’ve seen people win world cups on 650B, 29ers, and a mix of the two, in my opinion it really just depends on what you feel the most comfortable on, cus if you’re feeling more comfortable, you’re naturally going to go faster.

[@jameswarner8038]

wasnt you supposed to have put the 29 on the front of the 27.5 bike rather than the 27.5 on the back of the 29er?

[@bogoljubdjordjevic7528]

I can bet in my life will be same it's all bs

[@ka81alex]

@James Warner yup, the only correct way is: take a 27.5 bike, swap fork to 29 (if stock fork is 160 then new 29 fork should be 150).

[@joneugenio2017]

"exactly my thoughts" on a 27.5 = more control, agile and nimbleness

[@MybeautifulandamazingPrincess]

Using a 29 frame basically defeats the purpose of a mullet bike. A mullet bike is supposed to have a bigger wheel on the front, not a smaller wheel on the rear The frame should've been 26 or 27.5

[@TheHmheldinho]

Today I just swapped on my Altitude 27.5 2019 the fork and wheel to 29", I will try it this week.

[@KarlStilesMusic]

Working on my classic specialized stumpy m4 ht. Got some 29 forks and rim, which needs building with new hub. Cant wait to try it out 😆

[@rudySTi]

The superior Mike with a banger video. Dope.

[@AEDumit]

The mixed option gives you a slacker head angle, right? Maybe 1 degree?

[@wesleygamboa2475]

They have been doing this on the Santa Cruz Hightower Owner FB page. But they are using 29er in the front and 27.5 +(plus)in the rear, esp winter months with wet trails. They call it 297+

[@cosmicheretic8129]

I'm going to try 297+ on my switchblade.

[@ROBinJVILLE]

Im hyped up. I have a 27.5 140mm trail bike, and a 29r fork just chillin here, I'm gonna swap them.

[@JamesStoup]

No. 275 29 are all fast. But if you're slow a different bike isn't going to change shit.

[@delectablydiabolical340]

Captain obvious here.

[@3SecondsFromDeath]

This vid needs to be 27 vs 29 vs 279! The summary at the end sounded a lot like the usual 27 v 29 debate. The question remains, does mixing wheel sizes have any advantage over not mixing? I don't think there's any advantage to mixing though. Rooty sweeping tracks the 29s will be better, tight tracks the 27s will be better. If the track is a mixture, either as it will average out they will be good in one section but find other sections more difficult. Mixing is pointless, the advantage of a fast roll-over front is lost if your back wheel isn't the same. The advantage of a manoeuvrable rear is lost if the front is massive.

[@Sadokist]

Is it possible to take a 27.5 frame and throw a different fork and 29 to front? I would think that the geo change would be more significant than simply just 1.5degrees? I've got a 27.5 but want to mullet it...

[@raziasrazias7761]

Go 24" in the back and 29" on the front. Add a Super Monster T on the front (just saw the crown to put the 29"). Cant go wrong with that 👍

[@reneh.6551]

When I was a kid (1986), my dad bought me my dream bmx bike... A GT Pro Series, which I believe it had 20" wheels... However, front tire was around 2" and back tire 1.5" or 1.75"... Basically, similar principle since back then... 🚲😎

[@esdubya]

I’ve been doing this for a while now as I sent the fork off my 2016 intense tracer expert to be repaired and grabbed the fork of my 2018 Norco C1 29er and then changed the travel on the intense to 140mm to suit the 140mm fork. On my combo the chainstay actually went a little higher but the head tube angle stayed similar to original as I dropped 20mm of travel. I like the feel of the combo wheel sizes, feels natural definitely not a Frankenstein bike. In my mind as I’ve done it and been riding it for a while to me it makes more sense to put a big wheel on a 650b/27.5 bike than a small wheel on a 29er. I’m thinking chuck a 29er front on a 2019 27.5 stump jumper as the bb is too low from factory and you’ll nearly get a EVO geometry and a carbon frame that would be awesome to try!

[@brent4adv]

Most off-road motorcycles run 18" wheels in the rear and 21" wheels in the front so I'm not super surprised to see bicycle enduro riders trying this combo out.

[@mulisha0351]

19inch for motocross. (18 for woods and enduro). Idea behind it is the 18inch has a bigger and wider footprint than the 19.

[@brent4adv]

@@mulisha0351 Good call. I ran enduros and dual sports so that's what I'm familiar with. Either way, I think it's a great idea for bicycles as well.

[@BADLUX]

I'd like to know how a 26 rear and 27.5 front feels.

[@WhiteRoseAdventures]

I like my 27.5 wheels feels and rides fun on rocks, dirt, gravel any and all terrain :D

[@sdpy15]

Have a 29 and 27.5, still like the 29 for gravel and 27.5 for trail.

[@Freidenker888]

27.5 are the best aren't they? They're light, stable, the disc brakes don't get that hot and they're super agile. And the rollover behavior is more than enough!

[@AlaskaTeacherTech]

Hmmm... What comes around, goes around. My 1985 Cannondale SM500 had a 26" front + 24" rear wheel.

[@YoFabGuy]

As long as you have the power to be efficient with getting the bigger wheels moving then I don't really see the problem with a larger diameter wheel. The one trend that makes sense to me is the the 29 front and 27.5+ rear like on the e-bikes. gives you more grip, and more absorption where it really counts, while still having good roll over. Moto guys have been doing this for the last decade or so for a reason. and back to the getting big wheels rolling thing, if you put a slightly smaller chain ring on, then it should have a more similar torque curve to a 27.5 bike.

[@dannyfag1]

It must be so hard to tell when you are down to milliseconds I guess. I have run all wheel sizes and am going to try this mainly because I'm back on 650b and am getting a few pedal strikes plus don't mind a slacker head angle.... Interesting times ahead for dh this year.

[@colinwatt00]

@Pinkbike - the host explains that pros are taking a 27.5” bike and putting a 29” front wheel on to ‘get through the season’, but then he turned-around and used a 29” bike with a 27.5” wheel on the back. This is a completely different methodology and results in more significant geometry changes than adding a 29” wheel to the front rendering the whole video useless. I appreciate the effort and acknowledge it would be more labour-intensive to switch forks and front wheels than a rear wheel, but if you’re going to do something, do it right.

[@pinkbike]

The end result is similar - mixed wheel bikes, no matter how you do it, end up with a slacker head angle. The geometry that we ended up with on the Instinct is close to what you'd get when starting with a 27.5" bike. If the video made you think about bike geometry and the effect of different wheel sizes then I consider it a success. - Mike

[@colinwatt00]

Pinkbike - adding a 29” wheel to a 27.5” bike raises the BB height, reducing to a 27.5” wheel on a 29” bike lowers it. Adding a 29” wheel to a 27.5” bike maintains a short chainstay, reducing to a 27.5” wheel means a long chainstay. Adding a 29” wheel increases wheelbase, reducing to a 27.5” wheel decreases wheelbase. Adding a 29” wheel allows the end-user to mitigate geometry changes with handlebar height adjustments and headset angle-cups, reducing to a 27.5” does not. These changes -alone or combined- will have a significant effect on bike feel (which you indicated is an ‘advantage’ of mixed-wheel sizes).

[@willd0g]

Colin Watt hmmm this comment proves a strong case for me not to do this on my native 29er and adhere to the aforementioned approach of applying this to the 27.5 frames (and overforked front sus by 20mm relative to rear as per other pinbike vid)

[@marcobassot]

@@colinwatt00 thank you a lot of the explanation. I have exactly a Rocky Altitude C90 27.5 of the year 2019 and would like trying to put a 29'' wheel on the front, do you know if it's possible mantaining the 27.5 fork? How would the geometry of the bike change? Thanks a lot

[@pierss-p7110]

It's usually called 'Moto style' already. eBikes have been doing it for years, and it's becoming more or less the standard setup now because It offers precision and rollover on the front, and you can run a higher volume tire for more traction on the back for climbs. Same principle as has been the standard for years with off-road motorcycles, all MX, Enduro and rally bikes are based on the same concept. On eBikes and offroad motorcycles the overall circumference is actually quite similar when you use different volume tires to balance out the different sizes.

[@medievalman3737]

Definitely going to get a 29 inch tire for my Kobain 2.5 aggressor rear 2.6 29 assagai

[@norkisserrano]

The solution for this, is that Frame makers should build a frame with a geometry specifically for 79er (or 759) so there won’t be no compromises on both, then this will be an interesting review for this bike. I can’t wait to see and it could be my next bike.

[@trailswithtrevor1509]

I wonder how 27.5/27.5 timed out? I know, super forward thinking, but, hmmmmmm.......

[@motron1845]

I've been riding 29 up front and 650 in the back for about a year and a half. I think the differences are at the margins. Riding at 80% won't really bring out the short comings of either wheel size. 100% effort or more extreme terrain will do that.

[@no_russian8363]

Bad test. The rider should not know what he was riding. Frame should be 27.5 with 29 fork as the DH machines.

[@abadatha]

I have been thinking about doing a 29 front and 27.5x3.0 in the back on my hardtail. I think I should be able to roll over things like a 29er, stick to the ground and eat up some chatter and chunk with the 27.5+ and just generally enjoy it.

[@weichentechnikk8083]

What about those that have 27.5" native bike and want to have 29" upfront ? How would that compare i wonder.

[@jonnysnakes5417]

Would like to see this test with 3 of the same bikes but a 27.5 a 29er and a bike specifically designed as a mullet bike so the geometry is affected the way it is by putting a smaller wheel on the bike of a 29er or changing the fork n wheel on the front of a 27.5

[@stevenjalopnik1342]

Thought we wouldn’t notice the the POV footage was all on the 27.5 front and rear altitude and not the instinct bc you were using for the test. Damn

[@ImRokhound21]

Something else you should have tested was how the wheels/bike feels when you are sending it thru different jumps. The smaller circumference wheel in the back should allow you to flip the bike easier when hammering bigger drops and jumps.

[@kylelittle4988]

What about using the 27.5 chassis with a 29 fork and front wheel rather than 29 chassis and 27.5 rear wheel

[@Legend869]

Im building up an old jekyll 800 with a 27.5+ upfront and a 26 in the back. I think it'll work pretty good.

[@khalliddo1385]

nice reference with the skateboard.

[@NDemanuele1]

If I want to try putting a 27 on my 29er bike, would I need an adapter, or should it fit as is? Thanks!

[@kyleslater5245]

Depends if the hub matches. Assuming the hubs are the same it’s plug and play.

[@DmitrySokolowskiy]

Song name at the beginning of the video?

[@lizardmechanic8785]

I just tried it on a Genius Plus bike, I like it. I agree with everything he said. I call it a seven five niner, it's got a good ring to it.

[@wickedone31]

Foes Racing has had the Mixer Trail and Mixer Enduro mixed wheel bikes for years, way before the big names started to adopt it!!

[@Hawlkeye-e9p]

If you feel the back tire gets hung up more at 27.5. Thats the frame kinematics. Not the wheel size.

[@TheRiotMTB]

You still got a better time on the mullet and that means something I would think. As long as you had fun and got some enjoyment out of it that’s all that matters. What felt better is what really counts

[@midlifebiker7424]

No surprise with the results but trail looked fun so any excuse to session it is cool with me...

[@u_benhakd]

This emerges every few years and it always deems inconclusive results

[@Nondezeusproduction]

shouldnt you put a 29 front wheel on a 27.5 bike the have a benefits of the geometry of the 27.5 bike ?

[@pinkbike]

It’s a lot easier to swap a rear wheel between laps than a fork. This made it possible to get the timed runs done more efficiently. The geometry of the mixed wheel bike is still similar to what you’d get by putting a big wheel on a 27.5” bike. Every scenario is going to be different regarding geometry - in this case we went with what was the simplest way to compare the effect of a wheel size change.

[@timc7312]

@@pinkbikeuse 2 bikes , you don't get the benefit of short chain stays with 29"frame ,if bottom bracket is to high experiment with angle headset

[@willd0g]

tim c my 29er chain stay length is 432mm from memory - what’s typical for 27.5 frames?

[@delectablydiabolical340]

Smaller tire in the back is optimal, but bike manufacturers have to pretend like it's actual technological advancement, and trickle it out slowly. That way they make money by selling the latest and greatest. It has been the standard on dirt bikes for decades, for damn good reason. After everyone buys their new reverse mullet with 27.5 in the back, they'll make bikes with 26" in the back and everyone will buy that.

[@finnsteele8305]

was waiting for this video

[@SeatTimeClips]

I just want to ride that trail, I don't care what size wheels I'm on.

[@E.T_rode_bikes_As_well]

Trek allready did a 69er 29 front and 26 rear like 10-15 years ago. 😂

[@lordmarshall5239]

Back after the 90s, the DH scene had a time people ran 26/24. That’s kind of early 3.0 tire days and the slack head angle was attractive for the explosion of the terrain and riding evolution. I think other comments here are making some points. The right frame geometry designed for this could really show the difference over either straight up wheel design or hybrid mutt hack

[@johanneshockerup3017]

Man, this trail looks sick :P

[@James-hh1lq]

What looks unwell .

[@leonardomalmeida9709]

Well, maybe we dont have a perfect geometry for this mix fo size tyres. Hope they keep trying!

[@dirtrocksandtrees]

Adam Fernandez MIke, I think you missed the point. You’ve got about 17mm more ass clearance with that 27.5 rear. You are capable of more WRT getting back and down that you are likely to use at 80%.. And the other item is clearance on the other side when hopping / gapping humps and whatnot... the small tire will clear stuff sooner.. Again this is kinda race-pace stuff... Or maybe... the point is really that 29ers are rad and a smaller rear is kinda not important Anywhoooo...

[@janvincentjamolod5078]

Wanna try 26er rear 27.5 front since im riding a knolly podium with a 27.5 compatible fork...

[@kyleslater5245]

I haven’t noticed the difference yet tbh. But I used a plus tire to reach 27.5 diameter and am still using a 26” rim. GT dhi race switched some 02 dorados for a 15 rc domain 27.5. Only impression so far is 200mm up frost works better with the 225 rear then 180 up front.

[@janvincentjamolod5078]

@@kyleslater5245 i see.. like youre tryin to say in order to have the same slack with different sized tires... i havent tried it yet.. but riding 27.5 bike i just notice that im pretty much confident on my front end not throwing around high speed at loose rocks much stable.. unlike the 26er front.., ive been riding 26er a long time.. small wheels are fun but bigger wheels are just good for those rocks.. just like what the video tryin to say...

[@kyleslater5245]

Fair point. My terrain doesn’t really include rocks

[@janvincentjamolod5078]

@@kyleslater5245 nevertheless thank you for your opinion and experience..

[@shadowprice8100]

hmm you started with 29er and put 27.5 on rear... I think starting with 27.5 and putting 29er on front is better, because the rear suspension and frame is designed to work with the 27.5, so if you change the fork to 29er , rear should work better... I know its not practical to change the fork and wheel for testing but , Martin Maes uses the mullet combo on his gt force (27.5) and is dominating the ews... so it may just be more than just running the mullet combo on any bike, you may have to tune the entire bike to suit.

[@jackmiller1324]

26" aint dead.... i cant afford new DH bikes to keep up.

[@gustavbergstrom1502]

Can you confirm what size tyres you used? Front and rear! Wider 27,5 in The back?if its in The video om sorry :)

[@pinkbike]

2.5" up front, and 2.4" in the back.

[@gustavbergstrom1502]

@@pinkbike thank you! What made you go for a smaller 27,5 Tyre? Is this how this black vodoo magic set up is The "way to go" with The 2.5 29" and 2.4 27"? What makes this set up better/worse then if you would run a 2.8 or 3.0 27" Tyre in The rear? Im really intressted in your thoughts about The set up When going 29 front 27 rear. Wich Tyre sizes ran Martin maes When he won The EWS?

[@johncast9565]

at 2:15 you wrote the words / on the top right corner on the opposite sides.

[@vcval]

I'm back curiosity got to me .... lol staggered wheels size, big front small back = oddball , small front large rear = modball .... one of my customs has 20inch front 8 inch rear my son loves it

[@yamahschector]

What climbs better? Do I sacrifice the climb for the playfulness of the mullet

[@Vate13]

26 front and 26 rear.

[@CalaveraChronicles]

I wonder if it makes a difference in climbing.

[@thepebblesexplore83]

Is the music that kicks in at like 3:05 a clown nose that’s been edited and filtered?

[@masonrudolph7249]

me left leg i run 29. and my right leg i run 28.9

[@KieronymousBoof]

You should think about 172.5 / 167.5 cranks.

[@area4race]

Liteville is doing this for ages and calls it scaled sizing

[@Fr3dTHC83]

I've got the spectral-on, its 29 er front and 27.5+ rear, it's feel amazing to ride

[@ankolsiopon8359]

What if Front 27.5, rear 29?

[@dillydean]

Of course it's not drastically different 😄 it's all down to feel! If it feels faster it will ride faster for you!

[@TheDavidjakeson]

You shoulda thrown in a few laps with a 27.5 front/29 rear just for the lolz.

[@leoelkins3664]

I'm afraid my 26/27.5 santacruz nomad carbon 2012 is the fastest bike in the world. @leo_elkins

[@obc3095]

1/2 26" ain't dead. my 2011 Giant faith mixer kills it.

[@tomhammond2259]

Has no one heard of the Foes Racing Mixer?

[@TheNationalTrails]

Era of Flip Chips and tire clearance.

[@vasipro]

27.5+ front makes sense because some great forks from FOX are way cheaper second hand instead of new 2000 USD 29 forks and 27.5+ still paired with a good fork are verry capable. No loss there in my books.

[@cgsrtkzsytriul]

I want the smaller rear wheel to bunnyhop, manny, and flick better. Also, dirt bikes have used smaller rear wheels since the 80s.

[@lloydm5562]

Heard about new wheel size marketed as The Final Solution? 28.25..

[@sergiomorales1253]

What about climing with that size?

[@Surfratglass]

Here in Colorado it’s called the 9,7 ooooohhh

[@razorree]

more tries ! more runs ! and also 27.5" ! :)

[@luca6478]

what about 26" did it just die?

[@laurimakinen4872]

Modern Farthing = 97,5er = Frankenbike = Mullet = Mutt I would Love to try this with my Giant Reign! 29" on the front might just be awesome!

[@arbeemtb6648]

I think you're looking at the results incorrectly here. With the sample size you took you were on average 1.4 seconds faster on the mixed wheelset. That's all you can take away from these results. Because there are so many variables at play and because you don't know which set of variables would effect a given run you simply can't take them into account. Your sample size equates to you being roughly 1.4% faster on the mixed wheel size. Given a larger sample size the results would probably change a little, but imagine being 1.4% faster over a much longer run and this setup starts to make more sense, especially so in a race environment where every millisecond counts. Either the people racing this setup are faster, or they're more comfortable without taking a hit to their times. Eitherway, this setup is a huge plus for those that can make it work.

[@Hawlkeye-e9p]

Piss poor test without a frame with a flip chip. Maybe test with offset bushings?

[@AltitudeAerials]

Inconclusive need to redo with a native 27.5 frame and slap on a 29r fork n tire on it and compare times

[@weichentechnikk8083]

totally agree

[@ZOB4]

I'll keep my 27.5 (front and back) trail bike, thanks.

[@Freidenker888]

27.5 is the golden middle and in my opinion the best! It's light, stable, agile and a better rollover behavior than 26 inches! Isn't it so?

[@arnoperret7364]

Who spoted the rabbit at 6:32 ?

[@Freidenker888]

Put on 27.5 front and back and you'll see for a normal all mountain - trail rider they're the best! They're light, stable, the disc brakes don't get that hot and they're super agile and playful. And the rollover behavior is more than enough!

[@juancarlosgarciazambrano7306]

A mixer?

[@Surfratglass]

This test would be better served with a purpose built mullet bike!

[@RCKING1]

should redo this test with geometron g1 to keep same geo

[@WattWireNet]

Is it just me, or should he have spent the first 3rd of the video standing behind the bike he was talking about instead of a traditional 29"/29" setup?

[@brandonhughes882]

This is nothing new in the bicycle industry, but the idea just keeps getting scaled up. DH bikes had 26” wheels and at the same time it was popular to see freeride bikes with 24.” Then some bikes came from the factory with mixed wheel sets like the early Specialized Big Hit (24” rear/26” front) and later on the Trek 69er (26” rear/29” front). In the motorcycle world they’ve been using mixed wheel sizes from eons ago up to the present. For DH/Enduro I think a frame specifically designed for using only 27.5” rear/29” front could really be the way to go. I don’t see the XC world benefiting from mixed wheel sizes though.

[@dryland5742]

mix works great for heavier riders

[@jonanolakers1567]

I think intenses "279" sounds good