So I’ve done a short mullet experiment.

I traded the 29er rear wheel on my chameleon hard tail for the 27.5 wheel from my other bike. Tires are 2.5 SE5 on the small wheel and 2.5 SE6 on the big wheel. Both rims 30mm inner. Same cornering knobs. The smaller wheel does lower the back end by about 2 cm so the head and seat tube angle slacken a touch. I rode a short loop of about 20 minutes with some easy rolling to start, a short climb and intermediate flow type trail with lots of corners and small jumps. I tried to concentrate on cornering and rolling speed. If there’s a difference it’s pretty subtle to me. Based on this pretty limited test, I wouldn’t base a bike purchase on whether or not a bike is a mullet or not. I can see a mullet for extra butt clearance as I do scrub occasionally with any bike. My legs are 31 inseam in bare feet. But that’s not a big deal for me.

I tried this earlier in the season but one wheel had an old cassette which started skipping with the new chain on the Chameleon, so I couldn’t complete the trial properly. 

Has anyone else done a similar experiment and if so, what did you think?

I have run 27.5" bikes with 29" fronts and 29" bikes with 27.5" rears. The difference in handling between 29 and mullet is not as much as 27.5 and mullet. The 29 front wheel really dictates a lot of the feel of the bike. That said, the mullets definitely do carve corners better than 29. I don't think I would notice as much on flow trails as on flat corners where you really dig in and carve the bike. I also notice a difference with bunny hops, and bike in air stuff where the smaller wheels make a bigger difference. I don't need clearance at 6'2" but I prefer mullet over 29 for the most part.

I been riding the same set of nice juicy machine made berms on a 29/29 and now on a 29/27

one of the switch back features is a series of 10 linked turns

i duno if its the wheels or the Geo but IMO the mullet just carves better

a local rider has an SC 26/ 29 mullet and it is visibly wierd

Was resisting mullets for a while but now both my HT and FS are setup that way. Acceleration, cornering (more noticeable on HT) and jumping feel better that way. 

Both frames are 29"

Tempted to try it on my Trance-X.  With the flip chip, I could go in steep HA mode and let a 27.5 rear wheel slack it out.  

Have not been motivated enough to put in the effort of explaining to the wife why I stole her wheel…

Posted by: heckler

Have not been motivated enough to put in the effort of explaining to the wife why I stole her wheel…

That's hilarious 😂 

When you look at the turning radius of a mullet around a corner, the rear wheel tracks inside the 29 front. Not sure exactly how that translates but maybe snappier out of corners once the front wheel has fin8shed the turn?

Posted by: RAHrider

When you look at the turning radius of a mullet around a corner, the rear wheel tracks inside the 29 front. Not sure exactly how that translates but maybe snappier out of corners once the front wheel has fin8shed the turn?

I've never gone Moo-Leet, but I am trying to understand why the rear wheel would track differently on a 29 x 2 vs. 29/27? In the same frame the wheel's contact patch would be in the same spot so why would the back end of the bike take a different line? Not saying it doesn't I just can't compute the reason.

Posted by: Vikb

Posted by: RAHrider

When you look at the turning radius of a mullet around a corner, the rear wheel tracks inside the 29 front. Not sure exactly how that translates but maybe snappier out of corners once the front wheel has fin8shed the turn?

I've never gone Moo-Leet, but I am trying to understand why the rear wheel would track differently on a 29 x 2 vs. 29/27? In the same frame the wheel's contact patch would be in the same spot so why would the back end of the bike take a different line? Not saying it doesn't I just can't compute the reason.

Same boat. I think if a mullet allows a shorter rear centre then you will have a bike that will corner quicker because of the shorter wheelbase. But how much is that difference? Someone above said front end geometry of a bike has far more impact on a bike's handling characteristics than any other single thing and I think that’s probably true.

Posted by: Vikb

Posted by: RAHrider

When you look at the turning radius of a mullet around a corner, the rear wheel tracks inside the 29 front. Not sure exactly how that translates but maybe snappier out of corners once the front wheel has fin8shed the turn?

I've never gone Moo-Leet, but I am trying to understand why the rear wheel would track differently on a 29 x 2 vs. 29/27? In the same frame the wheel's contact patch would be in the same spot so why would the back end of the bike take a different line? Not saying it doesn't I just can't compute the reason.

Smaller rear wheel will cut a tighter arc through the turn than a bigger rear wheel, as illustrated/explained here:

https://bikerumor.com/review-has-mullet-cycles-nailed-mixing-wheel-sizes-with-their-titanium-honey-maker/

Posted by: andy-eunson

Same boat. I think if a mullet allows a shorter rear centre then you will have a bike that will corner quicker because of the shorter wheelbase. But how much is that difference? Someone above said front end geometry of a bike has far more impact on a bike's handling characteristics than any other single thing and I think that’s probably true.

Sure. If you have say sliding dropouts and reduce the WB with the smaller wheel I can see a notable difference in cornering and where the wheel tracks. If it's a fixed CS frame and you swap to a smaller wheel keeping the same WB I don't see how the rear wheel would track differently given the location of the tire's contact patch is the same 29er to 275er to 26er.

The turning radius of a tire when leaned over is partly dictated by the arc the tire makes on the ground.  Wheelbase length is also a contributor but not everything. If you put 27.5 wheels on a 29er, despite having the same wheelbase the smaller wheels will corner sharper due to the tighter arc the tire cuts when leaned over. The smaller rear wheel when leaned over will try to follow a tighter arc on a mullet. Think of more sidecut on a ski. If you have a powder ski, it will only carve a corner so tight as the sidecut dictates the arc of the turn to some degree.

might b a few other things going on, less  centrifugal force on a smaller wheel, less  leverage needed to to turn a  wheel with a shorter axles to ground measurement probaby some other stuff but it turns easier and i like it

kind of reminds me of my  dirt bike with the 21/18 mullet which felt way > cheap the  japanese bike with the same wheels front & rear back in the day

Posted by: mammal

Posted by: Vikb

Posted by: RAHrider

When you look at the turning radius of a mullet around a corner, the rear wheel tracks inside the 29 front. Not sure exactly how that translates but maybe snappier out of corners once the front wheel has fin8shed the turn?

I've never gone Moo-Leet, but I am trying to understand why the rear wheel would track differently on a 29 x 2 vs. 29/27? In the same frame the wheel's contact patch would be in the same spot so why would the back end of the bike take a different line? Not saying it doesn't I just can't compute the reason.

Smaller rear wheel will cut a tighter arc through the turn than a bigger rear wheel, as illustrated/explained here:

https://bikerumor.com/review-has-mullet-cycles-nailed-mixing-wheel-sizes-with-their-titanium-honey-maker/

I’ve read that three or five times and I don’t really get it. I understand a smaller wheel cuts a tighter arc. I’m not able to understand the physics of the higher axle changing things. I’m sort of getting a visual idea of it. Clearly more experiments to come. 

I appreciate all the input though because I like to understand things.

Another longer ride on some more twitchy trails and steeper black ones. Then I got home took measurements and did some math. The slope between axles is less than a degree. So I have a hard time believing the higher front axle does anything a rider would notice. Ride was good. Maybe the bike was cornering differently, a touch quicker? Big wheel back on and I’ll try to duplicate the same ride a few days.