The days of one wheel size fits all and one size to conquer all terrain are gone. No longer do we have brands touting that 27.5 is the wheel size to end all debate and the only size to throw on your bike. We now know that 29er is faster, 27.5 more nimble and 26 inch is pretty much reserved for the pump track, slopestyle course and anyone feeling a little nostalgic. We decided to conduct an experiment and build up a mullet bike to see how it goes in all types of terrain, we grabbed a Commencal Meta AM 29 frame and got busy…..
By Mike Branch
The time comes when all of us really need to scratch the itch and get a new bike to hit the trails with and with the lack of bikes available with COVID-19, we thought it best to get building. If I was building up my own bike then I had plenty of room to experiment, so why not give a mullet bike a try and make this thing super burly.
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The Frame
First and foremost it was time to decide what frame to go for and I was pretty sold on a Commencal Meta AM 29, but the question was which year to choose. The 2020 frames were still in stock but the 2021 frames had just hit the shelves at Commencal Australia and a tough decision was ahead. The main differences in the two frame designs is the bike got a slacker head angle at 63.5 and a steeper seat angle at 78 degress, sounds good right?
The issue would be when we went to mullet the bike and whacked a 27.5 wheel in the rear. This would slacken the head angle at least another 1.5 degrees, bringing it down to around 62 degrees head angle or less, making it a little too reminiscent of Pinkbike’s grim donut. So the decision was made to go with the 2020 frame and get building…
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The Build
Once the frame was chosen it was time to get some components on the bike and shop for suspension. The Fork we wanted was a Rockshox Zeb and there were none available in Australia, we managed to snaffle one from the UK and had it shipped, the only issue is that it was a 190mm ZEB, but if the travel was too much we could easily change the air spring and drop the travel down. The rear suspension was taken care of by a Rockshox Super Deluxe Ultimate with two tokens fitted, air suspension chosen for this build despite the hunger for coil we have had in the past.
The rest of the build came together as a matter of want, need and availability. Sacrifices were made on some parts purely because of availability given the current situation in the bike industry. The stoppers were Shimano Deore 4 pot brakes, a full SRAM GX Eagle drivetrain with absolute black oval chain ring, Commencal’s in house brand ‘Ride Alpha’ took care of the bars and stem, sensus grips were fitted, a 190mm dropper by Kind Shock and last but not least, she rolled on a set of Hope Fortus 29er Wheels with Pro 4 hubs.
To get the mullet mode experiment rolling we grabbed a set of E13 Enduro wheels in 27.5, with the view to upgrade to a 27.5 Hope Fortus if it all worked out.
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On the Trail 297 Mullet mode
So now that she was all built up it was time to hit the trails and see how the bike went in mullet mode. The bonus of choosing the 2020 Meta frame was that the bottom bracket was a touch higher than the 2021 frame, that combined with the 190mm fork meant that there were no pedal strikes despite the 27.5 wheel lowering the bottom bracket. The first spot the bike was tested was the Hennessey Hill DH track at Beerburrum, a black diamond trail with enough features, flow and jumps to get the testing well and truly under way.
The first thing that was noticed in mullet mode was exactly how responsive the bike was, it almost felt as snappy as a 27.5 bike. It felt super responsive and seemed to really carve into corners and not want to stand up at all, something a 29er can sometimes want to do. Honestly the bike felt great, but when it came time to ride back up to the top, that’s when things got a little interesting. The super slack head angle due to the mullet mode and the longer fork led to a super slack seat angle and as a result the bike climbed like a 2014 Giant reign….. well maybe not that bad, but still.
Even after changing the fork travel back down to 170mm, the seat angle was still super slack in mullet mode and this led to a pretty poor climbing bike. Multiple different locations were used to test and overall a resounding theme rang true, the seat angle became too slack and as a result the bike climbed very poorly. Once the 29er wheel was whacked back in the rear, the bike climbed extremely well for a long travel enduro bike and it was clear that the mullet bike would not climb anywhere near as well.
On the Trail 29er
Once converted back to a full 29er the Commencal Meta AM 29 became a great all-round bike, it felt great on the trail, was planted and I really started to feel at home on the bike. The bike climbs well for a long travel bike, descends great, handles the jank and performs really well. The characteristics of the Meta are similar to many of the Commencal Bikes I have ridden in the past, fun, capable and at home when things get a little rowdy. For a 29er it certainly felt comfortable in the air as well, something that I thought may not be the case.
The Final word
Overall the experiment went well, unfortunately we didn’t gain the results we wanted and it’s clear that whilst you can make a 29er a mullet bike…. you may well be making a bike that performs well on the downs but climbs like a pig. Would we be running the bike in mullet mode? The answer is yes in certain circumstances, that being DH runs with shuttles involved. The playfulness of the bike was a load of fun and the ability to get well and truly over the back wheel when things get steep is an added bonus, something that may lead to a wheel buzzing your butt on a 29er.
We have also changed back to a 170mm air spring in the Rockshox ZEB bringing the front end down and giving the bike a more planted feel. Overall it’s a great fork and stay tuned for a full fork review in the near future here on Brakes Wide Open.
If you are looking at building a mullet bike, keep in mind that it will change a lot of geometry on the bike and the seat angle is certainly one of them. If you want a bike that climbs well then you need a reasonably steep seat angle. As always keep the brakes wide open and we will see you on the trails….
I put a 27.5 on the rear of my 2021 Norco torrent and it’s awesome, it climbs well still but has a steeper seat tube angle and is a hardtail so that’s to be expected, also only 150 mm fork. It definitely became much more playful in the corners and on the downhill. Great experiment mate , u always have great content 👍🏻
Awesome glad you liked it! Great to hear about the hardtail, we’ve done the same with a 2021 Commencal Meta Hardtail and have found it to be quite good as well. Steeper seat angle and 150 fork aswell, although it’s hard to beat the playfulness of a 27.5 on a hardtail 👍