"The smaller rear wheel is a little more lively and easier to turn, with lots more clearance over the back of the bike in very steep terrain."
Cotic are now offering mullet (aka MX, or mixed wheelsize) builds on their Droplink full-suspension models. The Jeht, RocketMAX and FlareMAX can now be had with 27.5in rear wheel paired to a 29in up front.
Why? Perhaps the primary reason as expressed by Cotic is for increased arse-tyre clearance on steeper terrain – especially for less tall riders. And for all sizes of riders there is the oft-stated reason of a smaller wheel being “more playful” which is what all the best mountain bikes should be about.
To offset some of the changes in geometry that occur when you install a 27.5in whele into the back end of a 29er frame, Cotic fit a 1° Works Components headset into their Mullet offerings. This puts the head angle back where it was and also slightly lifts the BB (and thus steepens the seat angle back up a bit).
Whilst the head angle is virtually the same, the reach, front centre and wheelbase all get a bit shortened. The seat angle slackens approximately 0.5° and the BB hunkers down 4-6mm. Check out the geometry tables below…
As ever with Cotic, they’ve done a fair bit of real world testing before committing to producing these builds. They even experimented with offset bushings in the rear shock (to compensate for the geometry changes) but they found that offset bushings can have a tendency to creep/rotate when set in the lengthening orientation. Cy from Cotic explains: “Offset bushings in the position to make the shock longer and lift the bike up never stay put. We used that idea to test things originally, but it simply wasn’t reliable.”
Complete bikes start from £3559 for the FlareMAX Taiwan Series due in January. Bikes with UK made frames start at £3859 for FlareMAX and £4309 for the Jeht currently.
Cotic: “As you might imagine, exact specs are somewhat fluid right now, but we have some FlareMAX UK edition and RocketMAX frames in stock, and Jeht UK edition frames in production for delivery January ’22. Taiwan FlareMAX and Jeht are due in early ’22. Hope wheels are around five weeks lead time, but the Deore drivetrains and all our suspension options are in stock. We can also supply frames with the angleset installed correctly for a DIY Mullet build, and the option works on some of our older bikes too – but email for advice on that first.”
Cotic brand ambassador Chay Granby: “I’m never going to deny that the RocketMAX is ridiculously fast at covering ground. That’s a given. Faster than the Rocket 27.5, but not as nimble. Obviously those smaller wheels are going to turn easier.
“I was in the fortunate position to have two identical bikes from 2 race seasons: one 29 and one 27.5 so I could do back to back rides and tests. The bottom line is I always found the 27.5 to be that bit more playful and fun. It’s not as quick granted.
“But that opens up a question about “why do you ride your bike to start with?” Is it to become a World Champ or is it to have fun?’