Alternatives on the mountain bike gear market are as rare as Californian porpoises, and no manufacturer has yet really challenged the dominance of Shimano and Sram for MTB drivetrains can shake things up. Could Sunrace be such a candidate? Since broken supply chains brought the supply of components to a standstill, at least the inexpensive cassettes from the Taiwanese company have been seen more and more frequently in the wild. Now Sunrace has expanded its range and, with the MZ 12-Speed, supplies a complete twelve-speed drivetrain for bikes, including a matching crank.
Sunrace MZ 12-Speed - at a glance
- 12-speed groupset for MTB
- Rear derailleur with switchable friction damper
- Shift lever with clamp and two-finger operating logic
- Cassette with 11-51 teeth for Shimano HG freehub
- Crank with 30 or 32 teeth, including BSA bottom bracket
- Price complete group: 484,65 Euro
Comparison with the competition from Shimano and Sram
Because the Sunrace MTB shifting group weighs 1922 grams and is on a similar level to the Shimano SLX and the Sram NX Eagle a comparison with the two entry-level groupsets is obvious. However, the crank of the Suncrace MZ 12-Speed, at 722 grams, makes a major contribution to the overall weight and is significantly heavier than the competitor models.
Like the competition, the rear derailleur has a selectable friction damper. A display on the rear of the rear derailleur cage helps with setup. Depending on the size of the last sprocket, the wrap can be adjusted quite easily.
For a better comparison with the competing MTB drivetrains from Shimano and Sram, we have researched both the prices and the weights of Shimano SLX and Sram NX Eagle. The Sunrace drivetrain with 12 gears has to compete with these two groupsets. The Shimano SLX in particular is currently available as an absolute bargain in the retrofit kit. The other drivetrains can hardly keep up. However, the compatibility with Shimano's HG freewheel speaks in favour of Sunrace and Sram.
Sunrace MZ 12-Speed - light cassette
The cassette weighs 505 grams with its 11-51 teeth and is mounted on a Shimano HG freehub, which should be of particular interest to those switching to an eleven-speed system. They can simply continue to ride the existing wheelset without having to convert to a new freehub standard. In addition to the black version we tested, there is also a silver version. Similar to Shimano, the five smallest sprockets are fitted individually to the freehub and can therefore be replaced in the event of wear.
Less ergonomic gear lever
The shifting logic on the somewhat cheap-looking lever of the Sunrace MZ 12-Speed is similar to that of Shimano gears: The chain moves up a maximum of three gears at the touch of a thumb. Down it goes by pulling with the index finger or pressing with the thumb on the lever, which is located far back and is quite narrow. Visually, the lever is somewhat reminiscent of Goofy's ears and it doesn't feel particularly ergonomic either. The small, rounded lever is extremely close to the grip clamp and is difficult to reach with the thumb, and its pressure point is also quite undefined. Sram and Shimano offer a much more ergonomic and precise shifting experience.
To change the cable, shift into the heaviest gear, as with the competition. The lever is then opened using a small plug, which should be stored carefully when screwing it in. Otherwise, the tiny part is quickly lost and the gear lever can no longer be closed.
The forged aluminium crank looks a little old-fashioned and is reminiscent of older Truvativ models. It can't keep up with the cranks from Shimano and Sram in terms of weight either. However, the SLX crank in particular scores with a weight advantage of a whopping 72 grams. What's more, the Sunrace MZ 12-Speed crank is only available with 30 or 32 teeth and only in 175 mm length.
Sunrace gearstick - in practice
Apart from a slightly delayed shifting response and a less defined shifting feel on the small levers, the chain climbs surprisingly smoothly over the sprockets, even under load. Only on the largest sprocket does the chain take a little time to shift, with the shift stop limit ending too early. However, the shifting aids on the Sunrace cassette seem to work quite reliably. Compared to Shimano, the Sunrace is missing a tooth in the heaviest gear. In practice, however, this can be overcome. The NX Eagle cassette only offers 50 teeth at the top instead of 51.
The Sunrace MZ 12-speed seems to be slightly less sensitive than other twelve-speed drivetrains when it comes to adjustment. Smooth running was quickly found in the test. The wrap indicator on the rear derailleur is also a simple but effective feature for tuning. Even after several test rides, we didn't really warm to the position and operation of the rear shift lever.
Test summary of the Sunrace MZ 12-speed MTB drivetrain
Whether the Sunrace drivetrain establishes itself as an alternative to the market leaders may also depend on the price. An upgrade kit (without cranks) for the tried-and-tested SLX is currently available for as little as 177.50 euros. The NX from Sram is available from around 247.50 euros. Unless the Sunrace MZ 12-Speed is offered with substantial discounts when it is launched, the Taiwanese drivetrain is likely to have a hard time. The gear lever in particular is a shortcoming that cannot simply be ignored. After all, it is largely responsible for the shifting performance. However, individual parts such as the lightweight cassette or the properly functioning rear derailleur could certainly make it onto one or two bikes as retrofit parts. However, the MZ 12-Speed is unlikely to be seen beyond the entry-level sector for the time being.
Stefan Frey
Editor
