Manitou goes plus-sized at Sea Otter with new Magnum suspension fork

New Sun Ringle rims, hubs, and wheelsets for Boosted plus-sized bikes, too

Like an ever-increasing number of other bicycle companies, the Hayes Bicycle Group has embraced so-called ‘plus’ bikes in a big, big way. Yesterday at the Sea Otter Classic in Monterey, California, the Manitou division debuted its all-new, purpose-built Magnum plus–sized suspension fork family while the Sun-Ringle sub-brand unveiled the extra-wide Mulefut 50SL rims and Boost-compatible hubs.


Manitou Magnum Pro key features:

  • Dedicated 27.5+ and 29+ chassis with specific offsets and crown-to-axle lengths
  • Clearance for 3.4in-wide tyres
  • Hollow, forged aluminium crown
  • 35mm-diameter tapered 7050 aluminium stanchions
  • Cast magnesium lower legs with reverse arch and 180mm post-mount brake tabs
  • MC2+ cartridge damper with adjustable high and low-speed compression damping, adjustable bottom-out control
  • Dorado Air air spring system
  • 80/100/120/140mm (27.5in wheel) or 80/100/120mm (29in wheel) incrementally adjustable travel
  • Hexlock 110x15mm thru-axle
  • US$900 / €905
  • Immediate availability

Going big with Magnum

Rather than merely repurpose or modify an existing fork to create a new plus-sized model, Manitou says that the Magnum was purpose-built from the outset with heavier wheels and wider tyres in mind. To that end, both the 27.5+ and 29+ chassis are brand-new and wholly unique to the Manitou range with specific axle offsets (48mm for the 27.5+; 51mm for the 29+) and optimized axle-to-crown lengths that are as much as 7mm shorter than the competition’s repurposed plus forks.

Manitou claims that the new magnum will clear tires up to 3.4in-wide:

Manitou says the new Magnum was purpose-built for plus-sized bikes and not just an adaptation of an existing model

The 15mm thru-axle dropouts use the latest ‘Boost’ 110mm-wide hub spacing and there’s enough clearance beneath Manitou’s trademark reverse arch to supposedly clear a 3.4in-wide tyre. As with other Manitou forks, the wheel is secured with the company’s quick-to-operate Hexlock skewer system.

Internally, the Magnum Pro certainly has a whole lot going on.

On the spring side, the Magnum Pro borrows its Dorado Air system from Manitou’s downhill division, complete with an adjustable air chamber volume so riders can fine-tune the spring rate, and a positive/negative dual chamber system that self-equalizes for easier setup. Manitou says it’s made that initial stroke especially sensitive here, however, so that the entire tyre-plus-fork system can compress more evenly and predictably on impact. Otherwise, according to Manitou, the much lower inflation pressures typically used on plus-sized bikes would make for a uncomfortably bouncy ride since only the undamped tyre would be moving on smaller bumps.

Manitou’s method for adjusting the air chamber volume (thus affecting the spring rate) doesn’t involve adding or removing spacers. instead, you simply rearrange the ones that are snapped on to the shaft and move the seal head up and down as needed:

There are no additional spacers to add or remove on Manitou’s adjustable air volume system – simply rearrange the complete stack and move the seal head up and down as needed

Manitou says it’s even accounted for the heavier weight and increased momentum of a plus-sized wheel setup with the Dynamic Over Stroke concept. Basically, DOS provides more negative travel than usual, letting the fork extend a few extra millimeters upon top-out than usual to reduce harshness.

The other side of the fork will offer heaps of adjustability courtesy of Manitou’s Multi Control Compression System – or MC2+. Among the available tuning parameters are separate high-speed and low-speed compression damping, adjustable bottom-out control, and adjustable platform threshold – all of which can be set externally with no disassembly required.

The mc2+ damper in the manitou magnum pro features independently adjustable low-speed compression damping, high-speed compression damping, and tunable bottom-out control, all from the top of the crown:

There’s a wealth of adjustment at your fingertips

The new Magnum Pro is shipping now for aftermarket sales, and you’ll soon find both it and the OEM-only Magnum Comp model on complete bikes from Specialized, Trek, Rocky Mountain, and others.

Sun Ringle rolls out plus-sized wheels, too

To complete Hayes Bicycle Group’s so-called ‘Ride+’ component family, Sun Ringle also debuted matching rims, hubs, and wheelsets.

The new Mulefut 50SL rim is essentially a narrower version of Sun Ringle’s current Mulefut 80 fat bike hoop, complete with a similar single-walled aluminium profile but a more appropriate 44mm internal width. Also carrying over is the tubeless-friendly shape with a shallow central channel for easier inflation plus short sidewalls and raised bead humps for an extra-secure fit – an especially important attribute considering the ultra-low 10-15psi pressures used here.

Going along with the hayes bicycle group’s

The new Sun Ringle Mulefut 50SL rim

Meanwhile, big rectangular cutouts trim the claimed weight down to 618g for the 27.5 diameter and 655g for the 29er – what Sun Ringle says are the “lightest aluminium [plus] rims on the market.” Retail price is US$140 / €140.

Going along with those are new Boost-compatible Sun Ringle SRC hubs, built with cartridge bearings, a conventional three-pawl drive mechanism with 10-degree engagement speed, six-bolt rotor compatibility, and interchangeable freehub bodies for standard Shimano/SRAM or XX1-style cassettes. Sun Ringle says that even the lower-viscosity freehub body lubricant was chosen with freezing temperatures in mind.

Sun-Ringle’s new boost 148 and boost 110 hubs are ready to go :

The new SRC Boost-specific hubs from Sun-Ringle

Claimed weights are 200g and 315g for the front and rear SRC hubs, respectively, and retail prices are US$75 / €75 and US$135 / €150. Complete wheels built with Wheelsmith butted spokes and brass nipples will be available, too. Claimed weights for those are 2,220g and 2,300g per set for the 27.5in and 29in diameters, respectively. Retail price for either set is US$564 / €600.

UK and Australian prices for all of the above are still to be confirmed.


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