Ideal for mountain bikers and trail riders on wide tyres who want more rear spray coverage than a tiny clip-on guard, without fitting a full bolt-on mudguard set.
The ZEFAL Deflector RM90+ is a rear MTB mudguard for wide tyres that suits riders who want solid spray protection without moving to a full fixed mudguard setup. The long blade, dual-material spoiler and double-orientation adjustment are all aimed at one thing: getting the guard close to the tyre so it catches more of the muck before it ends up on your back, pack or shock.
For Australian trail riding, that makes it a smart option for winter singletrack, wet fire roads and everyday transport on hardtails that don’t have rack and guard mounts. The MD-Turn seatpost mount is quick to set up on compatible posts, and the reflective ring is a handy touch if your ride home finishes in low light. At 238 g, it stays light enough for regular use while still offering the fuller rear coverage many short clip-on guards miss.
The big buying point here is fit: this model is made for wide MTB tyres up to 2.8 inches and works across 26, 27.5, 27.5+ and 29-inch wheels. If your bike runs a standard rigid seatpost and you want a cleaner, more adjustable rear guard than minimalist strap-on options, this is the practical middle ground. Just note that it is not suitable for telescopic seatposts, so it’s best matched to bikes with a fixed post or a second bike used for commuting, bikepacking or winter trail miles.
Built for wide MTB tyres
Designed around modern mountain bike sizes, with compatibility for 26, 27.5, 27.5+ and 29-inch wheels and tyres up to 2.8 inches wide.
Seatpost-mounted MD-Turn fitting
The quick screw-on mount makes setup straightforward on compatible seatposts and lets you remove or refit the guard without a complicated hardware system.
Double-orientation adjustment
You can fine-tune the guard position to sit closer to the wheel, helping improve tyre coverage and reduce spray in wet or muddy conditions.
Dual-material spoiler
The spoiler adds extra coverage while keeping some flexibility at the trailing edge, which helps the guard stay practical for rough off-road use.
Long rear profile for better coverage
With a 640 mm overall length, it offers more meaningful rear protection than very short minimalist guards that mainly protect only the saddle area.
Reflective ring for visibility
A reflective detail adds a little extra visibility in low light, which is useful for commuting or winter rides that finish after dark.
Made in France
Designed by ZEFAL’s R&D team and made in France, with a focus on durable accessory construction for regular riding use.
General
Materials & construction
Dimensions & weight
Compatibility
Features
Care
MD-Turn
We use this quick screw-on seatpost mount so you can fit the mudguard fast and dial in a secure setup on seatposts from Ø 25 to 32 mm.
Dual Material Spoiler
This spoiler is built to add extra coverage while keeping some flexibility, helping the mudguard protect better when conditions turn messy.
Double orientation
You can fine-tune the mudguard position for better tyre coverage and a closer fit to the wheel.
Visibility
A reflective ring helps you stand out better in low light and at night.
Great for
Maybe not for
Fits 26 / 27.5 / 27.5+ / 29 wheels and is recommended for tyres up to 2.8 inches. The MD-Turn mount suits seatposts from 25 to 32 mm in diameter. Not suitable for telescopic seatposts, so check your bike before ordering.
vs SKS X-BLADE
Another well-known rear MTB mudguard with wide-tyre compatibility and a seatpost-mounted design. It offers similar use-case appeal for riders wanting tool-free style coverage without full guards.
vs Crud XL Rear
A seatpost-mounted rear guard aimed at riders who want fast installation and broad compatibility on bikes without eyelets.
vs Ass Savers Win Wing MTB
A minimalist rear mudguard option for riders who prioritise low weight, quick removal and a cleaner look over broader physical coverage.
Check your seatpost before you buy
This is the big one: the mount is designed for 25 to 32 mm seatposts and it is not compatible with telescopic seatposts. If your MTB runs a dropper, this usually won’t be the right rear guard.
Best results come from careful positioning
With clip-on rear guards, coverage depends heavily on setup. Take the time to use the double-orientation adjustment so the blade sits as close to the tyre as practical without rubbing.
A strong option for hardtails and second bikes
This style makes the most sense on hardtails, commuter MTBs and utility bikes where you want good rear protection but don’t have the mounts or frame clearance for a full mudguard set.
More coverage than tiny minimalist guards
If you’ve used very short saddle-mounted guards before, this is the step up when you want more real-world back protection in rain, puddles and sloppy trail conditions.
Historic French cycling accessories brand.
ZEFAL is a French cycling accessories brand with roots dating back to 1880. The company’s history includes early links to the development of cycling hardware in France, and the ZEFAL name itself comes from a blend of Zephyr and Duralumin, tied to the launch of its lightweight pump in 1934.
Today ZEFAL is based in Jargeau, Loiret, and remains family-led. The brand produces accessories across categories including mudguards, pumps, bottle cages, luggage, lubricants and safety products, with more than 60% of its accessories manufactured in France and a strong focus on durability, testing and practical everyday use.
