Saris MP1 Nfinity indoor trainer platform review: Rocking and rolling

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How serious has the indoor cycling market become? In addition to the plethora of multi-thousand-dollar dedicated indoor bikes now on the market, Saris now sells an accessory for a whopping US$1,200 / £1,000 / €1,200 that serves as little more than a moving platform for your existing stationary trainer setup (Australian pricing is to be confirmed). Sounds crazy, right? No question, the MP1 Nfinity presents an exceptionally poor value argument, but it’s also surprisingly effective at bringing some of the outside indoors.

What exactly is this thing supposed to do?

The rise of indoor cycling has brought with it the inevitable group effort to make it feel more like riding outside. Virtual-reality online environments like Zwift obviously help (not to mention a giant TV), but aside from the Wahoo Fitness KICKR Climb, one key element that’s been missing from the equation is movement; your bike is rigidly locked in place in a decidedly artificial manner, and as neat as it is, all that fancy KICKR Climb thing does is raise and lower the front end of your bike in concert with your on-screen avatar.

The Saris MP1 Nfinity motion platform does a surprisingly good job of making riding indoors feel like riding outside, at least in terms of how the bike moves around beneath you.

The concept of a moving platform that replicates real-world motion on the road isn’t new; in fact, if you do a little sleuthing, you can find quite a number of homemade DIY solutions posted online. But regardless of the specific approach, the goal for these things is always the same: by re-introducing indoors the side-to-side (and fore-aft) movement you normally get while riding a bike outside, the thinking is that the whole experience feels a bit more realistic while also improving rider comfort and potentially reducing stress on your bike.

Not everyone is keen for a home project, however, and while the concept sounds simple, dialing in details such as the pivot points, spring rates, and return forces undoubtedly takes some time and effort. So to save you the hassle, Saris’s new MP1 Nfinity platform offers a ready-made solution.

The MP1 Nfinity isn’t a stationary trainer in and of itself; it’s merely a supplemental platform onto which you attach your current setup. But what it adds is a fluid fore-and-aft sliding motion, along with side-to-side tilting ability, both of which are meant to simulate how your bike actually moves beneath you on the road.

The MP1 Nfinity is big and bulky, but the deck is about as compact as it can be in order to accommodate the wide variety of stationary trainers that are currently on the market. And yes, it kind of looks like a giant saddle.

It still costs a silly amount of money, but for diehard indoor riders, it also sounds kind of intriguing, no?

How it works

Underneath the MP1’s saddle-shaped wooden deck are two welded steel frames, one that supports the deck itself, and the other that rests on the ground. In between is a set of tracks and rollers that provide 24cm of fore-aft movement and up to six degrees of sideways tilt in either direction. Both motions are self-centering: the fore-aft glide via gravity, thanks to the way the roller tracks are gently curved; and the side-to-side tilting via a hefty steel leaf spring.

Integrated into the top of the wooden deck are a variety of indexed metal channels that pair with meaty Velcro straps to secure your indoor trainer of choice out back, along with a stout molded plastic wheel cradle to support your front wheel. Two risers are included to ensure your bike is level front-to-back, while adjustable feet down below do the same for side-to-side tilt of the motion platform itself.

Underneath the plywood platform is a double welded steel frame with a complex arrangement of rollers, tracks, pivots, and springs. The quality of the motion is superb, but I do wish that Saris had used an aluminum frame so as to make the MP1 a little easier to move around.

Thankfully, almost all of this is fully assembled at the factory, so while you can readily flip the MP1 platform over to check out what’s going on at the business end, you don’t actually have to put any of the important stuff together yourself. After opening up the rather massive (and heavy!) cardboard box, all you have to do is attach the front wheel block and the rear straps, and apply some silicone lubrication (which is included) to the roller tracks down below. In all likelihood, it’ll take you longer to break down all of the cardboard packaging and stuff it into the recycling bin than it will to get the MP1 ready to use.

Saris obviously would prefer that you pair the MP1 with one of its own stationary trainers, but the platform is designed to accommodate just about any trainer model on the market. Getting everything mounted up is pretty straightforward, too, thanks in no small part to the handy online fit guide that Saris has on its web site.

What it’s like to “ride”

I wasn’t entirely sure what to expect of the MP1, to be perfectly honest. Would that little bit of motion really be that significant? I’d certainly been intrigued after briefly sampling the prototype at Eurobike a few years ago, and again after tossing a leg over a production sample during a visit to Saris a couple of months ago, but the question remained whether a longer-term test would seem as revolutionary as Saris makes the MP1 out to be.

After several weeks on one, I perhaps wouldn’t characterize using the MP1 as some sort of indoor cycling awakening, but it absolutely does add to the experience.

There’s minimal movement in any direction in most seated situations — sort of like a subtly rhythmic swaying — although the amplitude will ultimately depend on the quality of your pedaling action. Mine is fairly decent, but if I made a point of pedaling in “squares”, there was definitely more noticeable motion, mostly in the fore-and-aft direction.

The arc of the tracks was specially chosen to provide a realistic-feeling amount of self-centering as your weight shifts fore and aft. The steel tracks move on hard plastic rollers. Periodic lubrication of the tracks with silicone is recommended by Saris for continued smooth operation.

Rising out of the saddle was far more interesting, of course, with much more movement in both directions with each pedal stroke. The bike tilts beneath you — to a pretty significant, yet realistic, angle — and you become far more aware of just how much your center of gravity shifts around with your changing body positions. All of the motion is impressively smooth, fluid, and quiet, and the effort Saris went through to carefully tune the MP1’s spring rates, pivot locations, and roller track shapes has clearly paid off.

Dare I say it, but the whole does feel quite realistic, and if your indoor setup incorporates a larger-than-life TV and a high-powered computer to process the video, it makes for a surprisingly immersive experience. Will anyone mistake this for riding outside? Well, no. But as far as realistic-feeling indoor riding goes, incorporating a motion platform like the MP1 is clearly a step in the right direction.

There were a few unexpected benefits as well.

Saris claims that adding motion to the mix makes riding indoors more comfortable, and I’d now tend to agree with that assessment. Whereas I normally feel the need to periodically shift my weight around a bit or stand up to take pressure off the saddle, I found that I could stay seated for longer when using the MP1 than I normally would when riding indoors, much like I would when out on the road for real.

The deck is made of laminated plywood with a birch veneer. There’s an ample amount of grip tape applied to keep hard plastic cleats from slipping around.

Interval and sprint workouts felt more effective, too. Even with the best indoor trainers, I still find that they’re not always as stable as I might prefer. But with the MP1’s enormous footprint, coupled with the fact that it’s allowing you to move normally as opposed to resisting that movement, I was more confident thrashing about without worrying about tipping the whole thing over.

Interestingly enough, what I noticed most about the MP1 wasn’t what it added to my indoor cycling experience when I first started using it, but more what was missing when I switched back. As the saying goes, you don’t know what you’ve got until it’s gone, and in the case of the MP1, it’s perhaps best not to get too well acquainted with it unless you’re prepared to take one home — and as I said, these suckers sure aren’t cheap.

Not quite infinity and beyond

The luxury of spending several weeks with the MP1 Nfinity motion platform may have enhanced its appeal in my eyes, but it also revealed a number of quirks that are worth mentioning.

First and foremost, the MP1’s side-to-side tilt feature is neat, but there’s a learning curve involved with getting the most out of it. On the road, when you’re out of the saddle and apply power to your right foot, you naturally lean the bike left to keep going straight, and vice versa. But on the MP1, the motion is actually opposite — when you apply power with your right foot, the bike and platform want to lean right. It’s only once you remind yourself to engage your arms into the action that you flip things back to normal, and it’s not entirely obvious at first that you need to do so.

The hard plastic rollers work quite well, but they also seem to be a little brittle. My first MP1 test sample arrived with two broken rollers despite the fact that there was no visible damage to the shipping crate, which makes me worry a little about the long-term durability.

Getting the MP1 Nfinity truly dialed in takes some time, too.

The underlying mechanism on the MP1 makes for impressively low-friction movement, but it’s also sensitive to disparities in weight balance. Positioning your bike right along the platform’s centerline is simple enough (although a visual marker would be handy). However, not all higher-end smart trainers are symmetrical, and those hefty flywheels can really throw things off. Ironically, I had some of the most trouble with Saris’s own H3 model, whose center of gravity sits decidedly left of center. The adjustable feet on the bottom of the MP1 allow you to counteract that so you’re once again sitting perfectly upright, but it still took a few tries to get it perfect.

Speaking of that H3, its off-center design also placed it curiously close to the left edge of the MP1’s platform. I was never in fear of it actually falling off — those hefty Velcro straps do their job — but it’s something to keep in mind, and something I’m surprised Saris didn’t address more with the MP1’s final design.

“Accommodating the widest range of trainers possible was a significant challenge, and ironically, the H3 was one of the hardest because it has the biggest footprint,” explained Saris director of consumer product, Jesse Bartholomew. “We did consider making the MP1 a bit wider, but we maxed out dimensions for shipping.”

Speaking of dimensions, the MP1 really is a seriously big and heavy piece of equipment. Using steel frames instead of aluminum ones cuts down on cost, but also adds mass, as does using a plywood deck with a birch veneer instead of the real deal (although engineered wood is admittedly more likely to stay flat over time). Actual weight for the complete MP1 setup is a substantial 30kg (65lb), plus, the moving bits make it awkward to transport. On the plus side, the roughly 16cm (6.5in) thickness (without the front-wheel cradle) is thin enough to slide under a lot of beds, as long as there isn’t a support post in the middle.

Rear-wheel trainers that are asymmetrical in terms of left-right balance will require a bit more care in terms of setup. In this case, the Saris H3’s hefty flywheel causes the MP1 to tilt to the left, requiring some adjustment to the rubber feet down below to keep things level.

Neither of those concerns will be a big issue for people who have a dedicated space for their indoor training setup. But for riders that need to set things up — and then put everything away — every time they ride indoors, the MP1 is an awfully unwieldy beast.

And then there’s the question of how well the “sealed” plywood deck will hold up after being repeatedly drenched in caustic sweat for months and years. To be honest, I can’t answer that question since I simply didn’t have it long enough to tell. But “sealed” or not, we’re still talking about wood here, and wood and (salt) water don’t exactly have a history of getting along well without regular cleaning. I’d recommend putting a towel down just to be safe, and making sure to wipe the MP1 surfaces down as often as you can tolerate if you plan on holding onto this thing for the long haul.

Die-hard indoor riders who already have a complete setup might also like to know that there’s no good way to mount a Wahoo KICKR Climb device up front in lieu of the fixed front-wheel cradle. That’s hardly a surprise that Saris didn’t go out of its way to accommodate a direct competitor, but it’s a bit of a bummer nonetheless.

And finally, there’s perhaps the elephant in the room: Kurt Kinetic. That company has offered indoor trainers with integrated side-to-side motion (but not fore-aft) for well over a decade now with no additional costs or equipment required, and even at suggested retail pricing, its top-end R1 direct-drive smart trainer is substantially cheaper than the MP1 alone, let alone the trainer that you still need to put on top of it.

Does the Kurt Kinetic R1 feel as “real” as the MP1? Well, no, it doesn’t. But the price disparity is so great that you’d be silly not to at least consider it.

So luxurious, but still very much a luxury item

The Saris MP1 Nfinity platform is absolutely a super intriguing apparatus, and one that dedicated indoor riders with deep pockets would do well to consider to enhance their indoor riding experience. It feels more natural, it really does improve comfort, and — truth be told — it’s actually just kind of fun. From a purely functional perspective, the MP1 is a winner.

But do you need it? Of course not. And man, is it an awful lot of money.

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