It’s hard to believe that it’s been almost five years since Project 321 launched their magnetic drive system at NAHBS. Now, that clever magnetic pawl system has found a new home—in the shells of Stan’s new M-Pulse hubs. Developed to eliminate freehub drag while coasting, Stan’s is completely invested in the idea and will offer it on almost all of their mid to high-level products.

Stan's M-Pulse hubs with Project 321 magnetic pawls

You may be asking yourself, “OK, magnets. But how do they work?” Instead of a traditional pawl spring design, where tiny springs physically push the individual pawls into the engagement ring, these hubs use magnetic pawls. The six hardened steel pawls are fitted with neodymium rare earth magnets which pull the pawls into the hardened steel drivering rather than push.

Both Project 321 and Stan’s point out that this provides the system a unique advantage over traditional springs. The magnetic force on the pawls gets stronger as they get closer to the drivering and weaker as they coast, which helps to reduce drag. On the flip side, traditional spings are weakest when they’re extended, pushing against the drivering, but stronger when compressed. Because of this, Project 321 and Stan’s claim that this system offers a significant reduction in drag and friction with reliable engagement.

Stan's M-Pulse hubs with Project 321 magnetic pawls

Stan's M-Pulse hubs with Project 321 magnetic pawls interior view

And at 216 points of engagement which works out to 1.66° of rotation, they’re very quick to engage as well. Those who are familiar with the Project 321 system may notice that Stan’s isn’t offering a ‘quiet version’ of the pawls. Instead, they’re sticking with the louder versions which offer more teeth on each pawl for more secure engagement with the drivering.

Stan's M-Pulse hubs with Project 321 magnetic pawls rear hub

Rather than the typical press-fit end caps, Stan’s has chosen an adjustable preload system with a burly 17mm 7075 aluminum axle with custom-filled Enduro bearings. Extensive testing resulted in a double-row main freehub bearing which was found to offer more durability, and all bearings are shielded, keeping all of the bearing seals hidden from the elements.

For the Stan’s M-Pulse hub build, all freehub body shells, magnetic pawls, ratchet rings, spacers, and axles are manufactured in Bend, Oregon at Project321’s CNC shop. The hubs are then assembled in Big Flats, New York at Stan’s headquarters using Asian-made hub shells. The result is a high-quality hub with US-Made guts and a 5-year warranty from Stan’s.

Stan's M-Pulse hubs with Project 321 magnetic pawls hub set

While the front hub is fairly simple by comparison, it too will feature an adjustable preload. Hubs will be offered in 6-bolt or Centerlock brake configurations, and with Shimano Micro Spline, HR, or SRAM XDR freehubs.

Stan's M-Pulse hubs with Project 321 magnetic pawls MK4 wheelset

Offered as part of complete wheelsets, M-Pulse hubs will start at $965 for the set with Stan’s MK4 Asymmetric rims including the 30mm wide Flow MK4, 28mm wide Arch MK4, and 25mm wide Crest MK4 which were launched last summer (now we also know the details of that secret hub that was teased). Stan’s also states that M-Pulse hubs will come standard on all carbon CB7 and Podium SRD wheelsets which start at $1,987. We love to see that for every wheelset equipped with M-Pulse hubs that Stan’s sells, they will donate $10 to the local trail group or cycling charity of your choice.

The only wheels that won’t have the M-Pulse hubs will be the DH/Enduro EX3 and more affordable S2 wheels. Those will use the new E-Sync hub which is a heavier duty, e-bike rated hub that offers a 47% higher torque rating than their previous Neo hub.

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Giraffe King
Giraffe King
4 months ago

Damn, no quiet version ?!?! I was ready to send my money.

Justin Walsh
Justin Walsh
4 months ago

Disappointing for sure. 321 has been without the quiet option for about a year, and I was hoping they were back when I was this headline.

None Given
None Given
4 months ago

I seriously have to wonder if the magnets will mess with the pickups on so many of the ebikes (Specialized I know has magnets right in that area)…maybe I am a jerk, but I hope they do 🙂

Tim kennedy
Tim kennedy
4 months ago

Yeah I’m going to have to wait till there’s a silent version how unfortunate.

carbonfodder
carbonfodder
4 months ago

I am going to ask a potentially stupid question…. How is a magnet any better than a spring when coasting? according to the article (and seat of the pants logic), magnets are stronger when closer and springs are weaker as they extend. If indeed that is the case (and my tiny brain would agree), then the drag on a magnet based freehub should be much higher than that of a spring based freehub while coasting, simply because the pawl magnet would be “seeking” a drive ring peer, thus forcing the pawls into the drive ring as much as possible. In the case of a spring, the under-pawl magnet would be pretty weak at extension and thus offer less resistance. Assuming I don’t have my head in my butt, then the spring would be a ‘better’ (less resistive) solution for freewheeling.

Note that I would be fully in agreement with magnets being better under a drive scenario, but I just can’t make freewheeling a win for the magnets.

Can somebody clarify where my (il)logic falls down?

Raf Tor
Raf Tor
4 months ago
Reply to  carbonfodder

You are correct in stating that you do not understand what they are are trying
to say. Just keep reading the article until you get it. Just keep in mind that the pawls are farther away from the magnets when coasting so there will be less pull on it therefore less friction. There is more push on the pawls downward while coasting with springs, therefore more friction.

Ol' Shel'
Ol' Shel'
4 months ago
Reply to  Raf Tor

They need to put up some numbers. Otherwise, it’s just a baseless claim.

Ron
Ron
4 months ago
Reply to  carbonfodder

Hey brother; imagine the pawl in full engagement up into the outer ring. This condition is for torque.
Now imagine the pawl rotated in towards the center axis, it disengages & allows freewheeling

now the magnet is located at the end of the pawl. The spring located under the pawl seated toward the axis.

now when the pawl is up in the drive ring for torque, the magnet touches the receiver giving it the most force. The spring would be at full extension to drive the pawl up, lessening it’s force. Is the spring force harder at spring extension or compression: compression since it uses a compression spring: so the magnet is max force when pawl engaged; the spring is extended and not at max force

when freewheeling, the pawl rotates toward center; the magnet now has an increased air gap so the force or flux is weaker. This gives less friction as there is less rubbing force. Contrary, the spring is fully compressed then the pawl is rotated toward the axis for freewheeling. This compression increases the spring force; this the rubbing force and friction are increased

got it?

Ol' Shel'
Ol' Shel'
4 months ago
Reply to  Ron

How much force is needed to hold the pawl in the engaged position? Not much. Under pedaling force? None.

So, either a spring or magnet will need sufficient force to re-engage the pawl during transition from coasting to pedaling. Once it does that, which requires very little force, little-to-no additional force is required. More force than it has initially, as the magnet idea promises, doesn’t seem like any advantage at all.

Bard
Bard
4 months ago

Available on their own from Stan’s or only the big $ version from 321?

Xc_racer
Xc_racer
4 months ago

Looks like the hub is only engaging 2 pawls at a time (according to info from the 321 website).

I also understand that they would have less drag due to the magnets pulling instead of pushing, but at the same time, the pawls are kept in place by the tooth profile pulling them in under load, so the fact that the magnets offer more force when they are engaged is kind of moot.
I’d think you want the most force at the point where the pawl just starts to engage the tooth to ensure it’s properly engaged every time and not going to skip.

Time will tell how reliable they are.

Ed B.
Ed B.
4 months ago
Reply to  Xc_racer

Time has told how reliable they are. I’ve got a set that is 4 years old and over 4k miles now.

Bubbrubb
Bubbrubb
4 months ago
Reply to  Ed B.

absolutely not casting doubt, but especially in mtb, local ride scenarios vastly skew longevity… mud and rocks vs dry smooth trails… curious if the magnets attract iron/steel particles?

Mark Studnicki
Mark Studnicki
4 months ago

They explained the difference and how it effects drag exactly in the article

Chris
Chris
4 months ago

The biggest advantage that I see to using the magnets is for the person assembling the rear hub. No small springs to capture and try not to loose during the assembly procedure. Perhaps this upgrade is more for the builder vs the end user.

However the Enduro bearings and adjustable preload is a great upgrade for the user.

techy
techy
4 months ago

End user adjustable preload…..oh boy…..can’t even recall how many Zipp hubs with that same feature came in with destroyed bearings thanks to poor adjustments made by our clients, too loose or too tight.

ursusvelocipede
ursusvelocipede
4 months ago

@carbonfodder – you read the effect reversed … the magnets have less pull strength on the drive ring when coasting because the ramps has forced the pawls away, so there’s less force on the pawl/ring interface and thus less drag. Springs would be inverse, pushing harder as the ramps forced the pawl away away from the drive ring.

i’ll be interested to see how these stack up in real use, IMO the original neo hubs (2016/2017) were crud for strength & axle rigidity so hope these work out as they sound decent.

K-Pop is dangerous to your health
K-Pop is dangerous to your health
4 months ago

I would like to see an independent test of all these claims of low drag. The freehub is one aspect, but all hubs also have to deal with bearing drag under load. Has to be with load applied otherwise a test would be invalid. Can’t just spin it in your hand and call it good. Would be interesting to see a comprehensive comparison of all these hubs in the low drag wars. Anyone know of such a study?

Peter
Peter
4 months ago

Seems like they’re trying to have their cake and eat it too.

Friction is normal force (magnet/spring) times coefficient of friction. If the magnets are providing a greater pull when the pawl is dragging across the back side of the ring, then you get more friction.
Also, freehub friction is like 50th on the list of things that slow down a bike. At 15mph, 85% of your energy goes into air resistance.
One commenter did say that a (potentially) big upside is assemblely ease, and that might be true.

Paul
Paul
4 months ago
Reply to  Peter

This is where the confusion is. As has been pointed out in many other comments here, the feature of the magnet orientation is that the normal force is massively reduced when the pawl is not fully engaged. The force should decay linearly in relation to the distance cubed.

So as the pawl rides up the tooth, the normal force reduces to a minimum. The spring however has the minimum normal force when the pawl is engaged, and the maximum force when the pawl is riding over the top of the tooth.

Obviously the ratchet drag being the least of our worries is true!

Eric B
Eric B
4 months ago

@carbonfodder – quick explanation for you. When pedaling, the pawls are engaged, which means that they are as close as possible to the drive ring, they are physically touching. In a traditional spring, the spring would be more extended in this position, and thus there’s less force pushing the two together and thus less secure connection. With the magnets, the force is stronger the closer the two are, so in the engaged position the force is strongest for the most secure connection when pedaling. In practice, this difference is probably not noticeable, but hey it’s in the marketing and technically accurate.

Now, when coasting, the pawls will slide along the teeth of the drive ring, clicking over each tooth as the hub spins. In the spring model, as the pawl slides up a tooth, the spring becomes more compressed, making more sliding friction between the pawl and the drive ring. Then the pawl passes over the tallest point of the tooth, drops back down releasing the tension, and repeat. With the magnets it is reverse – the sliding friction becomes lower as the pawl travels up the tooth. Now I have no idea what the actual difference in friction would be, especially since the spring force would change linearly while the magnet force would not, but again technically the marketing is not lying.

charlie
4 months ago

Very curious how the seals hold up, the last thing I would want is for magnets to pull magnetic particles into a ratchet system…

ap
ap
4 months ago

LOVE my P321 quiet hubs. Very free spinning, and pretty quiet (not silent though. No interest in loud ones.

Ed B.
Ed B.
4 months ago
Reply to  ap

Agreed. Can’t wait for quiet pawls to return.

Kevin Peeters
4 months ago

Definitely waiting for quiet version.

Jason R Etter
Jason R Etter
4 months ago

I tend to read claims like “less drag” as bull unless they’re accompanied by test data. This is because if you have done the testing and they do have what is claimed…..why not post the data? So either they have not done the testing. Or the difference (in this case less drag) is so small as to be insignificant.

Deputy Dawg
Deputy Dawg
4 months ago

I’ve got the loud versions, and……they’re not very loud.They have held up well for over two years under more than a bit of Moab-style high torque, low cadence climbing.

Deputy Dawg
Deputy Dawg
4 months ago

I should also note that mine are laced up to some pretty light Astral Serpentine Carbon rims that have held up equally well over the same two years plus. Not a hiccup, and fast as shite.

Xc_racer
Xc_racer
4 months ago

@ Peter
I think the assumption is that the pawls skip over the tips of the teeth while freewheeling, instead of fully engaging each pawl into the drive ring. So it makes sense that there’s less drag during coasting.

But as I mentioned in an earlier comment – where do you need the most force?
The profile of the tooth of the pawl will keep it engaged in the drive ring, so you don’t need more force to keep the tooth engaged.
And the main concern with any pawl based hub is synchronized engagement. If one of the pawls doesn’t engage properly, it will overloads the remaining engaged pawls (in this hubs case – the single remaining pawl), which puts excessive radial load on the freehub body bearings, and can also cause damage to the freehub body (normally deforming the pawl pocket / making it deeper), which means the synchronization of the pawls will only get worse until the freehub body self-destructs.

Like I said, only time will tell how durable the turn out to be.

Jordan S
Jordan S
4 months ago

Project 321 had a huge failure rate with the quiet and even some of the loud pawl systems. Project 321 denies the quiet pawls ever had an issue, yet they have been conveniently “out of stock” for over a year now! Does anyone remember CrankBrothers spec’ing P321 Hubs in their Synthesis Wheelsets? Crank brothers dropped them because the hubs failed horribly and couldn’t warranty them fast enough. Project 321 needs to hire a real engineer before selling a poorly executed design to a reputable company. Good luck to whoever takes $2k gamble on these wheels!

Dan
Dan
4 months ago
Reply to  Jordan S

I’ve been on the P321 “quiet” pawls for 4 years. It is true that there were issues with the magnet’s falling out with the initial release; it happened to me twice in the first 12 months. Jake from
P321 (Owner) was great to deal with, sincere in his apology and the revised version has been going strong for 3 years with zero failures.

Pat
Pat
4 months ago
Reply to  Dan

I have had a set of 321 quiet hubs for 4 years and have had nothing but problems. 3 sets of pawls fail, seals leaking oil all over pads and rotors, crazy popping as pawls violently engage. I’ve spoken with Jake multiple times and was told in Winter of 2018 that a new redesigned hub was coming and he would swap it out. It never happened, and I’m stuck with this hunk of junk. If you want light and high engagement, go hydra. These are a total waste of money.

Franco
Franco
4 months ago
Reply to  Jordan S

I’m going to buy a Synthetis weelset with P321hub but I read about some initial issues in these days….
I wrote to P321 and they said that they never made any change to
what we supplied to Crank Brothers.
You have other information about these issues? You know someone who have Synthetis with P321 hub that had problems?

Jordan S
Jordan S
4 months ago
Reply to  Franco

Where are you purchasing the wheel-set with P321 hubs? CrankBrothers has officially stopped building wheels with their hubs.If you find a set, they are old stock that will be riddled with problems. I would only order them if you can get at least a 30% discount. Email Crank Brothers and ask them what the warranty on the old P321 hubs would be, if you have issues.

Franco
Franco
4 months ago
Reply to  Jordan S

This is CB answer to my mail:
“We all run the P321 hubs here and they really are a nice hub, but the global coverage for warranty and parts was lacking a bit, so that was a big reason why we continued to go with I9 as a whole. We do still have some hubs and can use those for parts if need be, but I’m not sure if Pippo (italian service center) is going to stock P321 parts any longer.
Worst case scenario, we would replace your hub with an I9 Hydra since that is going to be the best we can offer down the road.”

I’ve found a set in a United Kingdom online shop (I’m from Italy) that cost 1.500€ (1.700$) so with 30% discount

buldog
buldog
4 months ago

Its no lower drag – even if it is it has no effect on performance in real world. Like ceramic bearings VS steel – only difference is in money you throw away. Difference here is that with time pawls will wear and dust from them will stick to magnets. Also in service they must be carefull if they will clean pawls with ugly cloth some metal particles will stick to magnets. For me stupid idea.

Tom
Tom
4 months ago

Less friction when coasting – basically means F- all.

James
James
4 months ago

Is that a freaking ICP reference?