Accessibility Widget: On | Off

Project 321 Boost Rear Hub

Average User Rating: (Spectacular)
 Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub  Project 321 Boost Rear Hub
Create New Tag

Compare to other Rear Hubs

Need more info? View our MTB Rear Hubs buyer's guides.

Project 321 G2 BOOST Rear Hub

A top notch contender

Rating: Featured Member Review
Project 321 G2 BOOST Rear Hub
The Good:

High quality materials, Excellent Craftsmanship and attention to detail, Options for noise levels and p.o.e., An insanely high point of engagement, Light weight, Excellent customer service, 3 year warranty.

The Bad:

Nothing too much (See Possible Concerns)

Overall Review:

In the world of mountain bike components, there are some heavy hitters pumping out some high quality components. Specific towards hubs, some companies you may have heard from are Chris King, Industry Nine, Onyx, Hope, and Profile Racing. One company that you may not have heard from, yet has recently been turning quite a few heads, is Project 321. After that quick “Project 321” google search you’ll find their website which seems to be some sort of a hotchpotch of products ranging from car parts to keychains. But don’t let this diverse range of products fool you, they make a mean hubset that has recently had a performance facelift. Introducing the NEW Project 321 G2 Hubset.

Compared to their previous version (which used Industry Nine’s Torch Driver), the latest G2 version has completely move on to bigger and better things.


  • Weight: 280 grams (for BOOST 148x12mm)
  • Available axles: BOOST 148x12mm / 135mm QR / 135x10mm / 135x12mm / 142x12mm / 150x12mm / 157x12mm / 135 bolt on
  • Points of Engagement (p.o.e): 144 or 216 (2.5° or 1.66°)
  • Pawls: Quiet or Loud - 6 magnetic pawl system (No springs to wear out!)
  • Spoke Count: 32H and 28H patterns available now.
  • CNC engraved logo (not laser etch or sticker).
  • Warranty: 3 year for defects in materials or craftsmanship. (10 years for hub shells and axels)
  • Available in Standard Freehub Body or XD1 Freehub Body.
  • Available in RED, BLACK, BLUE, GREEN, GOLD and SILVER. Speciality colors available in PINK, PURPLE, ORANGE and TURQUOISE (with limited availability).
  • Made in the United States of Damn America.

Out of the Box:

Pulling these hubs out of their packaging, the first thing I noticed was the amount of detail that went into them. The anodization is top notch and every piece was designed with love. Spinning the axle and driver, I quickly realized that Project 321 wanted to rattle even the highest end hub manufactures in the industry when putting their G2 hub into production. Adding their custom CNC engraved logo on it tops it off as one of the most beautiful hubs on the market., here's actual weights.

PhotoClick photo to change size and caption

G2 Driver:

Now to get down into the nitty gritty of this new driver system. As mentioned previously, their previous driver was a licensed Industry Nine Torch driver with steal springs, 2 tooth pawls (x 6), and had 120 p.o.e. Their new driver has magnetic pawls, 2 tooth or 4 tooth pawls (x 6), and 144 or 216 p.o.e. which offers quite a bit more responsiveness to an already responsive freehub.

PhotoClick photo to change size and caption

The biggest durability improvement Project 321 offers with the new G2 hub is the magnetic pawls. It’s a fact of life that the older something gets, the less firm, the more droopy, and less desirable things become. This is true with tiny mechanical springs too. They may feel great for the first year or two but quickly lose their springiness (yeah, that’s a word). Companies that use such a system understand this and that is why they offer replacement springs to keep their hubs at peak performance. To get around this and increase the durability of their hubs, Project 321 inserted small magnetic chips into each pawl, which allowed them to do away with springs altogether. What this means is that you’ll have perfect freehub connection for years down the road, that is unless you ride around functioning MRI machines or are involved in an electromagnetic terrorist explosion caused by the Trump administration.

PhotoClick photo to change size and caption

Project 321 didn’t stop there. They also offer two types of pawls, one with 4 teeth which provides a loudness equivalent to if not slightly louder than Industry Nine and one with 2 teeth which, once loading the bored out hole in the drive chamber with oil, becomes quieter than knobby tires rolling on a sidewalk. And with the adjustment of oil, a rider can adjust the noise of the freehub anywhere in-between.

Loud pawls first, quiet pawls second.

In respect to freehub drag (the amount of resistance the freehub has when coasting), the drag of dry loud pawls seams similar to that of Industry Nine (which is significantly less than that of Profile Racing hubs) and the more oil installed, the less drag you get. The quiet pawls have such low drag that the hub shell stays in place as the freehub is rotated back in a truing stand (hub only)! No other higher end freehub that I’ve seen offers such low drag. This is what Project 321 stated about the drag of their new driver, “By using magnets as a pull spring (opposed to mechanical or magnetic push springs) to move pawls into the drive ring, we are able to achieve less drag and less noise than other high speed ratchet mechanisms. By using magnets in this configuration the pawl force against the drive ring is at its strongest when the pawl is fully engaged. As the pawl climbs the drive ring teeth during freewheeling the force (and friction) is reduced as the pawl magnets get farther away from the drive ring. This is the exact opposite of traditional mechanical push springs where the weakest point of the spring is at full engagement and the spring force gets stronger (creating more friction and drag) as the pawl is pushed up over the drive ring teeth during free wheeling.”

The first generation Project 321 hubs used the Torch interface. When revamping their freehub interface, Project 321 kept the hub shell measurements identical to the previous hub. This means that if you own the previous version, you can update your hub to the latest version. (Which Project 321 will install for $240; including shipping back to you.) With their generations of freehubs being compatible with each other, this means that you can actually install this new G2 driver into an industry nine hub shell; however, by doing so may void any warranty claims down the road and finding a company that will do it may be tough.


Although much of the functionality of these hubs has already been addressed above, there is one thing that I have to talk about. In addition to all the great things already brought up, the Project 321 hub comes with a pinch-bolt style through axle which locks the freehub in place. I know this doesn’t sound too impressive but there have been times where I’ve had to transport my bike by removing the wheels and after getting to my destination have discovered that my freehub had slid off of the axle and all those tiny springs were nowhere to be found. Although other companies use this same way of securing the freehub, Project 321 is the only one with the traditional pawl system that offers this to my knowledge.

Quick comparisons between highest-end hubs:


  • Project 321 G2 – 182g Front / 280g Rear (462g Set)
  • Onyx – 212g Front / 446g Rear (658g Set
  • Profile Elite – 222g Front / 363g Rear (585g Set)
  • Industry Nine – 155g Front / 280g Rear (435g Set)
  • Chris King – 166g Front / 341g Rear (507g Set)
  • Hope Pro 4 – 188g Front / 311g Front (499g Set)

Points of Engagement:

  • Project 321 G2 – 216 / 144
  • Onyx – Infinite
  • Profile Elite – 204
  • Industry Nine – 120
  • Chris King – 72
  • Hope Pro 4 – 44

Possible Concerns:

216 p.o.e. only has 2 pawls in contact at one time while the 144 p.o.e. has 3 pawls in contact (which is 33% less contact than the 3 pawls). While using the loud pawls which have 4 teeth per pawl, I don’t foresee using the 216 p.o.e. pawls as a durability concern. Putting a rider’s pedaling force on 2 quiet pawls which only have 2 teeth per pawl, seems like an awfully large amount of strain to put on 4 teeth total. Project 321 recommends that tandom, e-bike, and riders over 275 lbs only use the 144 p.o.e which has deeper, more developed grooves than the 216 p.o.e. To say that all other riders are able to use the 216 p.o.e. pawls is a confident statement to say the least. Followed by a 3 year warranty if any damage were to happen to the freehub interface can put quite a bit of this worry to bed but it’s still something to keep in mind.

Bottom Line:

The New Project 321 G2 hub has quite a bit of improvement from the previous version and has made it a major contender for the “Industry’s Best Hub Award.” The key points of these hubs are durability, options in points of engagement (p.o.e.) and sound, and weight. More points of engagement than Profile Racing, almost half the weight of Onxy (comparing rear hubs), and durability that is hard to match, the Project 321 hubset is a clear overall winner. The company itself is very easy to get in contact with although their website is currently lacking quite a bit of information on these new hubs. If you are looking for the latest and greatest for your next custom wheel build, put Project 321 on your list. Reach out to Stephanie at and tell her that I sent you! You will not be disappointed.


Product Project 321 Boost Rear Hub
Riding Type Cross Country, Dirt Jump / Slopestyle, Downhill, Freeride / Bike Park, Trail
Hub Body Material Alloy
Cassette Body Material Alloy
Rear Axle 12mm x 148mm (Boost)
Bearing Type Enduro ABEC 5 (includes angular contact bearings)
Hole Count 32h or 28h
Disc Mount Type 6 Bolt
Colors Turquoise, Black, Blue, Green, Gold, Silver, Pink, Purple, Orange, Red
Weight N/A
Miscellaneous Magnetic pull spring driver system featuring standard 6x2 (6 pawls with 2 pawl engagement) with 216 points of engagement (1.66-degrees), or 6x3 driver system (6 pawls with 3 pawl engagement) with 144 points of engagement (2.5-degrees).

*6x3 system only recommended for tandems, e-bikes and riders over 275lbs.

3-year warranty.
Price $390
More Info


More Products