B-Side (27.5″ / 650b 2017) [Archived]

[RETIRED. Replaced by the Riff model in 2018]

The B-Side is our hardtail frame for 27.5"/650b wheels. This 4th generation B-Side is more versatile than ever. Snazzy Tange/IRD Sliding Dropouts allow you to go single-speed or geared. A modified chainstay allows fiting even some double cranks with "plus size" 2.8" wide tires without needing to invest in Boost parts. We even offer a belt-drive ready version.

- Tange Prestige heat-treated butted CrMo steel; butted CrMo rear end

- Disc brakes only (no canti studs)

- Standard or belt-drive versions available

- Tange/IRD Sliding Dropouts allows geared and single-speed builds with easy wheel removal

- S-bend seatstays and chainstays

- Low sloping top tube/short seat tube

- Geometry is optimized for 100mm travel 27.5" forks and will handle 120mm forks great too

- CNC-machined 44mm headtube: Will take 1-1/8" steerers with a ZeroStack 44 headset or tapered steerers with a ZS44 upper assembly and external cup (EC44) lower assembly

- 27.2mm post size/28.6mm frt. der. size/29.8mm(or 30.0) seat collar, 73mm bottom bracket (English threads); 400mm+ post recommended

- Recommended tire size: 27.5 x 1.95 - 2.8”

- Color: Fiery Red

- Wt: 5.1 lbs.

- Sizes: SM(14.5"), MD(16.5"), LG(18.5"), XL(20.5")


B-Side (27.5″ / 650b 2017) [Archived]

  • Who would you recommend trying 650b/27.5" mountain bikes? [The 650b wheel size (27.5") is an established tire size, but is relatively new to the MTB market. It is sits almost in the middle between the standard 26" and the newer 29" tires.]

    This is a tough thing to give an explanation to especially to someone who has only ridden 26" wheeled mountain bikes. To these folks there isn't anything deficient with 26" wheels at all. That's how the collective mountain bike community felt before the 29er came along and we had something different to compare it to.

    And for the last few years, we've had folks that swear that the 29" wheel is the best MTB invention since the suspension. And others who've tried it and hate it. And we have some that own both types of bikes. It is from this paradigm, we make the statement that one tire size does not ideally suit every rider.

    We feel the 650b to be the "happy medium" between 26" and 29".
    Who do we think should try 650b?
    1) Those who feel 29ers were a little to unwieldy and slow to accelerate.
    2) Those who liked the 29ers rolling advantage, but didn't want to give up the steering quickness of a 26" bike.
    3) Those who want big wheel benefits, but find most 29er frames are a little too big for them.
    4) Those who find 29er wheels a little heavy. 650b will be noticeably lighter.
    5) At one time we would've recommended that if you are 6' 2" and over you are better off with a 29er, but we know of a couple of folks who are over 6' 2" and prefer 650b over 29ers (at least with full suspension bikes). And we also know women under 5' 5" who love their 29ers. Really it boils down to ride style and personal preference.

  • Sizing information you should know:

    If you normally ride a 17”, you may fit the 16.5” B-Side (400mm seatpost recommended).
    Bottom bracket shell: 73mm with English threading (updated spec for 2017)
    Seat collar size: 29.8 - 30.0mm
    Seatpost diameter: 27.2mm
    Front derailleur clamp diameter: 28.6mm