The Viral Bikes Skeptic is a radical departure from the norm, playing in a space that only few have ever dared. This play bike is built around a 120-140mm travel front fork, new Boost spacing rear triangle, and a Pinion drivetrain that effectively puts an end to poor shifting performance and drivetrain maintenance. Founded by Porsche gearbox engineers, Pinion is a cutting edge gearbox company building amazing bicycle transmissions in Germany. The Viral Bikes Skeptic frame kit will come stock with their P1.12 twelve speed internal gearbox transmission. This amazingly robust and nearly maintenance free system was borne to defy current mountain bike standards and laugh in the face of traditional drivetrains. It’s sealed, completely, from the elements and only requires a fluid change once every 6000 miles or once a year, whichever comes first. In addition, the Pinion gearbox comes with a 5 year guarantee that your shifting will be perfect, no questions asked, as long as the fluid is changed within the prescribed schedule. Coupled with the Gates belt drive, the Skeptic is nearly maintenance free. Just ride, rinse, and repeat.


wheel size26+/27.5"27.5+/29"27.5+/29"27.5+/29"
a seat tube length390390390432432432480480480520520520
b top tube length - effective*583584585604605606624625626644645647
c head tube length110110110115115115125125125140140140
d chainstay length**430430430435435435435435435435435435
E front and center*693696700712715718733736739755758761
F wheelbase*112011241128114111451148116211661170118411871191
G seat tube angle*74°73.5°73°74°73.5°73°74°73.5°73°74°73.5°73°
H head tube angle*68°67.5°67°68°67.5°67°68°67.5°67°68°67.5°67°
I stack*597600604638642645647651654661665668
J reach*411406401420415410437432427453448443
bb drop*383532585552585552585552
Units are in millimeters, click to view them in inches.
**measurement in the shortest position

• 30.9mm seatpost, internal dropper post cable routing compatible
• Internal (integrated) tapered headtube, IS42 upper, IS52 lower
• 148/12 Boost thru axle


  • Viral Bikes triple butted titanium tubeset delivers an amazingly defiant ride
  • 27.5+ (3” tire clearance) or 29” wheel compatible, tailor this trail machine to your own desires
  • Pinion P1.12 gearbox delivers 600% gear range, that’s 100% more gear range than the new SRAM 1×12 system
  • Comes with Gates belt drive and front and rear Gates cogs
  • 120-140mm fork compatible
  • 30.9mm seat post, compatible with internal dropper post routing.
  • 148mm Boost rear hub spacing
  • 4.25 lbs. for medium frame
  • $4,999 frame and drivetrain kit

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