Applies to: SB140 27.5" frames, including the SB140 LR (Lunch Ride), model years 2020 to 2023. The SB140 27.5" is a previous model and is no longer in the current Yeti lineup. For the current 29" SB140, see SB140 specs and FAQ.
The SB140 27.5" is a 27.5" bike with 140mm of rear travel and Switch Infinity suspension. This article covers SB140 27.5" frame specs, part compatibility, suspension setup, and warranty.
SB140 27.5" frame specs
- Rear travel: 140mm
- Wheel size: 27.5"
- Frame sizes: XS, SM, MD, LG, XL
- Recommended fork travel: 150mm or 160mm (up to 180mm; max axle-to-crown 577mm)
- Rear shock size: 210 x 55mm (Fox Float DPS on the SB140; Fox Float X on the SB140 LR)
- Shock hardware: front M8 x 36mm; rear Yeti shock eyelet spacer
- Bottom bracket: PF92 press fit
- Rear hub spacing: 148 x 12mm Boost
- Rear thru axle: 171mm long, M12 x 1.5 thread pitch (Yeti or Shimano E-Thru)
- Front derailleur: none (1x drivetrains only)
- Chainline: 52.5mm Boost
- Chainring size: 28T to 34T round, or 30T to 32T oval
- Chain guide mount: ISCG '05
- Headset: integrated 41mm/52mm tapered
- Seat post diameter: 31.6mm
- Seat collar: 36.4mm
- Rear brake mount: post mount, 180mm (no adaptor needed for a 180mm rotor)
- Rear rotor size: 180mm minimum, 203mm maximum
- Maximum tire width: 2.6"
SB140 27.5" frame and part compatibility
What size seat post and seat collar does the SB140 27.5" use?
The SB140 27.5" uses a 31.6mm seat post and a 36.4mm seat collar.
Can I run an internally routed (stealth) dropper post on the SB140 27.5"?
Yes. The SB140 27.5" has routing for stealth (internally routed) dropper posts only.
What is the longest travel dropper post I can run on the SB140 27.5"?
The longest SB140 27.5" dropper post depends mostly on your inseam. You can run any travel as long as the post is above its minimum insertion mark, your tire does not rub your saddle, and the dropper does not bottom out in the frame. Your local Yeti dealer can help you choose. Yeti runs a 125mm drop on XS and SM frames, 150mm on MD frames, and 200mm on LG and XL frames.
What travel fork is the SB140 27.5" designed to use?
The SB140 27.5" is designed for a 150mm or 160mm travel fork. Yeti tested the frame to 20mm over the spec fork, so you can run up to a 180mm fork. The maximum axle-to-crown measurement is 577mm.
- A longer fork slackens the head tube and seat tube angles and raises the bottom bracket.
- A shorter fork steepens the head tube and seat tube angles and lowers the bottom bracket.
What headset does the SB140 27.5" use?
The SB140 27.5" uses an integrated 41mm/52mm tapered headset, with the bearings inside the head tube for a lower ride height, simpler installation, and more stiffness.
Can I use an angleset on the SB140 27.5"?
No. The SB140 27.5" has an integrated headset with the headset cups molded into the frame. Some aftermarket anglesets fit this headset style, but the frame was not tested with them and they should not be used. Installing an angleset voids the Yeti warranty, and the customer assumes all liability.
What rear wheel axle fits on my SB140 27.5"?
The SB140 27.5" works only with a Yeti or Shimano 148 x 12mm E-Thru rear axle, 171mm long with an M12 x 1.5 thread pitch. The rear triangle is optimized for stiffness and weight with these specific axles. The SB140 27.5" does not use the SRAM Universal Derailleur Hanger (UDH).
What cranks and bottom bracket can I use on the SB140 27.5"?
The SB140 27.5" uses a PF92 (92mm press fit) bottom bracket and is compatible only with wide q-factor cranks. Shimano, SRAM, and RaceFace cranks fit; other brands need a fit check.
How many bottom bracket spacers do I need on the SB140 27.5"?
With a SRAM DUB PF92 bottom bracket and a SRAM DUB 52mm chainline crankset, use a 2mm clip-on spacer on the drive side and no spacer on the non-drive side. With a Shimano PF92 bottom bracket and a Shimano 52mm chainline crank, no spacers are needed.
What chainline was the SB140 27.5" designed around?
The SB140 27.5" was designed around a 52.5mm Boost chainline. Other chainlines may work depending on the crank and chainring, but check clearance first.
What is the largest chainring that fits on the SB140 27.5"?
With Shimano or SRAM Boost cranks, or RaceFace 52mm chainline cranks, the SB140 27.5" fits up to a 34T round or 32T oval chainring. The minimum is 28T round or 30T oval. Not sure? Ask your local Yeti dealer or contact Yeti Cycles support.
Does the SB140 27.5" have ISCG mounts?
Yes. The SB140 27.5" has integrated ISCG '05 mounts. It works best with low-profile modern chain guides; some older guides with larger upper guides may not fit. Always fit-check a specific chain guide before riding.
How big a rear rotor fits on the SB140 27.5"?
The SB140 27.5" runs a 180mm rear rotor without a brake adaptor. With a brake adaptor, it fits up to a 203mm rear rotor.
How big a tire can I fit on the SB140 27.5"?
The SB140 27.5" fits tires up to 2.6" wide. Actual tire sizes vary by manufacturer, so clearance can differ between brands.
Can I fit a water bottle inside the SB140 27.5" front triangle?
Yes. The SB140 27.5" fits a standard water bottle inside the front triangle, even with a piggyback shock. A side-entry cage gives the easiest access.
Can I convert the SB140 27.5" to a mullet (29" front wheel and fork)?
Yes, but a 29" front wheel and fork changes the SB140 27.5" geometry quite a bit. The head tube and seat tube angles get slacker and the bottom bracket gets higher. Some riders like these changes and some do not; it is your call.
Why are there rubber frame guards on the SB140 27.5"?
The SB140 27.5" has custom guards on the seat stay, chainstay, and down tube to protect the frame from rocks and roots and to keep chain slap quiet.
What is the difference between the TURQ and Carbon series SB140 27.5"?
TURQ series SB140 27.5" frames use Yeti's highest-grade carbon fiber for the best balance of stiffness, durability, and compliance. Carbon series frames use a modified layup with different materials to lower the price while keeping the strength and stiffness of the TURQ frame. A Carbon series SB140 27.5" frame weighs about 190g more.
SB140 27.5" suspension setup
What shock does the SB140 27.5" use?
The SB140 27.5" uses a 210 x 55mm rear shock: a Fox Float DPS on the SB140 and a Fox Float X on the SB140 LR. Some shocks can be locked out, but Yeti recommends running the shock fully open for the best compliance and traction.
What shock hardware does the SB140 27.5" use?
The SB140 27.5" uses M8 x 36mm hardware on the front (reservoir side) and a custom Yeti reducer on the shaft side. If you swap shocks, you can buy the Yeti shock eyelet spacer on yeticycles.com.
Can I put a coil shock on the SB140 27.5"?
Yes. The SB140 27.5" works with both air and coil shocks.
What sag should I run on the SB140 27.5"?
Start the SB140 27.5" at 30% sag, which is 16.5mm of shock stroke, for the best pedaling efficiency and terrain compliance. Set sag at your normal riding weight with your gear on. You can go slightly above or below 30% to suit your preference. The Yeti shock setup calculator gives starting settings for your shock.
How often should I service the SB140 27.5" Switch Infinity link?
Grease the SB140 27.5" Switch Infinity link every 40 hours of riding through its external grease ports. Do not over-grease it, and wipe off dust and dirt regularly. Grease and service parts are available from the Yeti webstore or your local Yeti dealer.
SB140 27.5" parts, upgrades, and warranty
Can I upgrade the components on my SB140 27.5"?
Yes. Many aftermarket parts fit the SB140 27.5", and parts from major brands like Fox, Shimano, and SRAM are largely standardized. Have a professional mechanic confirm each part matches the SB140 27.5" standards and mounts securely without interference or play. Check the fit before riding.
Can I replace or modify Yeti frame parts on my SB140 27.5"?
Use only genuine Yeti replacement frame parts on the SB140 27.5". You can get them from your local Yeti dealer or the Yeti webstore. Yeti cannot verify that aftermarket frame parts are safe on its frames. If any frame part is modified or replaced with a non-Yeti part, all warranties are void and the customer assumes all liability.
What is the warranty on the SB140 27.5"?
The SB140 27.5" frame and Switch Infinity link have a lifetime manufacturer's warranty against defects for the original purchaser from an authorized Yeti Cycles dealer. Paint and finish are covered for 1 year. Yeti will repair or replace, at its discretion, any frame it finds defective. To use the warranty, register your bike online at yeticycles.com and take it to an authorized Yeti Cycles dealer for processing. The warranty does not cover ordinary wear and tear, neglect, or intentional damage. See the Yeti Cycles Warranty for full terms.