Applies to: SB140 29" frames, model years 2023 and newer.
The SB140 is a 29" bike with 140mm of rear travel. This article covers SB140 frame specs, part compatibility, suspension setup, and warranty.
SB140 frame specs
- Rear travel: 140mm
- Wheel size: 29"
- Frame sizes: SM, MD, LG, XL, XXL
- Recommended fork travel: 150mm or 160mm (tested up to 180mm; max axle-to-crown 595mm)
- Rear shock size: 210 x 55mm
- Shock hardware: front M8 x 36mm; rear Yeti shock eyelet spacer
- Bottom bracket: threaded BSA 73mm
- Rear hub spacing: 148 x 12mm Boost
- Rear thru axle: 172mm long, M12 x 1.0 thread pitch
- Derailleur hanger: SRAM Universal Derailleur Hanger (UDH)
- Chainline: 55mm Boost. For SRAM cranks, use SRAM DUB Wide (CL55).
- Chainring size: 28T to 34T round, or 30T to 32T oval
- 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 frame and part compatibility
What size seat post and seat collar does the SB140 use?
The SB140 uses a 31.6mm seat post and a 36.4mm seat collar.
Can I run an internally routed (stealth) dropper post on the SB140?
Yes. The SB140 has routing for stealth (internally routed) dropper posts only.
What is the longest travel dropper post I can run on the SB140?
The longest SB140 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 150mm drop on SM frames, 175mm on MD frames, and 200mm on LG to XXL frames.
What travel fork is the SB140 designed to use?
The SB140 is designed for a 150mm or 160mm travel fork. Yeti tested the SB140 frame to 20mm over the spec fork, so you can run up to a 180mm fork. The maximum axle-to-crown measurement is 595mm.
- 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.
Can I use an angleset on the SB140?
No. The SB140 has an integrated headset with the headset cups molded into the frame. Some aftermarket anglesets fit this headset style, but the SB140 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?
The SB140 works only with SRAM's Universal Derailleur Hanger (UDH) axle at 12 x 148mm spacing. The axle is 172mm long with a 12 x 1.0 thread pitch. This axle only fits frames designed for the Universal Derailleur Hanger.
What cranks and bottom bracket can I use on the SB140?
The SB140 uses a BSA 73mm threaded bottom bracket and is compatible only with wide q-factor cranks. Shimano, SRAM, and RaceFace cranks fit; other brands need a fit check.
What chainline was the SB140 designed around?
The SB140 was designed around a 55mm Boost chainline. Other chainlines may work depending on the crank and chainring, but check clearance first. The minimum clearance from the chainring teeth to the chainstay is 3.5mm.
What is the largest chainring that fits on the SB140?
With Shimano or SRAM 55mm chainline Boost cranks, the SB140 fits up to a 34T round or 32T oval chainring. The minimum is 28T round or 30T oval. The limit depends on crank chainline and chainring shape, with at least 3.5mm of clearance between the chainring teeth and the chainstay. Not sure? Ask your local Yeti dealer or contact Yeti Cycles support.
Does the SB140 have ISCG mounts?
Yes. The SB140 has integrated 3-bolt ISCG '05 mounts. The SB140 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?
The SB140 runs a 180mm rear rotor without a brake adaptor. With a brake adaptor, the SB140 fits up to a 203mm rear rotor.
How big a tire can I fit on the SB140?
The SB140 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 front triangle?
Yes. SB140 sizes LG to XXL fit a standard water bottle inside the front triangle with a piggyback shock. Sizes SM and MD fit a standard 21oz bottle with a piggyback shock. A side-entry cage gives the easiest access.
Can I convert the SB140 to a mullet (27.5" rear wheel)?
It is possible, but Yeti does not recommend it. A 27.5" rear wheel on the SB140 lowers the bottom bracket too much and slackens the head tube and seat tube angles. If those changes suit your riding style, it is your call.
SB140 suspension setup
What shock does the SB140 use?
The SB140 uses a 210 x 55mm rear shock. Some shocks can be locked out, but Yeti recommends running the SB140 shock fully open for the best compliance and traction.
What shock hardware does the SB140 use?
The SB140 uses M8 x 36mm hardware on the air can 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?
Yes. The SB140 works with both air and coil shocks.
What sag should I run on the SB140?
Start the SB140 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.
SB140 parts, upgrades, and warranty
Can I upgrade the components on my SB140?
Yes. Many aftermarket parts fit the SB140, and parts from major brands like Fox, Shimano, and SRAM are largely standardized. Have a professional mechanic confirm each part matches the SB140's standards and mounts securely without interference or play. Check the fit before riding.
Can I replace or modify Yeti frame parts on my SB140?
Use only genuine Yeti replacement frame parts on the SB140. 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 SB140 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?
The SB140 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.