OneUp Components

ISCG05 Underbash

  • SALE
  • Regular price £49.50
VAT included.

If you don't need a chain retention device, or your bike has an integrated chain guide, you can still add some bash protection with the OneUp ISCG05 Underbash.

The Underbash includes 3 different sizes of bash plate for compatibility with chainrings from 28-36T. Designed for frames with 2 ISCG05 tabs only (Deviate, Evil, Rocky Mountain, etc). Should not be used on frames with 3 ISCG05 tabs. Check with your frame manufacturer to be sure the tabs are strong enough. We run these on our Deviates with no problems.


  • Install without removing your cranks.
  • Single tool install and adjustment.
  • Boost compatible.
  • Oval compatible
  • Stainless Steel hardware
  • Includes 3 bash plates (28-30T, 32-34T, 36T)

Underbash Setup Instructions

    1. Hold backplate directly against ISCG05 tabs. Check for clearance between the back side of the bashplate and the bike frame (use included 2.5 mm spacers if necessary to space the backplate away from the frame).
    2. Rotate backplate to desired location and torque bolts to 5Nm

Bash Replacement Instructions

    1. Remove Underbash from bike
    2. Remove bolt retaining clip from rear bash plate bolt by pushing a 4 mm hex through the bolt from the backside of the Underbash.
    3. Remove Bash bolts using a 5 mm hex
    4. Select desired bash plate and reinstall bash bolts to 6Nm
    5. Reinstall bolt retaining clip on the rear bash plate bolt
    6. Reinstall Underbash onto bike

  • Weight: 68g 32-34T
  • Capacity: 28-36T
  • Chainline: 2.5 mm adjustment.
  • Mount: ISCG05 2-Bolt ONLY
  • Colour: Black
  • Material: 7075 aluminium, glass reinforced thermoplastic.

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