Brompton G Line Tubeless Conversion Kit

Brompton G Line Tubeless Conversion Kit

• 2 x 60ml bottle of Schwalbe Doc Blue tubeless sealant (one per tyre)
• 3 x Schwalbe tyre levers 
• 2 x 40mm Schwalbe presta tubeless valves 
• 1 valve core remover 

Installation:

Note: We suggest against using tyre levers when installing inner tubes and tyres to your Brompton. Although the tyre fitting may seem tricky, it's just technique to do it tool free - see the below videos for help. (Using tyre levers can often result in damage to the inner tube - pinching it when installing, or to the tyre bead, or both)

The G line rims come tubeless ready, so for a tubeless set up please follow these steps: 

1. Remove the tyre and inner tube
2. Wipe the rim to make sure there is no debris 
3. Please check the pre-installed rim tape is well seated 
4. Install the tubeless valves into the rim
5. Fit the O-ring onto the valve stem, then screw the lock nut on by hand
6. Put the tyre on the rim - make sure the rotation is correct 
7. Remove the valve core using the valve core tool 
8. Pump the tyre up to seat it - allow the air ut. 
9. With the valve at the 6 O'clock position and slowly insert the sealant into the site through the valve 
10. Reinsert the valve core and tighten using the valve core tool - do not over tighten 
11. Inflate the tyre to the required pressure, close the valve and add the valve cap
12. rotate the tyre to ensure the sealant is distributed evenly 
13. Go for a short ride once the tyres are installed to check there is no issues 

Brompton part number / part number history

Introduced by Brompton in early 2026

Brompton 2020 Q part code: Q103754