Trim the edges of the damage to prevent further tearing. 

Trace the size of the patch, roughen the surface, and apply vulcanizing cement. 

Wait 3–5 minutes for the vulcanizing cement to cure (oxidize), then apply the patch. 

Use a roller to firmly press the patch onto the inner tube. 

Mark the damaged area 
Use chalk or a marker to clearly mark the damaged spot on the tube. 

Reinforce the tear 
If the damage is a cut, reinforce the ends by eyeletting to prevent further tearing. 

Clean the area 
Use Maruni Liquid Buffer to remove grease and dirt around the damage. Wipe it clean with a cloth. 

Trace the patch outline 
Place the patch over the damage and draw an outline slightly larger than the patch itself. 

Roughen the surface 
Mechanically roughen the marked area using a grinding tool or scraper to ensure proper bonding. 

Remove dust and debris 
Use a pneumatic vacuum or blower to completely remove all dust and rubber particles. 

Apply Vulcanizing Cement 
Evenly apply Maruni VALKARN Vulcanizing Cement to the prepared area. Wait until it fully dries (3–5 minutes, depending on conditions). 

Prepare the patch 
Peel off the aluminum backing from the patch. Avoid touching the active adhesive side. 

Apply the patch 
Place the patch exactly on the treated area. 

Press the patch firmly 
Use a roller to press the patch down from the center outward, pushing out any air bubbles. 

Remove the protective foil 
Peel off the top protective layer. The repair is now complete.