Chisel...with a small hand air pump and a couple of nylon rim tools ...you can change out a tube pretty quickly with quick release rims and cantilevered brakes, and be back on the road...for me it's easier to replace with a new tube than try to patch as the glue when once opened doesn't usually last....down here we have a weed called a sandspur, and the dried burrs can puncture a tube pretty easily... since changing to a heavy duty thorn proof tube, have not had a problem... there are kevlar belts available to protect the tube...

as AFLM commented, the articulated rear suspensions use up a lot of energy...if you run across a GT with a solid aluminum block in place of the elastic absorber, ask whoever stole it to return it...I miss it...