Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 150 Post(s)
The first issue is the valve stem type. If your bike needs the narrow presta valve stems, a fatter shrader valve inner tube won't fit.
The second issue has to do with tire width. Most of the 27" inner tubes that I've seen were designed for 27 X 1 1/4" tires - about 32mm wide. If you're running comparatively narrow tires you may have trouble cramming all of that inner tube into the tire carcus without pinching the tube under the rim.