John the Canuck
..a long way from somewhere called Home..
- Location
- Strathaven, Lanarkshire
older steel wheels with straight-sided rim
RIGIDA 28 x 1-5/8 x 1-1/8 700C
Continental ULTRA Sport 700 x 23C
I've always had trouble mounting these - difficult to get all of the bead to sit up on the rim shoulder
- even at 120psi - a section of the tyre sits 'down' below the marker strip
reading Sheldon......... '' tyres should be 1.45 to 2.0 x the 'inner rim width'...''
so, off with a tyre - and the inner rim width IRW - 17.6mm
equals a tyre between 25.5 and 35.2.......
on his chart page
IRW of 15cm = 23C tyre
IRW of 17cm = 25C tyre
IRW of 19mm = 28C tyre
so could my 23C tyre not be wide enough to pop up onto the rim shoulder..?
appreciate your comments....
john
RIGIDA 28 x 1-5/8 x 1-1/8 700C
Continental ULTRA Sport 700 x 23C
I've always had trouble mounting these - difficult to get all of the bead to sit up on the rim shoulder
- even at 120psi - a section of the tyre sits 'down' below the marker strip
reading Sheldon......... '' tyres should be 1.45 to 2.0 x the 'inner rim width'...''
so, off with a tyre - and the inner rim width IRW - 17.6mm
equals a tyre between 25.5 and 35.2.......
on his chart page
IRW of 15cm = 23C tyre
IRW of 17cm = 25C tyre
IRW of 19mm = 28C tyre
so could my 23C tyre not be wide enough to pop up onto the rim shoulder..?
appreciate your comments....
john