Bill experienced with that tyres the effect that the bead partially did not jump into the right position of the rim while mounting. Even with high pressure and soap water it is impossible to mount a mismatching tyre/rim pairing correctly.
Honestly I did not know that this effect applies also to the mentioned Schwalbe 40 - 305.
The effect can be explained by tolerances of tyre and rim.
Also are all borders of well-known “tyre to rim match” charts definitely not a must - the borders are floating.
The majority of riders will never notice something like this odd effect - simply because they are riding much bigger wheels (above 20"). But at least I am sure the effect becomes much more important the smaller the wheels are - I’ve noticed that mainly with 305 and 349 rim sizes.
One could say also:
- There is a reason for the cheapness of 16" LT plastc wheels; they are made to accept only the manufacturer’s tyres.
- Metal spoked 16" wheels wheel make less trouble - but the above mentioned effect MAY occur again with really fat tyres.
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