Crotchet Type Rims?

Paul said:

I've just bought a pair of new tyres online, Vredestein Scarabs. The inflation range is marked on
the tyre as 3 to 5 bar with a warning that says over 4.5 bar crotchet type rims only. I've never
heard this term before, what exactly are crotchet rims and how do I tell if I have them, equally
what happens at over 4.5 bar on non-crotchet rims.? I'd just assumed that rims were either
clincher or tubeless.

This, and many other cycling terms, is explained in my Bicycle Glossary.

See: sheldonbrown.comgloss cn z.htmlOpen ↗

Quoted message said:

The rims on by bike are relatively cheap Rigida Alloy.

Not to worry, they'll be fine.

Quoted message said:

Secondly I'm moving down from 1.95 width tyres to 1.75, am I likely to need new tubes. On most
tubes I've seen, any usable for 1.95 tyres include 1.75 in their range of use but I'd like to
be sure.

Not likely to be a problem, unless the tubes need to be creased to fit.

Sheldon "sheldonbrown.comglossaryOpen ↗" Brown +------------------------------------+
| Experience is a hard teacher, | because she gives the test first, | the lesson after. --
| Vernon Law |
+------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone 617-244-9772
FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find parts shipped Worldwide
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Yes, that explains it perfectly.

Many thanks.

Paul