'Illegal' gear combination.

[little dilbert]

A bike has for example, a rear cassette composed of 7 gears (cogs), and two gears on the front crank. I heard it would be 'illegal' to set the chain on the largest gear on the front crank and the largest on the rear cassette, or similarly a combination of smallest smallest.

I've searched google but can't find anything, also never heard of this before.

Can anyone explain what it means to have these 'illegal' gear combinations?

 

[deptfordmarmoset]

Not illegal, simply ill-advised because an excessively ''crossed'' chain will wear out your chain.

 

[Rickshaw Phil]

Not illegal, simply ill-advised because an excessively ''crossed'' chain will wear out your chain.

+1 to this.

 

[MattHB]

A 7 speed chain is quite resilient though. I'd not overly worry about it. Plenty of people ride to the extreme sides of the cassette in relation to front ring

 

[Nigelnaturist]

Wouldn't advise it on a triple.

 

[Noodle Legs]

Not illegal, simply ill-advised because an excessively ''crossed'' chain will wear out your chain.

Exactly as said here, I believe the term to be called "extreme gearing"