If it's steel you should be ok to re-size it, Aluminium, not so much.
Have a read of this article on your options. https://www.sheldonbrown.com/frame-spacing.html
@Bernhard started
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If it's steel you should be ok to re-size it, Aluminium, not so much.
Have a read of this article on your options.
https://www.sheldonbrown.com/frame-spacing.html