If you have horizontal drop outs like you get on road frames from the 70/80s then it shouldn't be a problem, plenty of people have done it. Check out Sheldon Brown for tips and tricks and check out these guys.
@Bernhard started
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If you have horizontal drop outs like you get on road frames from the 70/80s then it shouldn't be a problem, plenty of people have done it. Check out Sheldon Brown for tips and tricks and check out these guys.