Hi dickiebould,
I've looked at the indexes for the 1871, 1881, 1891 and 1901 Censuses for Namans in Yorkshire and none are recorded in the first three of those and just four in 1901, none of which is in Leeds.
Do you have any further information which might assist a look-up i.e. place of birth, other members of family, etc.?
I'll be pleased to have another go if furnished with more ammunition.
Regards,
lancs.fox