Right size tube for tyre

Hi
Does tube and trye size really matter? would it be ok to fit a 1.5 innertube to a 1.75 mtb road trye? I would be using presta valves and using them at around 80/90psi. Any views would be appreciated, thanks.

It's Ok to use the 1.5" tube. Tubes can be somewhat smaller than or equal to the tire size, but not larger than the tire size.

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"There is alot of blather here that does not float the hooey barge." boudreaux 11/22/2005

Thanks mate.