You state that these are
New tubes? I assume the old tubes were automotive/Schrader type valves?
IF the old tubes were using Schrader valves, BE Aware that the holes drilled into your wheel rims are
oversized for presta/french valve stems. The oversize holes
will cause a non- repairable puncture next to the presta valve stem. This can be prevented by installing a schrader to presta shim (a thin metal or plastic collared -not flat- washer inside the rims valve hole.
I have also had excellent results using 1/4 inch rubber grommets from Radio Shack or Hardware store.