Mower filters are smaller than the CV2 used on most British bike filter mounts.
The Kawasaki & Kohlers are thinner but the Short Tecumseh is he shortest I have on the shelf
Most are of course NP threads
You might find this link helpful Stens oil filters
Stens filters are made by Champion who are the OEM makers for all of the USA made engines that have not gone to Chinese ones .
All are more then good enough for motorcycle use and really cheap, particularly if you can find a mom & pop mower shop who will order the 12 pack for you
If your maching skills are limited then all of the engine makers do an oil cooler take off extension that fits over the original oil filter housing which can easily be modified to fit on a bike with some imagination.