Dick, it depends on WHICH bearing is holding that crankshaft from moving forward. It DOES have to be held from moving around, right? the front, or #1 bearing, in most of these engines, is the one with the tightest fit on the crank, and takes the majority of axial and linear loads, so it should never become "loose" or have the crankshaft moving fore-aft in any great way.

One thing to remember, as well, 3W sets their engines up pretty well, and I'm sure the bearings are installed with the consideration for about .001" or so of fore-aft crankcase growth as the engine heats up. Plus, 3W uses sealed bearings not ones with loose races that allow the crankshaft to effectively "float" on them.

One thing I learned a LONG time ago, with ball bearings, it does not matter how much "float" you have in a static non-running environment, what matters is how true and drag-free the bearing runs under load. Too much "float" can actually cost you power and cause premature wear. If 3W designed their engines a certain wayu, deviating from taht would probably not be the best idea. In this case. . the crank is moving. 3W did NOT design it that way.

Think I'll stay awake for a while. You should try the same