Re: 15 mile round trip too much for new build?
Ditto: You don't want to abuse the engine but there's no need to baby it either. Let it wind out a few times but just don't hold it there for too long. 15 to 20 second bursts will suffice alternating with some half throttle cruising. Your engine will love you for it.
But as Joe said; check the critical things for tightness, especially fenders if you have them. Engine mounts, intake and exhaust manifolds, (don't over tighten them) axle nuts, steering gear etc. You'll be good.
Report back and let us know how your first solo cruise went.
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