My First build. Done finally. Some nice upgrades

[FurryOnTheInside]

That bike is sweet I want that chain and tensioner bc I'm always breaking chains or snapping links I carry a bookbag full of tools and the chain breaker kit so I can use the regular chain links as a master when it happens and an extra chain.. Is that #41 chain the same size as the 415 they sell us on the motorized bike sights?And would the master link from the 41 chain fit the 415 chain?

#41 is roller chain, for garage doors and perhaps some tractor applications. It is 1/4" wide (internal width) which is not the same as #415 moped chain (3/16"). It's twice the width and nearly twice the mass of #410 BMX chain (1/8") which I find to be perfectly adequate.
My next chain will be even thinner than that (3/32"), even lighter too!
Lighter chain is easier to control, and it is easier to clear the stays without needing the tensioner to lift/deflect it very far. Lighter chain uses up less power, so more power gets to the tyre.