Short article on chain tensile strength.
http://sidewindersprockets.com/tensile.html
It isn't rocket science.
428 chain tensile strength and common prices
0-ring
5300 $69
5340 $79
7000 $100
open
3970 $16
4000 $16
4200 $30
5060 $51
5280 $34
5500 $34
5840 $45
There are only two reasons to run an open chain. The first is to prevent a tiny bit of parasitic power loss. The second is some people simply enjoy mucking around in solvents and hot oils.
The parasitic loss of rings is so tiny most riders wouldn't be able to tell the difference. If you're competing or hyper-miling, by all means, a well-maintained open chain is the way to go. Of course, this assumes the open chain is perfectly maintained at all times. It doesn't take much neglect for the pins and rollers to dry out, water to intrude into the chain and causing corrosion, and/or metal-to-metal contact between the plates to create significant parasitic drag exceeding that of rings by quite a bit.
Of course, there are those who go zen-like when maintaining their motorcycles. By all means, those folks should have open chains. Back in the olden days when all chains were open I'd always buy 2 chains--one to be used while the other was being maintained. Super easy to swap chains simply by hooking one to each pin of the master link--pulling the chain off the bike pulled the other chain on the bike at the same time. Hook up the master link and go. That eliminated the most anti-zen chore of feeding the replacement chain over the countershaft sprocket. Swapping chains often kept both and the sprockets wearing evenly. With two chains the bike was never down for chain maintenance and I never had to rush the solvent bath/drip dry/heated oil soak/drain maintenance process, an attribute of the maintenance program that prevents the need to get the bike bike on the road quickly from mucking up the mental state pursued in doing the maintenance in the first place.
Maybe these zensters should by a Harley and a variety of soaps, buckets, cleaners, polishes, waxes, rags, towels, dusters, applicators. It should be an old Harley, with a chain. An open chain. Then they'll never have to ride at all! They can forever wash, clean, wax, dust, polish, and dabble in solvents and hot oil and drink beer to their hearts' content.
Cheap chains are a false economy because when they wear they ruin the sprockets. By the time you factor in 4 times the sprockets and gaskets and oil, you've spent ~3 times has much as if you would have spent the extra $20 for a good chain in the first place. Worse, folks often sell the bike rather than deal with the hassles of replacing the chain and sprockets. This is especially true if one takes the bike to a dealer for replacement. I couldn't afford to ride at all if I had to pay a dealer for repairs and maintence. One rarely finds a used TW with more than a few thousand miles on it with decent chains and srpockets. Hmmmm?
A well-maintained open chain will last just as long as an o-ring chain of equal tensile strength. A squirt of lube every ride isn't "well-maintained", but it certainly helps an open chain. A squirt of lube may be all the maintenance a chain gets while on a trip, though, but as soon as possible after a trip an open chain should be treated to the full maintenance procedure. All this maintenance costs money. Even if your time is worth nothing because you're a total bum, the money is still a factor, especially if you're a total bum who doesn't have any.
O-ring chains thrive on neglect. All that is necessary is enough lube to keep them from rusting. An occasional squirt of lube is all the maintenance an o-ring chain needs. Subject a cheap open chain and sprockets to the necessary maintenance an o-ring chain requires, which is pretty much what most riders do, and the o-ring set will easily last 6-8 times as long as the cheap open set. If you ride a lot, the o-ring set will save $250-300 of the life of the chain simply in replacement costs.
