Darth Lefty 

I've got a daily commuter bike with

• aluminum 38t narrow wide front ring, Race Face Ride
• steel 17t single speed freehub conversion cog, unbranded
• 11s chain, KMC Z1 Anti-Rust

Approaching 2 years and probably >1000 miles and wondering what to expect for drivetrain wear. The chain line isn't dead nuts as it's got 17-18t rear cogs and the perfect line is the space between them. The individual parts are not fancy... ie, the conversion cog is not the Surly stainless one for example. I typically replace derailleur chains due to damage (like from FD drop) and don't get the full service life, not expecting that here!

QBP has been selling bikes arranged sort of like this the last few years, on models that could be converted to derailleur. My Stormchaser but also the Nature Boy, Super Professional, Timberjack, Lowside, and a few years ago a Karate Monkey.

veganbikes

I would use a chain checker and see, probably could go for a while. SS stuff doesn't wear the same as gear-ed bikes. If you start to hear more noise or it is getting sloppy replace it and maybe just have stuff on hand, if you know you want the Surly cog or something different (Wolf Tooth?, Profile Racing?...) go for it. Typically nicer components will be quieter and may last longer but are typically in better round with better tooth profiles and such. But hey as long as things don't look exceptionally worn or damaged and the chain checker shows ok (with a clean non-gunky chain) you are good to go.

Dylansbob 

As long as you've kept up on cleaning and lube, it'll last as long as any other SS drivetrain. Any difference between 1/8th and 3/32nd is negligible and that's not enough deflection to prematurely wear out the chain laterally.

Rolla

I like a perfect chainline as much as the next guy, but a couple of millimeters isn't a big deal and shouldn't accelerate wear appreciably. Keep riding as is and you'll eventually find out how long the parts last! Chains are relatively cheap; measure and replace it when warranted to extend the life of the cog and chainring.

TugaDude

Unless it is severe, I wouldn't worry too much about the chain line not being perfect. Especially with 3/32" chain, there is a lot of flexibility and I don't think it will end up being a problem.

c_m_shooter

I change the chain before it wears out, they are cheap and it makes the cogs last forever. By the time you can measure any wear in the chain, the cogs are done. If you are only putting 1k per year I would change it every 2 years, unless you ride in the rain a lot.