Anybody run an imperfect chainline for hundreds of miles or more on their SS or fixed gear? How far from dead straight can a chainline be before you run the risk of throwing a chain?

I highly doubt any of my bikes have a 100% straight chainline and iv never thrown a chain, even running chains that smile at me.

I generally adjust them until they're straight enough that I can't see a bend. But I've never actually measured. It doesn't take that much work, and you only have to do it once unless you're changing stuff.

For a while my chain line was imperfect and I did end up trowing my chain. But my rear cog is also 3/32 and my chain is 1/8. The combination of variables = chain throwing and crash. I have since straightened my chain line and eliminated this problem.

my Peugeot has a pretty bad chain line. It is mostly straight but I can tell that it is no where near perfect. I have been riding it for about 1.5 years. No problems.

I ran a SS with a chainline that was 4+mm off with a magic gear. Never came off but was a little noisy.

Okay, thanks for the replies y'all.

It is worthy of note that 3/32" chains are more tolerant of lateral flexing than 1/8".

you are correct,since 3/32" chains are made for deraileur applications.

Finished the build and test rode it today. I thought my BB axle was going to be too wide, but my concerns were unfounded as the chainline is straight and quiet. Thanks again for the replies.

The chainlines for my various fixed gear bikes have never been perfect, most with noisy riding. For years I ride on the same chains and never threw even one. I keep them lubed regularly, and that minimizes frictions from a slightly deviated chainline. If you want to have a sense of security, just change your chain once a year. Really, for just a few dollars, it's probably not a bad idea.