I just fitted a new chainset to an old frame i'm using for a singlespeed buildup. The bottom bracket was supplied together with the chainset and the chain is in the correct line, but there is a large gap between the left crank and the frame, see pic.
The frame across the bottom bracket is 68mm.
I have also taken a pic of the gap between the pedal end of crank and the chainstay.
Is the gap correct??

Is it tightened down properly?

is the left crank arm torqued down properly?

edit: beat me to the punch...

Yes tightened down.

Its tightened down, no way it will go on any further, and if i take the screw out, i can see that the square hole in the crank is about 5mm short of the end of the bottom bracket spindle. It seems as though the square on the crank does not match the size of the spindle square.
I thought they were a std size.

Looks like i've got an ISO crank on a JIS spindle.
https://sheldonbrown.com/bbtaper.html

Do you have the same gap on the drive side?

Yes, it does indeed look like an ISO/JIS mismatch, but a harmless one since a) chain line is good, b) cranks don't bottom out on spindle, and c) crank arms don't hit chainstays. Don't worry about it.

Yes same on the other side

Ride your bike.

You're good. Don't worry about it.

If Scrodzilla says "Ride your bike" i'm ok.

That was Morgan. And I wouldn't listen to anything that crazy mofo had to say.

What crankset is that? It looks like it's made of forged steel.

I'm crazy.

I'm confused. Who is Morgan and who is crazy??

Its steel, cheap, and the first thing i'll be changing.

In that case, I very highly doubt it's ISO.

Are we gonna do this again?

Morgan so craycray.