Singlespeed & Fixed Gear - Mercier Kilo WT - my chainline seems off...

A couple weeks back I received my kilo wt and for the most part it seems solid. One thing in particular is driving me nuts though...

I am getting a "ping" noise coming from the drivetrain.

I am 100% certain it is not the bottom bracket.

If I simple push the bike backwards I get this little ping noise ~2 times per crank revolution. I can also hear the noise when riding on the road.

These fixed gear/ss bikes are so simple, really the only thing that could be the problem is the chainline.

The bike comes with a sugino 48T crankset. Not sure the exact model. Any idea what length BB spindle I need to get my chain straight?

is everything properly tightened, BB, crank, hubs, ect...

Try loosening your chain.

Also, the bikes come partially assembled, the cog/lockring are not tightened and every nut/bold/adjustment should be checked before riding.

Yep, I manually checked every bolt myself.

Also I'm using the freewheel not the cog/lockring.

I suppose I'll try loosening the chain and see if that makes a difference.

I had chainline problems with my Kilo WT, and had to move the cog outboard about 3mm by respacing the hub axle and redishing the rim. Problem was that the dropout spacing was off and the left and right stays were not the same distance from the centerline of the frame. Also, the Sugino RD2 crank was not set fully on the spindle, and moved inward a bit after multiple retightenings to the proper torque (33 ft-lbs). Another problem is that the stock cog is a total pos and does not run concentric or mesh properly with the chain, so getting consistent chain tension is nearly impossible. I replaced it and now it runs smooth and silent with a Soma 19T x 1/8 cog.