My chain makes noise too. I thought it was rubbing on the chainguard - it is not.
I think it is because the chain alignment is off between the chainring and rear cog.
I have been meaning to try taking a washer and putting it on the crank to kick out the chainring a bit but have not had time.
Got the noisy chain virus myself.
You will find a cure - not sure that red grease is the answer though.
And yes - pictures help.
can't fix it if we don't know what has happened, what the noise is like and when it happens.
gotta know the history and see the parts to determine what the cause of the problem is before a solution is suggested.
what does the noise sound like?
does it happen when the bike is pedaled gently in a workstand or not?
does it happen when pressure is applied to the pedals while riding?
chains and cogs wear together.
a very worn drivetrain will get you down the road well-past it's "acceptable" wear point, not making any noise and not "skipping" if the rider doesn't put enough pressure on the pedals. BUT! change the cog or chain and then there's trouble:
The good news is that that cog will likely work for your bike - but it needs some modification.
The picture with the red bike frame is from an old New Departure Model D.The profile is not the same as the ichibike cog so it will need grinded down to more closely match the shape of the old cog - especially the teeth.
All the other pictures are from an Ichibike cog that I had used previously. Like you I i went and bought one of these to convert a modern coaster brake wheel to skiptooth. A local friend of mine @Mr. Monkeyarms let me know before the cog was even mounted that the teeth needed grinded down prior to using otherwise it could chew up the chain. If you feel the edges of the teeth on your cog you will notice that there is a pretty hard-line edge. This will need grinded down a bit in a few areas - you can use a hand-held file with the cog in a vise just tightened enough to hold it in place. Note that the areas that are lighter on the edges of my cog are where it was grinded.
The teeth on my cog seem to be grinded on all 4 sides of each tooth not quite to a point though - note the tooth in the center of the second picture. Not too much but not too little.
The edges of the gaps between the tooth were also very slightly rounded off.