(Spark?) Knock on cold start idle
 

I searched around a bit and found that a little bit of knocking or stumbling is actually common for a cold start. I am running e85 on the OFT tune for a stock fuel system. Ordinarily I wouldn't be concerned since this issue is common and it goes away within a couple minutes of idling. However, with the different fuel I am wondering if there is a higher risk of something breaking.

What do you guys think?