race fuel cap?

hi i wonder if someone can answer a question. i brought a race fuel cap of another member just to stream line the bike abit. i noticed there is no pressure relief in the new cap, is this going to cause me a issue. like blowing up?

 

The race caps usually have a small ball bearing valve on the rim somewhere.

 

this cap is just a cheap Chinese one, defo no pressure relief that i can see.

 

I've been running the same cap (£15 Chinese one) for years with no issues on my trackbike.

 

cheers buddy