I can't seem to find a tire guide anywhere if there is one. I bought my SE with aftermarker 20's on them. I'm trying to find the recommended tire pressure for these 20" tires, but can't seem to anywhere. All I know is on the tires it says 51 p.s.i. max. They are currently around 41 p.s.i.But I'd like to know the recommended amount. Does anyone happen to know or where I can find a guide? Thanks