I'm trying install a new GXP bottom bracket for some Sram Omniums, and when coming to thread in the non drive side cup no matter what I do it seems to want to thread in at an angle and I'm met with considerable resistance, where as the drive side cup is threading in without any hassle. I haven't tried to push it any further in fear of stripping the shell. Can anybody help me out?

Too bad we can't reach through the interweb and hold that cup for you.

Do you still have the original cup and does it thread in well? Can you visually inspect the threads for any damage? Have you tried to rotate the cup backwards initially to capture the first thread before rotating the cup in the right direction to thread it in? Andy.

Perhaps the drive side cup is keeping it from getting started properly. Try removing the drive side cup and getting the NDS cup started before reinserting it. Tighten the DS cup fully then finish installing the NDS cup.

The original cup threads in perfectly, doesn't seem to be any visual damage to the threads at all. Everything's cleaned and degreased thoroughly before installation, It's catching the first thread and after about two or three turns it just doesn't seem to want to thread in any further.