I always use a topstitch Schmetz needle (bigger eye), topstitch has a deeper longer groove also so there is less friction on the needle. At superiorthreads.com you can get educated on needles and thread. I haven't sewn with CT threads yet. But I do have a spool I bought with a quilt project. There can be bad spools of thread, I learned that from Bob the Thread Guy at superior threads.
Diane/Wyoming