I've had one good ride out if my Grubee skyhawk GT5 since finishing the build on Sunday. Yesterday I go to get another ride out of it but I tighten up the exhaust bolts first. Jim, at pedalchopper.com let me know to tighten them up after the first few rides.
Anyway I'm tightening the bolts and notice one bolt isn't locking. Long story short I back it out and shine a light into the hole and its nearly threadless.
Afterwork today I'll be getting a tap&die set and getting it back to running.