Did you put the idler in the right way round?
I've had 5 sessions with mine now, about 10 packs, and everything has bedded in a lot.
I to was initially concerned about the tightness of the drive train but it does say in the book about it bedding in and re tensioning the belt after in so I made sure I was happy it was built right, ran a pack or two checking for binding and it has all loosened and is now a lot more free.
Its possible to put the front clicker together incorrectly, for a slipper pad to slip out the spur while assembling, the clicker nut will undo after 3 or 4 packs, loctite it, the diff sun gears may need another shim or two, use shock limiters above the spring cradle to limit shock travel so the drive shafts don't catch on the outdrives when you press the suspension all the way(best done with springs off but spring cradle on, especially necessary if you don't fit the boots), the belt will loosen, the slipper will need double checking, front blue or yellow springs work well on the rear and I think thats it.
Have fun, I put a few packs through mine today and the biggest issue was to much drag brake which was set low but the SC411 Tenshock motor is very strong and it was like putting a handbrake on as I lifted off for corners so I spun. I've also put 100grams of weight under the saddle packs which helped.
