A ticking problem on start up.

Depends on where thie ticking is coming from. It could be lots of things, lifter ticking warn rocker piviot, piston clearence too loose, wrist pin noise, timing gear chatter, exhaust leak....etc. where is the nosie coming from?

yes chevys 3.4 and 3.5 have common lifter noise, have you checked the oil level. I would a better oil ,and I put lucas oil treat in my customers cars after oil changes

It does sound like a valve lifter problem to me also. It should be covered under warranty. It's a mechanical failure of a component of the drivetrain. Ask them to show you the specific exclusion if they say it's not a warranty problem.Powertrain warranty is 60 months/60,000 miles ( which ever comes first).

From what I recall, they are accessed by removing the seat.

Take off the Pillion seat to reveal the nut for the driver's seat. Remove this and then you should have exposed the coils (amongst other things).

Or could be lifters ticking. Try using a heavier oil and see if that helps.

u can set it lesser or more to help cease the sputter but it needs a pro ajust or cleanin--u may be able to doit urself-ther are books

lift rear end ensure wheel is straight, chain will tick if not running true. next step remove chain and turn wheel by hand, listen for noise, wheel should spin freely when spun, like once or twice around before it stops. sometimes also ticking sound from drum brake is just a loose lever from the brake pedal to drum. pads will not tick. to be really safe, remove wheel and take apart.