CBR600 F3 Exhaust Blowing at front
 

I bought this bike a few months ago and (where the pipes meet the cylinder head) I've had the studs tightened up three times and the gaskets replaced once (plus they also cleaned the threads out etc.

For some strange reason, the studs keep loosening off.

The longest it's lasted without loosening off too much was after having the gaskets replaced (two months). However, they weren't genuine Honda gaskets and so the bike shop reckons this is the next thing to try.

The pipes are stainless steel ones.

Has anyone else had this same problem? Any more ideas?

As long as the exhaust is in good shape where it goes against the engine, new gaskets should last a while. Of course as long as the bolt/nuts dont come loose. What I would do is stop paying a bike shop to do something as simple as replacing exhaust gaskets. And with new gaskets, a little high temp RTV on the gaskets, maybe some blue thread locker on the studs and nuts AND the rear/muffler is bolted to the frame properly so as not to cause a levering affect on the new gaskets. AND properly torqued nuts/bolt/stud thingys. I believe one of the keys for exhaust gaskets NOT leaking is to NOT over tighten the bolt/nuts, kind of like an oil pan gasket on a car engine.