Second Blown Gasket??

[Skeldaw]

Hello guys, My 400ex had the mid engine gasket blown, So I had it fixed by a shop and it runned fine for few months, Now I just noticed that my head gasket is leaking?! I had that one changed too so it's almost brand new... What can cause that? When I bought this quad the guy told me that it never been open before but the guy from the shop told me that my EX is a 402... ( So the engine already been open )
What can cause that? Is my engine not stock so ? Is the top engine bolt are loose?
Help!

[exvetrider]

The head studs are pulling.You need heavy studs studs from GT Thunder.

[Skeldaw]

Originally posted by exvetrider
The head studs are pulling.You need heavy studs studs from GT Thunder.
I thought this only happen to 440ex? And don't the guy of the shop would have seen it?

[CJM]

If the quad isnt jetted right the heat will pull the studs out. Or if you overtorque them.

Also if the surfaces of the head or jug arent flat (warped) can blow gasket as well.

There is too little unknown here to determine why it blew. Could be cheap gaskets as well.

[Skeldaw]

Well it's not the same gasket that blown the last time, And I ride in winter does it have something to do? ( I still ride at -20 celcus ) But I never saw i sign of overheating and im running motul 10-50 5100 ( That's what the dealer told me to run )