I have had a east coast Atv clutch with stock inner and outer hubs 3 stock springs 3 heavy duty springs and NO lock up and have beat the hell out of the clutch for the past 2 years earlier this year tire it down it still looked brand new..I don't do a lot if riding in pavement but I can tell you with knobbies it won't hook up in any gear even with my 320lbs on it my quad hooks harder with the paddles in the coal most if the time!!
I have launched my quad hundreds of times in second for hill climbs and a shit load of times in 3rd racing and clutch it on hills whenever needed, I hope you get your issue fixed if not call east coast they use te clutch in all there drag bikes with slicks and alot don't have a lock up!!