My bravo has worked fine until recently. It suddenly stopped running and now it won't start again. Fuel and spark is checked, i haven't checked compression however i notice now that when im trying to run start it, the rear wheel skips and i have to put pressure on the rear wheel otherwise it just skips and won't turn over the engine. The clutch is newer and im sure its not that. Could it be something about compression or maybe clogged exhaust port?