????? The 428 should be more than sufficient. What brand and type chain are you running? We ran nothing but the RK Gold 428 on our kasea and never had any abnormal issues. You do need to run a steel rear sprocket if your not already. The aluminum ones don't last which in turn will wear out your chain. But as far as the 428 not holding up on the track we run a 420 setup on our cobra.
Brandon Waltz #11
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