stroker motor
If you warrior is running good leave it alone. I have a lot of experience on stroker big bore warrior motors and I do all my machine work, the +4 hot rod crank big bore kit is pretty reliable but its only giving you 10% more displacement 380cc = 10% more power. now if you have a project build with a bad crank go for it, I just built a hot rods +4mm/68.5mm crank with a +4mm/87mm piston = 410cc +1mm intake valve running about 10.7-1 compression very nice setup, runs very good 4000-8000rpm powerband, the problems I had in the past with big bores are #1heat, air cooled motors and anything over 10-1 compression and you need octane boosters so stay under 10.5-1, #2 racing on the street on my bigger bored 88.5mm +4 stroker motor with 11.5-1 compression motor I cracked the right side crank bearing housing case so thats your weak link and has to be strengthened, so on these bigger motors stay on the dirt and you'll be ok, my next build is to strengthen the cases, a 90.25mm piston with +4mm crank=440cc, +2mm/42mm intake valve, 10.5-1 compression, milder cam to lower powerband 3000-7000rpm, so ill see what breaks this time.
