Predator 420 build for BAJA Warrior!!!


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So I’m wanting to build a 420 predator for a Baja mini bike. It’s brand new I’ve already put a stage 1 kit on it but it hasn’t been mounted to anything. I’m looking to have it get up to 70+ mph on a flat surface. It will be solely for street riding, I want to build it right but I’m on a budget. I was already thinking of going stage 3 kit w/mikuni carb, no idea as far as clutch chain and sprocket setup. Will I need to have anything bored or what. Any fabrication tips would help I’ve seen the few builds on YouTube only


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Phoenix, Arizona, United States
Well, not to ruin you're fun but you will need at least a 40 series torque converter, which is about $360. The reason being is this engine is so incredibly torquey that is will literally melt centrifugal clutches. So it's either a 40 series or a chungus-sized jackshaft.

Anyways let's talk about mods! What you'll want to reach 70+mph is to remove the governer, install a billet connecting rod, better valve springs, and a billet flywheel. But for now, you can port your head, get a bigger carb, and install a pulstar sparkplug. After these upgrades consider a better cam, pushrods, and turbo, or supercharger. Now into the crazy high-end mods check out paul's karts online store for the best racing engine heads and piston heads, In addition, you can add a DIY propane booster in the carb just find a way to get propane into the carb (propane burns like well-mixed nitrous in an engine except you don't have to worry about fuel, air, nitrous mixes). NOW if you do all of this your engine will overheat FAST so you'll have to install an oil pump and radiator, along with a battery.

So at the end of the day this thing will crank about 7k to 8k RPMs @ 40 horses resulting in a 100+MPH mini bike
Enjoy your build!
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