Cyber Sale

Load image into Gallery viewer, Hop Up Kit, 420 Predator OHV &amp; 13/15hp Clone, Stage 4

Cyber Sale

Speed Kit, 420 Predator or OHV & 13/15hp Clone, Stage 4

$936.00
$1,200.00

Speed Kit Selection Guide
This kit is similar to our Stage 3, but adds a ported and milled head with stainless valves, a stud kit, and heavy duty valve train components. Allows up to 35+ HP out of a 420 engine.

This kit is for OHV engines and will not fit Hemis.

Kit Includes:

Fully Ported and Milled Race Head (Genuine Honda Core)
High-Torque Genuine Honda Core (The Best!!)
High-Flow 36mm / 31mm Valves with Lash Caps
Dual Springs with Titanium Retainers
307 Race Cam
Black Venom Aluminum Roller Rockers
Valve Cover Spacer
Chrome Moly Pushrods
Choice of Carbs (Or use your own)
90mm Forged Flat-Top Piston with Rings
Billet Rod (+.040" Longer)
Offset Timing Key
Carb, Insulator, Head, and Case Gaskets
ARP Bolt Kit

*Note: This kit only fits 414 & 420cc (90mm) non-hemi engines. Filter should be sprayed with K&N type oil, especially in dirt applications. Oil not included. Billet aluminum flywheel REQUIRED. These kits are intended for experienced engine builders. Some clearance, fitment, or other engine building "tricks" may be needed. Picture for reference only. See above description for actual content.

Due to the head work required for this kit, please allow 1 week to ship.

FAQ Accordion with Animation

Frequently Asked Questions

When will my order be shipped and how long does delivery take?

Orders containing in-stock items typically ship within 3–5 business days. Orders that include assembly will require 7–10 business days to prepare. Please note that during the holiday season (Thanksgiving through Christmas), processing times may be longer due to high order volume. Once your order has shipped, you’ll receive an email with tracking information. Most orders are shipped via Less Than Truckload (LTL) freight and generally arrive within 3–7 business days. Deliveries to remote areas (such as mountains, forests, valleys, or islands) may take longer. You can check the estimated delivery date on the carrier’s website using the tracking number we provide.

How your vehicle is shipped?

Unless otherwise noted, the vehicles we offer are shipped crated or on a pallet and do not come assembled unless you’ve selected our assembly service. Assembly typically requires a few basic tools and mechanical knowledge. If you're not confident in your ability to safely assemble a high-speed off-road vehicle, we strongly recommend selecting professional assembly or having it assembled by a local mechanic.

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Do you offer financing?

Yes. Buy-now-pay-later financing is available with our preferred partner, BreadPay® (please see their icon under product pricing for details).

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How can I get assistance if I have question on products?

Please call 888-886-5846 and talk to one of our knowledgeable sales representatives between 9am-3pm PST. Or send us email at orders@gokartsusa.biz.

What warranty is included with my purchase?

You're covered with confidence at GoKarts USA®. Your satisfaction is our top priority. Every purchase comes with manufacturer-backed warranty protection—including up to 12 months of engine coverage—to keep your ride running strong. TrailMaster products also include a 6-month parts warranty for added peace of mind.

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What does 95% or 98% Assembly Mean? What do I need to assemble if shipped in crate?

For shipping safety, most vehicles cannot be fully assembled prior to delivery.

Minor assembly is required—this typically includes installing mirrors, connecting the battery, adjusting handlebars, and other small components. Before operation, please ensure all screws and fasteners are tightened, engine fluids are at proper levels, and the battery is fully charged. Your factory warranty remains valid right out of the box.

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Speed Kit, 420 Predator or OHV & 13/15hp Clone, Stage 4

Frequently Asked Questions

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