ADA Racing Yamaha 701 Cylinder Head Kit

The ADA Racing Billet Heads for the Yamaha 701 are made from 6061-T6 aluminum and CNC-machined for consistency and performance. This head uses the stock head bolts and is clear anodized for protection against corrosion and features dual water outlets for additional cooling. The head shell includes o-rings that fit into the grooves in the head shell and brass fittings. Head shells are available in standard or girdled versions for those running higher compression and looking for extra insurance. The girdled version requires the girdled hardware kit sold separately. Multiple dome configurations are available to tailor to your specific engine needs. Two domes are included with this kit; additional and replacement domes are available separately. 

NOTE: ADA Racing optional pipe bracket available for exhaust systems that mounts to the head like the stock 3-bolt exhaust. 

ADA YAMAHA 81MM BORE DOMES
Billet dome has .005” squish relief at 82.5mm (fits up to 83mm piston) with a 4˚ angle.

YA2137L - 37cc 170lbs/91 Octane
YA2135L - 35cc 185lbs/91 Octane
YA2134L - 34cc 192lbs/95 Octane
YA2133L - 33cc 200lbs/100 Octane
YA2131L - 31cc 215lbs/110 Octane
YA2129L - 29cc 230lbs/115 Octane

NOTE: 35cc Dome for 100 Octane with Dry Pipe

Ships via UPS or USPS Priority.  All "Open Box" items are excluded from our free shipping offer and are not returnable.

International Customers: Shipping charges reflect transportation costs only and do not include international brokerage fees, duties, GST/HST/PST, or other applicable taxes. Customers outside the United States may receive a separate invoice directly from the carrier for these additional charges.

If your order arrives damaged or appears defective, please submit a claim through our Customer Service Order Damage Form. Our team will review your submission and contact you within 24 hours (excluding weekends and holidays). All damage/defect claims must be reported within 48 hours of delivery.

An RMA# (Return Merchandise Authorization Number) is required for all returns.

Returns must be initiated through your Customer Account Portal within 10 days of delivery.

Returned items must be:

• Unused
• Uninstalled
• Unmodified
• Complete with all original packaging, hardware, manuals, and accessories

Returns not related to damage, defect, or an Atlantic Jet Sports shipping error are subject to a 20% restocking fee. Customers are responsible for return shipping costs.

Unauthorized returns will be refused at our shipping dock.

[View Full Return Policy & Return Instructions]

Non‑Returnable Items

The following items are final sale and not eligible for return, exchange, or store credit:

• Seat Covers
• Mat Kits, Mat Sheets
• Chin Pads
• Waterboxes
• Aqua Cart & Factory Zero Transportation/Beach Dollies, Totes, Display Carts, and all related Parts/Accessories
• Watercraft Stands
• Aqua Performance Watercraft Steps
• RRP Handlepoles
• Special Order Items
• Close‑Out Items

Electrical Components (non‑returnable):
Starter Motors, Regulators, Relays, CDI Units, Ignition Coils, Stator Coils, Stator Assemblies, Fuel Injectors.

All warranties are those of the manufacturer and not Atlantic Jet Sports. We will be happy to assist you in filing a warranty claim with the manufacturer, but please remember that the manufacturer determines whether a claim is approved or denied. Any modification to a product voids your warranty. All claims for consequential, physical, incidental, or special damage are hereby excluded.

Performance Product Use & Compliance Notice

Atlantic Jet Sports supplies high‑performance components engineered solely for closed‑course racing and sanctioned competition. These parts are not designed, tested, certified, or warranted for use on public waterways or on watercraft equipped with emissions‑controlled systems.

Installing or using these components may change the watercraft’s safety characteristics, emissions compliance, or legal classification. Using competition‑only products on public waterways may violate federal, state, or local regulations.

By purchasing, installing, or operating a watercraft equipped with these components, the user acknowledges and accepts full responsibility for all associated risks—including, but not limited to, personal injury, property damage, mechanical failure, or legal consequences. The user further agrees that Atlantic Jet Sports assumes no liability for damages arising from improper installation, misuse, or operation outside of competition environments.

For best performance and safety, Atlantic Jet Sports strongly recommends installation by a qualified technician experienced with high‑performance Personal Watercraft systems.

Product Installation Disclaimer

⚠️ Warning — Professional Installation Required

• Ensure the hull is fully ventilated and free of fuel vapors before using electric or battery‑powered tools. Failure to do so may result in fire, explosion, serious injury, or death.
• Disconnect the battery before performing any installation or maintenance to prevent accidental ignition, electrical shock, or unintended engine engagement.
• Allow the engine, exhaust, and surrounding components to cool completely before beginning work.
• No smoking, open flames, or spark‑producing devices should be present during installation.

This product is not intended for use on watercraft equipped with pollution‑control systems. Modifying or removing emissions‑related components may violate state or local laws and may render the watercraft illegal for use outside of competition.