GasGas MC 85 Engine Packages
Transparent GasGas MC 85 mod packages from HP Race Development: Weekend Racer, Privateer, and Factory Works builds with race porting, GET CDI mapping, billet head options, and complete engine services.
Select Your Level
Choose the package first. The engineering notes and build justification follow below for families who want the deeper breakdown.
MC 85 Platform
85cc PlatformWeekend Racer
Competes head-to-head with national mod kits without the fluff or unneeded extras.
$650 starting
Pricing may vary based on condition of parts received.
What You Ship Us
Cylinder with powervalve and carb
Includes
- Race Porting
- Carb Bore & Setup
- Head available as an add-on
- Piston & Gasket Kit available upon request
Recommended For
Local racing, practice bikes, and families who want real GasGas MC 85 performance without overbuying.
Pricing may vary based on condition of parts received.
Privateer
Our most popular GasGas MC 85 upgrade: the full synergistic port, ignition, carb, and head system.
$1,850
Pricing may vary based on condition of parts received.
What You Ship Us
Cylinder with powervalve and carb
Includes
- HP Race Porting Spec
- HP Custom Mapped GET CDI
- Carb Bored & Set Up with Notes
- Billet Head with HP Custom Race Dome
- Piston Kit
- Top End Gasket Kit
Available Add-ons
- +Professional installation onto customer's engine: +$150
Recommended For
Regional championships, serious amateur racing, and the best value GasGas MC 85 mod package.
Pricing may vary based on condition of parts received.
Factory Works
Zero compromises: complete top and bottom end build, professionally assembled and verified.
$3,950 / $4,600 with dyno
Pricing may vary based on condition of parts received.
What You Ship Us
Complete engine
Includes
- Factory Works Porting
- Custom HP Mapped GET CDI
- Carb Bored & Set Up with Notes
- Billet Head with HP Custom Race Dome
- Piston Kit
- Top End Gasket Kit
- Billet Connecting Rod
- REM / Super Finished Internals
- Ceramic Bearings for durability and reliability
- Cerakoted Cases available upon request
- Dyno Test & Power Verification available: +$650
Available Add-ons
- +Vapor Blast & Inspect Engine Parts for used engines: +$250
- +Replace all wear parts: priced after inspection
Recommended For
Loretta Lynn's, Mini Os, national-level GasGas MC 85 and Supermini programs.
New engine pricing shown. Used engine costs extra after inspection.
The Stock Bottleneck
"A bolt-on MC 85 mod list can make noise and peak RPM, but it often misses the matched setup that makes the bike drive out of turns."
The HP Race Dev Solution
"We match the MC 85 cylinder, powervalve, GET CDI map, carb bore, and head spec so the package works as a complete race engine."
We don't just "grind ports." We mathematically correct the engine's geometry to solve this specific flaw.
Engineering the MC 85 Platform
The GasGas MC 85 responds best when the package is developed around the whole airflow and combustion system. Porting alone can shift the power curve, but carb signal and ignition timing decide whether that power is actually usable by a young rider.
The Privateer package gives the MC 85 the full synergistic system: HP Race porting, custom mapped GET CDI, bored carb setup notes, billet head, piston kit, and top-end gaskets. It is built to be the best-value race upgrade, not a random pile of parts.
Factory Works MC 85 builds add complete-engine prep and durability: billet rod, REM finished internals, ceramic bearings, optional Cerakoted cases, and dyno verification when selected. That is the route for national-level mini and Supermini programs.
Parts For This Platform
Common products used with MC 85 package builds.
GET CDI GasGas MC 85 2025-2027
$582.95GET ignition option for the latest GasGas MC 85 platform.
View ProductGET CDI GasGas MC 105 2020-2024
$582.95GET ignition option for earlier MC 85/105 builds.
View ProductHPRD VHM 112cc Stroker Crank - GasGas 85/105
$1,350.00Billet stroker crank option for MC 85/105 supermini builds.
View ProductVertex OEM Replica A Piston Kit - 85 KTM Group
$114.95Service piston option for KTM, Husqvarna, and GasGas 85s.
View ProductBillet Connecting Rod Rebuild Kit GasGas MC 85
$399.95Billet rod upgrade for MC 85 bottom-end rebuilds.
View ProductKTM Husky GasGas 85 Full Engine Gasket and Seal Kit
$216.95Full gasket and seal kit for complete 85 engine service.
View ProductCommon Questions: MC 85 Platform
What is the difference between a Mod 85 and a Supermini build?
A Mod 85 retains stock displacement but maximizes efficiency. A Supermini often involves boring and stroking, which requires completely different port timing to handle the increased piston speed.
How often do I need to do top ends on a Factory Spec 85?
High-performance engines demand maintenance. We recommend rings every 10-15 hours for peak competition, though our balanced cranks significantly reduce wear on the bottom end.