Mikuni TM42 | MuZ MZ Skorpion 660 | Pumper Single Carb Conversion Kit | LH Throttle

Mikuni TM42 Pumper Flatslide Single Carburetor Conversion Kit — the ultimate high-performance upgrade for MuZ Skorpion 660 models (Yamaha 660 engine), delivering the most impressive power gains available over the stock twin-carb setup.

This is Mikuni's top-tier flatslide carb (larger and more advanced than the TM40), offering razor-sharp throttle response, massive torque and horsepower increases, and elimination of common OEM issues like hard starting, hesitation, bogging, and flat spots. Expect wheelies in an extra two gears or more — hold on tight for that first full-throttle pull, as it can be surprisingly aggressive!

Key fitment note for MuZ Skorpion 660:

• The standard factory Mikuni TM42-6 (right-hand throttle cable entry) is the more budget-friendly option but requires a simple tank modification for clearance under the fuel tank.
• This kit features our custom-modified TM42 with the throttle cable connection lowered and relocated to the left-hand side — no tank heating or depressing needed for perfect clearance with stock or aftermarket tanks.
• (This same LH-modified approach has been a proven winner on Honda XR650R setups for years, avoiding larger tank mods.)

Tank modification option (for the standard RH-control TM42 – cheaper carb version): A competent DIYer can easily create clearance by heating and gently depressing a small area on the underside of the polyethylene tank (after fully draining fuel). Use a heat gun to evenly warm the spot to around 140°C until soft, then carefully form a contoured channel with a broom handle or similar tool. Shield edges to protect paint. The material retains full strength once cooled — no thinning or weakening if done evenly. Takes about 30 minutes with test fits. If unsure, have it done professionally. The performance payoff makes it well worth the effort.

This kit is also a favorite single-carb conversion for: Honda XR600/XR650, Suzuki DR650, Kawasaki KLR650, KTM big singles, Yamaha 600/660 models — especially when stock carbs are worn beyond repair or just frustrating.

Kit highlights (Basic version – designed for pod filter use; pod not included):

• Genuine Mikuni TM42-6 pumper flatslide carburetor (accelerator pump for instant, crisp response).
• Custom PA11 carbon fiber-reinforced nylon 2-into-1 manifold with mounting hardware and gaskets.
• Heavy-duty rubber engine mounting sleeve with clamps.
• 1/4-turn quick-action throttle.
• Push/pull nylon-lined throttle cable set (lubricate during install for smooth, long-term performance).
• Pre-installed jets optimized for common conditions worldwide, plus spare main jets for WOT fine-tuning.
• Cable choke (rarely needed) with universal mounting bracket.

Installation tips:

• Requires cutting the front of the airbox to fit a high-flow pod filter (e.g., 150mm long Red Uni-Filter with sock or similar large cloth/paper pod).
• The LH-control TM42 (this kit) and TM40 pumper clear the tank without mods. Budget TM38 or standard RH TM42 kits need the tank depression.
• Interested in retaining the airbox? Check our Yamaha Belgarda 600 or 350 kits for adapter ideas — we may have compatible parts. Contact us to discuss.

Why the TM42 stands out: Born from Mikuni's legendary HSR42 (which revolutionized Harley performance in the '90s with roller-bearing slide, superior venturi, and huge power gains), the TM42 brings that same race-proven tech to big Japanese singles. Better atomization, larger fuel bowl, lighter pull, and precise mixture control mean more top-end power without sacrificing bottom-end — often gaining low-end torque on smaller engines.

Fuel economy: You'll use less fuel than worn stock carbs when riding conservatively — the efficiency is impressive. But with so much extra power on tap, that same throttle twist can turn into wheelies and traction-breaking fun. More horses = more hay when you let them run!

This kit unlocks your bike's true potential for smoother, more responsive, and far more exciting rides. Proper tuning (altitude, climate, fuel octane, exhaust/cam/head mods) ensures it stays spot-on for years — we include a wide jet range to cover most scenarios worldwide.

Ready to transform your Skorpion? Grab the kit today and prepare for an adrenaline rush. Questions on fitment, tank mods, jetting, airbox options, or tuning? We're here to help — contact us anytime!