O.S.SPEED R21-M06 - 2025 Minicars Marine SE Racing 3.5cc Engine
This is the new 2025-edition Minicars Marine Special Edition O.S.SPEED R21-M06 3.5cc long-stroke competition engine. The R21-M06 has a new piston & liner, a new conrod, a new crankshaft & a ceramic main ball bearing.
Features:
- New DLC coated & balanced R21 Euro-II crankshaft with more timing
- New 9-port cylinder liner with 3-port exhaust
- New piston with 3 oil-grooves
- New Ceramic main ball bearing
- New Reinforced "R" conrod
- New RP6 Turbo plug (instead of RP7)
- O.S.Speed developed black crankcase with Minicars Marine Laser Engraving
- Black anodized water cooling head with Minicars Marine Special Edition Laser Engraving
- Backplate with steel thrust plate for lower friction and increased durability
- No carb included - choose your own carburetor (15mm diameter neck)
Suitable for competition boats (experience level ”high”):
- Hydroplanes
- Offshore (with gear deduction)
- Endurance (with gear reduction)
Recommended fuel:
- Hydroplanes: 12% nitro fuel with 8% Klotz Original Techniplate + 8% Klotz Benol oil
- Offshore: 12% nitro fuel with 8% Klotz Original Techniplate + 8% Klotz Benol oil
- Endurance: 12% nitro fuel with 8% Klotz Original Techniplate + 8% Klotz Benol oil
- We don't recommend running the engine with less oil than the above recommended levels. You may add more recin/castor oil (Klotz Benol) in extreme conditions and heavy loads.
9-port sleeve with re-designed ports with improved flow for more torque and a new piston with 3 oil grooves.
Newly designed reinforced "R" connecting rod is now stronger to withstand even more abuse.
The rear bearing is now ceramic.
New DLC coated and balanced crankshaft from the R21 Euro II engine for more power overall.
Steel insert backplate for less friction and more durability.
Marine cooling head with Minicars Marine laser engraving
New combustion chamber with smaller volume for lower nitro levels.
Specs:
- Displacement: 3.49cc
- Bore: 16.08mm
- Stroke: 17.2mm
- Crankshaft dia: 14mm
- Practical r.p.m. Range: 4.000～43.000
- Output: 2.76hp @ 35.000r.p.m.
- Weight: 265g
- Water Cooling Nipple Thread: M5x0.8
Included:
- O.S.Speed R21-M06 2025-Edition Minicars Marine Engine
- RP6 Glowplug
- O.S.Speed flywheel cone
- O.S.Speed decal
- Printed Manual & partslist
