REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo w/2104 Pipe

REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo
Price: $309.99
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The REDS Racing R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo takes the R5R V4.0 and pairs it with the REDS 2104 tuned pipe to create the perfect synthesis of quality, performance and price point.

Everything that makes the 4.0 unique is an extraordinary step forward. The R5R V4.0 has been redesigned with a redesigned 5 ports sleeve and crankshaft timing. The engine is designed with improved fuel efficiency and drivability in mind and is suitable for both Buggy and Truggy.

R5R V4.0 Improvements

  • Up to 30 second increase in runtime
  • Up to 5% increase in top speed
  • Up to 3% increase it torque

R5R Racer tuned by M.Rossi guarantees the same performance as a Pro engine at reasonable price. The 4.0 is one of the most advanced and innovative products on the market, equipped with the best technology to improve reliability and guarantee the best performance on all terrains: HCX horizontal carburetor, silicon filled and tuned crankshaft, sleeve with 5 inlet ports and classic exhaust port, high sealing front bearing, rear steel high quality chrome steel bearing.

REDS 2104
The included REDS EFRA 2104 Smooth Power exhaust guarantees smooth power delivery, with high fuel economy on your REDS engine. The REDS 2104 is suitable for any type of track where smooth power is preferred. The pipe kit includes the springs and gaskets required for assembly, as well as a short manifold. This pipe can also be used with the extra short manifold on tracks with long straights where you need more top speed and less bottom end torque.
Low - ●●●
Mid - ●●●●
High - ●●●●

Application: 1/8 Buggy or Truggy
Displacement [cm^3]: 3.5
Bore [mm]: 16.2
Stroke [mm]: 16.9
Inlet ports: 5
Outlet ports: 3
Front ball bearing [mm]: 7x19x6 rubber seal made in Japan
Rear ball bearing [mm]: 14x25.4x6 Swiss made steel
Carburetor diameter [mm]: 7
Carburetor: HCX Long needle
Weight [g]: 360
Cylinder system: ABC
Exhaust type: rear
Recommended Glow plug: REDS T5C
Recommended pipe: REDS 2143 + S
Recommended fuel: 25-30% nitro, 8-10% oil
Break-in fuel: 12% oil

Thursday, Jun 28 2018 (about 2 years ago)
REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo
only have one Word.she is one bad good 4 club racers.
Tuesday, Oct 2 2018 (about 2 years ago)
REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo
This replaced a Nova Rossi .28 motor in a truggy I bought that was at the end of its life. I only got about a quart of nitro through it before it was just ready to be retired.

Took me about 8 hours but I was able to get the initial break-in done in a day. I have about 1.5 gallons through it between the tune and runs and she's finally fallen into her final tune after about 300 laps around my local track.

Not difficult to tune. I would say most people would probably try to over-tune it by fiddling with it, but it really just takes some minor adjustments and she's ready to burn. Get the bottom end where it loads up how you like during the breakin, then when she's ready lean out the top end till she purrs.

When on a race tune half throttle is more than enough to keep up with even the fastest cars at the track. It will definitely burn the tires off your rig if you aren't careful. It ate the X2 Blockade's that were on it the first day I had it out before the tune was even complete! I've had to re-learn how to drive without destroying tires due to the insane power this thing makes.

If you mean to race, it's hard to beat this set for the money. It's about the same price for a Nova Rossi P5 by the time you get the manifold and pipe, and I honestly think this is the better motor.

Keep a look out though, for $30 more than this kit Reds sells a kit with a full clutch setup, multiple venturi ports, and more!
Verified Owner
Tuesday, Oct 29 2019 (about a year ago)
REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo
I really like the motor with matching pipe runs really good and smoot. Thanks
Verified Owner
Saturday, Feb 16 2019 (about a year ago)
REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo
There is no question this is a superior motor. Out of the box it fired right up. Not even half way through the brake in and this motor is a monster. Any one looking for an upgrade for their rtr of a choice for their buggy, this is the one. You won’t be disappointed.
Verified Owner
Monday, Nov 2 2020 (3 months ago)
REDS R5R RACER V4.0 .21 Off-Road Competition Buggy Engine Combo
Well this is my first off road power plant.

Let me first say the negative reviews you may see, on this motor and basically all known to run on this earth is due to a simple reason.

A. People don't preheat their motor and or break in properly.

As the price may look, this is not a rtr motor. The pinch is very very tight and it needs to be pre heated.

After a proper break in with pre warming and proper cooling at BDC this motor runs solid. You don't need a 700 dollar motor combo to run, you need to break them in like a 700 dollar motor combo.

Have fun.

Run Specific -
** Mine was slightly lean on HSN from stock.
** Mine pinched and stuck on break in at TDC due to my failure to keep temps up. No problems after disassembly.
** Pipe is very large. Long and a large circumference. FYI. Even with the S Manifold.

I will give it 5 stars once I win a race with it. Otherwise it's the motor I run all the time. May buy another to use as race only.