Piranha 140cc Engine
fits Pit Bikes and other Minis

Vital Information
Part No WHS-1143
Stock Level In Stock
Choose Options

This is the famous Piranha 140cc Engine.

Often refered to as the YX140cc, this is our ALL TIME best selling engine.

Top performance and economy all in one.

This is a Super sturdy and Very strong running engine.
At TBolt we offer the latest version available with larger kicker shaft and all of the most current improvements.

Front Drive Sprocket Included

See picture for included parts.  Engine available as pictured.

We've had tremendous luck with this engine, and it's a Great Replacment engine or for builds & Projects.

Engine Kit Includes:

  • Engine
  • Intake
  • CDI
  • Coil
  • Harness
  • Kicker
  • Shifter
Displacement 140cc
Engine Type Air Cooled, Single-Cylinder, 2-valve, 4-stroke
Bore/Stroke 56mm x 57mm
Final Drive Chain
Fuel Delivery OEM 22mm 
Fuel Unleaded / 91 Octaine
Reccomended Engine Oil 10W-40 Petroleum Based (Nonsynthetic)
Kick Start Yes
Electric Start no
Auxillary Output (lighting) Yes
Transmission 4-Speed Manual 4Up
Shift-Pattern Four-speed Transmission: N-1-2-3-4
Clutch Rear 5 plate manual

Note:  When upgrading your Honda XR50/70 or CRF50/70 to this engine you may want to order  an aftermarket footpeg mount and tank spacers. Also we suggest using an aftermarket exhaust to obtain maximum performance. All of these items are availble at TBoltUSA.com

Engine Specs

Bore: 56mm
Stroke: 57mm
Displacment: 140.4cc
Valves: Big Valve 27mm/23mm head
Gears: 4-speed, bottom neutral 4-up shift pattern
Carb: 22mm mikuni
Ignition: Standard Flywheel ignition


Not Included

  • Skid plates
  • Exhaust
  • Air filter
  • Clutch Cable (necessary if switching from Semi-Auto Transmission)
  • Throttle Cable 
Important Upgrade info 
*VM26 606 TBW0399 carb upgrade includes TRC-0559 Boot  


  • You may want to consider setting up the bike on a stand for a solid starting location at first until your confident
  • Turn on Both Fuel and Choke
  • DO NOT open the throttle (do NOT turn the throttle)
  • Move the starter down until it gets stiffer, your looking for top dead center
  • Let the starter come back up and give a full strong swift kick ALL the way thru
  • REPEAT (If necessary)
  • When warm just do not use the choke

Flooded Engine:
IF your flooded , pull the plug, kick it over about 10 times WITH THE PLUG OUT
Put in a NEW PLUG

For ease of starting:
You may want to consider our TRC EZ START HIGH PERFORMANCE CDI
Part No. TRC-9745

One more thing:
I find at times it helps to just crack the throttle a tiny bit to let air in, just a tiny bit

Available Options:

Carb Choice:

Clutch Cable:



Uni Air Filter:


Since 2004, every purchase from TBolt USA includes access to technical support
from our staff of experts and our online Pit Bike Technical Info Database!
We have all necessary support parts on hand.
Most orders ship same, or next business day, unless otherwise noted above.

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