Due to the custom nature of engine kits they can only be ordered via phone at this time.

Honda TRX250R Stock Cylinder Upgrade Kit

The LED/LRD TRX 250R oem cylinder engine kit is a well proven combination. LED Engine Kits are famous for putting out big horsepower, and still having the strong low-end grunt that is so important for acceleration and rideability. When used with recommended intake and exhaust components hp is increased as much as 17 rear wheel hp over stock. Our design philosophy is based on development work done with the two greatest ATV racers ever, 8-time Grand National champion Gary Denton and 7-time Cross Country Champion Barry Hawk. Development was continued with track testing by with top racers like Bill Balance, Todd Vescovi and Jeremiah Jones. We innovate with innovative features like our new O-ring sealed combustion chambers. O-ring grooves are cut into the top of the cylinder instead of using old fashion head gaskets. This system eliminates head gasket problems and allows more over sizes. There is never a problem of the piston clearance to the head or head gasket.  These important performance and reliability enhancing improvements, along with our continued developments in improving H.P. and power band width provides you with the fastest and most reliable Honda engines ever built. LED builds Engine kits for MX, TT, Cross Country, Recreation, Sand Dunes and Desert Racing. Engine Kits are available for all ATC 250R’s also. All kits include, porting, bore, O-ring mod, head or head mod, top end gaskets, wrist pin, wrist pin bearing, spark plug, brake in oil, spacer plate, long base studs, and boost ported piston.

85/86 ATC 250R, 86 TRX 250R (short rod) Top end kit – $845.95

87-89 TRX 250R (long rod) Top end kits – $924.90

TRX250R OEM Cylinder 300cc Upgrade Kit

This 72mm bore cylinder kit is based on the XC Championships winning Barry Hawk 300 kit. In 1992 Barry Hawk and Tony Kelner asked LRD to build them a big bore TRX cylinder for the XC nationals that would give good reliable torquey power. The resulting kit was used to win a number of XC National championships. We are once again making this kit available in XC, MX and Dune riding form.

Kit includes porting, sleeving, head mod, gaskets, o-rings, wrist pin bearing and Dumonde Tech Brake in oil. For long rod engines we include spacer plate and long studs.

85-86 ATC and 86-89 TRX250R Top end kit – $1200.00-$1600.00

Honda TRX250R Puma 408 Cylinder Kit

Our Puma 408cc engine kit is a 85mm bore using the stock stroke crankshaft. This kit gives the huge power gains of the big Puma cylinders are famous for, without the expense of adding a stoker crank. With almost 50 ft./lb. of torque over 67 hp it is a torquey, high hp engine with a huge power band. We have used this kit to win Super Moto and flat track events, and it is just plain awesome in the dunes. This kit includes the intake manifold and reed valve.

For ATC250R and TRX250R.

$2192.25

Honda TRX250R Puma 430 Cylinder Kit

The 430 Puma is an extremely powerful yet totally ride-able engine. Its not for the weak or the faint of heart, with as much as 52 ft./lbs. of torque and a modest 75 hp. This kit utilizes a 76mm stroke and an 85mm bore. The crank is balanced, then is welded and the crank pins are welded.
We port the cylinder for many different applications. This kit have been very successful in Ice racing, is amazing on dirt track and legendary in the sand. Reliability has been very impressive, because we use only the best components, and build to very tight standards. Reed valve, intake manifold, and crankshaft are included with this kit.

For ATC250R and TRX250R.

$3,036.41

HONDA TRX250R Sphinx 300 Cylinder Kit

Our Sphinx kits are the ultimate in the state of the art two stroke technology. The 7 transfer port design does a much better job of packing more fuel charge into the combustion chamber with out charge loss out the exhaust port at low rpm’s. This results not only in more hp, but it also contributes to a much wider power band. That means higher hp levels with more low end power and better acceleration. The triple exhaust port configuration give the needed exhaust area for maximum peak hp. The LED porting optimizes this cylinder and precisely sets port timing and angles to match the riders type and style of riding.
The Sphinx uses a Nikasil plated bore for better heat migration. The fact that the cylinder is not boreable, it allows us to build a more precise combustion chamber. This is due to not having to make the chamber larger than the bore to accommodate future over bores.
Cylinder kit include Boost ported piston, Cylinder, head, gaskets, studs o-rings and porting.

For ATC250R and TRX250R

$2,100.00 – approximate cost

Honda TRX250R Sphinx 350 Cylinder Kit

Our Sphinx kits are the ultimate in the state of the art two stroke technology. The 7 transfer port design does a much better job of packing more fuel charge into the combustion chamber with out charge loss out the exhaust port at low rpm’s. This results not only in more hp, but it also contributes to a much wider power band. That means higher hp levels with more low end power and better acceleration. The triple exhaust port configuration give the needed exhaust area for maximum peak hp. The LED porting optimizes this cylinder and precisely sets port timing and angles to match the riders type and style of riding.
The Sphinx uses a Nikasil plated bore for better heat migration. The fact that the cylinder is not bore-able allows us to build a more precise combustion chamber. This is due to not having to make the chamber larger than the bore to accommodate future over bores.
Cylinder kit include Boost ported piston, Cylinder, head, gaskets, studs o-rings and porting.

For ATC250R and TRX250R.

$1,955.45

Honda TRX250R Sphinx 370 Cylinder Kit

The Sphinx 370 is a cylinder package designed for the plus 4mm (76mm)stoker crankshaft. The increased displacement increases both hp and torque with out any loss of ride-ability or rpm compared to the standard stroke 350.
Our Sphinx kits are the ultimate in the state of the art two stroke technology. The 7 transfer port design does a much better job of packing more fuel charge into the combustion chamber with out charge loss out the exhaust port at low rpm’s. This results not only in more hp, but it also contributes to a much wider power band. That means higher hp levels with more low end power and better acceleration. The triple exhaust port configuration give the needed exhaust area for maximum peak hp. The LED porting optimizes this cylinder and precisely sets port timing and angles to match the riders type and style of riding.
The Sphinx uses a Nikasil plated bore for better heat migration. The fact that the cylinder is not bore-able allows us to build a more precise combustion chamber. This is due to not having to make the chamber larger than the bore to accommodate future over bores.
Cylinder kit include Boost ported piston, Cylinder, head, gaskets, studs o-rings and porting.

For ATC250R and TRX250R.

$1,955.45

Yamaha YFZ350 Stage 2 Engine Kit

Stage 2 takes the hp up to the next level. Adding our specially taper bored 30 mm Kehein PWK carbs and V-Force reed cages adds hp at both ends of the power band. The 30 mm carb size as proven to be ideal for the reed valve dimensions the Banshee cylinders will accept. By installing the V-Force reed cages we provide the max amount of reed valve flow that will fit the Banshee reed box. Because the V-Force cages add 4 more reed pedal openings, air flow around the edges of the pedals is increased dramatically. This shows up as a benefit to roll on power. When the pedals are open at high rpm the increase in area, makes a major improvement in air flow. The result of this carb/reed valve combination is a large power increase at low rpm as well as at the top rpm.

BEST SUITED FOR – TT/MX/Dunes
COMPRESSION – 195 psi
PEAK HP – 72 hp @ 9700 rpm
FUEL RATING – Race Gas

$2,680.18

Hot Saw Engine Kit

We offer a high performance custom engineered engine kit available for competition chainsaws. Our kit is custom designed based application and  matched up with out exhaust system. Our kit is available in different displacements, call for application. Our kits are used by Team DC Hotsaws world champion Laurence O’ Toole.

Custom Engine Kits

Don’t see your bike above? We also offer custom engine building for many different applications such as dirt bikes, ATVs (both 2 & 4 stroke), vintage applications, and competition chainsaws. Just give us a call at 503-522-2465 to discuss your engine building needs.

*Prices are subject to change.