Skyhawk Instructions



WEB SITE REFERENCE: Instructions Copy Righted: Rev. Dec 1, 2011

GT2A > 1.4Kw 48cc / 40mm x 38mm bore and stroke: Square Head. 203 crankshaft brgs.
GT2B > 1.4Kw 48cc / 40mm x 38mm bore and stroke: Round Head. 202 crankshaft brgs.
GT5 > 1.6Kw 66cc / 47mm x 38mm bore and stroke: Square Head; 202 crankshaft brgs.
Kit Box Contents:
Due to many kit options and rules of different countries contents may vary:
2 cycle crankcase scavenging gas/oil mix engine with 2 point fixed mounting; Exhaust muffler; Tear Drop 2.5L Fuel Tank plated inside; Drive chain; Chain guard; Sprocket with 9 hole mounting hardware for 36 spoke wheel; Chain idler; Push button clutch lever, Carburetor; CD Ignition, Twist throttle with kill switch: Control cables; Tool kit with extra service parts;
To ensure engine performance: DO NOT use other than original SkyHawk replacement parts.
Note: Mechanical aptitude and experience is required to perform this installation. Many "Do It Yourself" mechanics will find this project rewarding. A love of small engines is the only requirement for this project. However, installation is sometimes best done by a professional auto or motorcycle mechanic. Frame size should be 28mm to 30mm dia. with 70 degree included V angle. For sufficient engine clearance select a bike with a seat tube length of at least 12 ½ inches measured between bottom of top tube and top of pedal sprocket tube. A rewarding joy and challenge is found in designing a custom installation of your own. Remember, a quality installation is paramount to safe usage and long term satisfaction. You may find many other uses for this engine kit such as for stationary machine power or 4 wheeled off road riding machines. Have fun and good luck on your motorized project.
STEP #1 Mounting the Engine:
1. The engine mounts in a “Vee” frame. It is best to make sure all 4 engine studs are securely bottomed out in the engine before mounting. Use a Jam nut procedure to tighten.
2. Consider using Masking or Duct Tape on the front down-tube & seat tube of your bicycle to protect the paint finish while test fitting the engine to your donor bike. If the distance between the two frame tubes exceeds the engine mounting span then additional spacers or welded brackets may be required. Mount the engine to the seat tube first and then fit to the front tube. If frame tube fit is smaller than engine clamp dia. use strip shims to fit. See examples of Ft Mt installation on a big downtube bike frame.

Big dia. downtube Front Mounting Ideas you can make or buy:

a.) Flat Plate with Single U Bolt: b.) Dog leg plate and single U bolt:
c.) Curved Plate with dual U bolt: d.) Welded on Pedestal mount design.
d.) Pedestal front mount with rubber cushion for weld on application;
Rubber wrap should also be used to isolate the rear mount on the seat tube if an alum. frame is used.
3. If the rear frame tube from the seat down to the pedal sprocket is too small to fit the rear engine mount, a rubber shim can be made from an old bicycle rubber inner tube. This also helps reduce engine vibration. Engine needs to have the carburetor set in a level position. Too much engine tilt can cause chain to hit the drive cover and engine to not run correctly. It is best to have the drive chain to rear wheel sprocket be as horizontal as possible with no more than 15 degrees max engine tilt. After the desired engine location is determined mount the engine to frame. Appling LocTite thread lock is recommended to avoid loosening due to vibration. Note: All threads are metric.
ChainWheel Sprocket Installation:
     The Drive Chain Sprocket has a 36.9 mm dia. center hole and mounts on axel hub on the left side of the rear wheel against the spokes dish side in. The sprocket must fit over the hub in a perpendicular plane with the axle. This insures that your rear chain sprocket spins true with the rear bike wheel. *NOTE: On some older bike axle hubs like on coaster brake models it may be required to slightly enlarge the sprocket center hole to obtain a flush, and concentric fit next to the spokes. This is best done on a engine lathe by a professional machinist.. . It is also recommended that the rear wheel be re-spoked to 12 ga. spoke wires to insure long life. Most any Bike shop can do this operation for you. Applying thread adhesive and equal tightening of the sprocket bolts. This keeps the chain sprocket true with axle and free from wobble while spinning. With bike upside down spin wheel and check sprocket for wobble. The chain can jump off the sprocket if the sprocket installation is done incorrectly
1. Place rubber isolator next to spokes and locate sprocket on axel hub with curved side next to spokes, shinny side in. Cut the rubber isolator ring between holes in order to fit INSIDE the spokes and around the axle. Install the 5 split steel retainer plates 3 in and 2 out next to the rubber isolator and insert 9 bolts.
2. Secure with 9 bolts compressing the chain sprocket to the spokes. Note: Rubber isolators may be needed on both sides or on one side of sprocket for chain alignment, install as required:
3. The Chain Sprocket on the Wheel must align within 1/2 cm to the Chain Sprocket on the Engine.
Figure #2
1. Slice cut 2 Rubber Isolator Rings and install on both sides of spokes.
2. Install 9 hole Chain Wheel Sprocket mounted with shinny concave side inward:
3. Install three 1/3 plates first and then the two ½ Moons on top to form a lock..
Options available from your dealer:
The drive chain can be easily shortened to the correct length. Special tools are required to remove and replace the master link when shortening the chain by removing links. Ideally, both your pedal drive chain and your engine drive chain should have the same tension.
A. Remove left rear cover plate from engine. This is the plate next to and under the clutch swing arm.
B Your engine may come with a standard bike chain or with a Heavy Duty 415 chain depending on how it was ordered by your dealer. Engine drive sprockets are different depending on chain size. The 415 chain uses a wide drive sprocket and the std. bike chain uses a narrow one. A 415 chain will work with a narrow sprocket but a std. bike chain will not go over a wide drive sprocket. Note: Install chain with master link clip on outboard side of the primary drive sprocket teeth. ( Note: wide tires larger than 2.125
may rub on a wide 415HD chain: )
C. Use supplied spark-plug wrench to turn engine crankshaft sprocket to feed chain around it. Do not pry sprocket with a screwdriver or similar object.
D. Fit chain, measure and remove excess links to assure proper length. Be sure master link connection rides on the inboard side of the primary drive sprocket or interference of link and sprocket can occur. Proper chain length is when top chain has ¼ inch to ½” deflection with the bottom side of the chain loop tight.
E. Chain tension adjustments can be made by pulling rear wheel back if frame has straight slot wheel drop out. If both chains can be adjusted equally then installing chain idler on the wheel strut may not be necessary. At installer’s discretion the chain idler can be installed on either the pedal chain or engine drive chain.
F. Install supplied chain safety guard by attaching to engine and wheel axle struts.

Clutch cable installation and adjustment:
A) Install clutch lever to left side of handlebar and attach cable end barrel into lever slot hole.
B) Squirt oil down the cable sleeve: Route clutch cable through the ball-mount on motor with the big spring around the cable acket and ahead of the ball mount. The big spring serves as a cable heat shield.
C) Insert cable wire through small spring and route through clutch arm and attach brass cable-end and screw. Adjust cable tension to allow very slight play in arm. Handlebar clutch lever must be in the released or outward position to complete this operation.
D) Activate lever a few times, and check clutch arm for slight free play: About 1/16” engine clutch arm free play is required with the handle bar lever in the released in what is called clutch engaged position or the engine will fail to start if cable is too tight. Re-adjust as required.
E) Basics of clutch operation: The handlebar lever pulls the cable that moves the engine clutch arm. In turn the clutch arm pushes a rod through the motor that pushes the clutch plate out. ( similar to a car clutch.) Releasing the handle bar lever engages the clutch and provides engine torque to the drive chain or to start the engine. The clutch friction allows engine to start, and also transmits engine torque to the drive chain. When the bike is in the pedal mode the handle bar clutch lever is locked inward in the catch notch. The bike then operates in default as it would without any engine. Periodic clutch adjustment is necessary to maintain efficient operation *NOTE: Cut off excess cable from clutch arm, before operation, to avoid possible interference with pedals, chain, or your legs, etc. See Figure #4.
Carburetor and Throttle Installation:
Install CDI module on down tube as far away from engine heat as possible.
First install Blue & Black wires from engine magneto to same color CDI wires. Warning: Do not hook up backwards or damage will occur to the CDI. Next install the throttle handle kill switch wires into the 2 remaining open holes of the 2 CDI wire terminals. Push the clear rubber protectors over the 2 connections and tape with black electrical tape. The remaining white wire from the engine is not needed unless you want to run a small wattage 6V headlight but it's not recommended as it will rob engine ignition power requirements so is really best to tape this wire up securely or just snip it off at the engine exit plug. Use a heat shrink tube over the wire sheathing to keep water out of the magneto box.
The "Magneto" is the heart of the ignition system and is activated by rotation of a permanent magnet rotor. When a N/S magnetic flux field rotates past the magneto coil an induced voltage is sent to the CDI via blue / black wires so as to fire the spark plug at the right time.
Engine firing timing is not adjustable; Position of p/m rotor is fixed to ensure correct timing.
If engine does not fire at start up check all bullet connections. Check if kill switch has an unwanted ground. Make sure magneto has a good ground and not insulated by varnish.

( NOTE: Engine Kits to USA have a Fuel Line EPA approved for permeation rating )

Procedure for attaching throttle cable to NT & SPEED carburetor slide valve:

The small stop on the cable wire end slides through the long groove on the slide valve. Early slide valves were made of brass and later ones are made of black plastic. Beware that there are 2 sizes of black plastic slide valves. Normally; 14.95mm dia. for 66cc and 14.42mm dia. for 48cc are used but slide valve must match the appropriate carb. housing hole dia. to work. Jet sizes are available from 0.80 to 0.65mm.
Note: Speed Carburetors have fuel shut off valve and bowl drain petcock; Also these carbs. have larger 14.95mm throttle slides and outlet openings than found in X brand carbs. The square red or the square black AC is interchangeable with small white or black round versions.

Be sure to check carb. air cleaner attach screws for tightness before installing engine: Air cleaner screw coming loose and entering engine is not covered by warranty;

A.) Note component positions in pictures; Needle clip is factory set in second slot: If a more rich gas mixture is required you can move the jet pin "pac man" clip to the next lower position notch.)
When the throttle is twisted a spring inside the cylinder valve is compressed and the slide valve is raised to give more air & fuel to the engine. For this to work properly the throttle must twist freely on the handle bar in both directions prior to the cable being installed.
B.) Install twist grip throttle on right side of handlebar end. On some handle bars it may be necessary to ream out the handle ID to fit the bar so that the throttle will twist freely. It never hurts to add a few drops of light wt. oil to let trickle down the cable inside the full length of sheathing.
C.) After installing cable inside the carburetor you are ready to mount it on engine intake tube and tighten clamp screw. Mount the engine so carburetor sets as level as possible.
Internal parts of #3 & #4 YD &YuanDong Carbs are not the same as old style #1 NT & #2 Speed carbs
OFF SET Z CNS Carb Kit: Use this long Z intake tube if bike seat tube has a clearance problem.
Fuel Tank installation
A) Attach fuel petcock to tank. Use Teflon tape to seal threads. Careful not to strip threads.
B) Mount tank on bike top crossover frame with two supplied brackets and nuts.
C) Attach fuel line from tank to carburetor. Best to use USA made fuel line like GoodYear SAE 30-7 4.8mm obtained from local automotive stores like AutoZone. Factory supplied clear plastic line gets hard over a period of time. *NOTE: Filters are contained in the petcock and in the carburetor inlet. If engine runs poorly clean the valve filter as residue from the tank may have clogged it.. It is highly recommend that a tank liner coating be applied inside the tank before installation. This product known by the names of; KBS, Kreem and Flowliner and is available from most motorcycle dealers;

!WARNING! Remember safety first: Wipe up any spilled fuel. NEVER fuel a hot engine or smoke while fueling. This could result in sudden fire, personal injury. Always move your motorized bike at least 10 feet from any fueling area before attempting to start it. Never leave the tank fuel cap off after fueling as rain water will contaminate the fuel and cause engine failure.
# 1. How to Adjust Clutch if signs of slipping or squealing are encountered :
A) Disengage the clutch by pulling handle bar clutch cable lever inward and push the lock button in.
B) The bike should now roll easily. Release the clutch lever and bike should slide the rear wheel.
C) If the rear wheel does not slide when the lever is released this means the clutch needs adjusting.
D) Remove the clutch cover and then remove the locking screw that holds the Clutch Adjusting Nut.
E) Pull the clutch lever arm on left side of engine inward. Back off the Clutch Adjust Nut ½ turn CCW.
F) Release clutch lever arm and check for 1/16" slight clutch arm free-play.
G) Readjust *Clutch Adjust Nut as required to get the required 1/6" clutch arm free play.
H) Now Repeat the B) roll test. Rear wheel should now slide when the handlebar lever is released.
I) Be sure to re-install the small locking screw in outer edge of *Clutch Adjust Nut.
G) Good idea to place a small gob of grease at gear mesh area. Use grease sparingly! Then replace cover.
H) Squirt light grade oil down clutch cable sheathing to reduce friction and make for easy lever pull.
#2. Carburetor
Carbs now sent to the USA per instructions from the Dept. of EPA the idle and air fuel mixture screws must be epoxy sealed or made non adjustable at the factory to avoid end-user tampering. NOTE: Carbs sent to all other countries DO NOT have these air/fuel adjustment restrictions. Depending on your dusty riding conditions, clean air filter every 5 to 20 hours of operation by removing the filter cover to access the screen and element. Wash element with a degreasing agent such as Simple Green™ or Purple Stuff™. Be sure element is completely dry before re-assembly. NOTE: If engine runs poorly clean tank shut off value filter.


#3. 3 pt. Spark Plug
Remove spark plug and inspect for excess carbon build up. Clean, re-gap to .0.036" of an inch if necessary. Check plug after every 20 hours of operation. New spark plugs are available from your selling dealer. Be careful using aftermarket spark plugs as heat range and threads differ greatly. An extra plug is included: When replacing the spark plug in an Angle Fire head it's best to use a 3 point electrode spark plug P/N Z4JC to ensure total combustion. ( Ask your selling dealer for it by part number. )
#4. Exhaust system
After 50 hours of operation check exhaust pipe for excessive oil and carbon build-up. If muffler is clogged your dealer has replecements.Make sure attaching nuts are tight and no exhaust leaks are occurring. Be sure to use supplied support strap to secure exhaust muffler to a solid anchor point on bike frame or engine.
A) To remove inside catalytic exhaust insert loosen the retaining screw on end cap and remove.
B) Pull cap and baffle out of pipe. Note: Some catalytic inserts are welded in and cannot be removed. If you need a replacement muffler contact your dealer. 2010 models have an air shield welded on the outside of muffler again per EPA rulings. This insures hot run so catalysis can clean the exhaust.
C) Clean with degreaser, rinse and dry. Re-assemble: File muffler attach flange to have smooth flat surface.
D) Always use a new exhasut gasket and good idea to use double nuts on muffler attach studs;
*NOTE: Excessive periods of low speed operation, idling or leaving fuel petcock in the “on” position during shut down periods may cause the muffler to become clogged with unburned fuel.
#5. Standard Bike 1/2x1/8” Chain is included in kit. HD 415 is available as an option.
Every time the bike is ridden check the tension of the drive chain by:
A) Rolling to bicycle forward to remove slack from the bottom of the chain.
B) Find the center and push downward on the top of chain while measuring the deflection.
C) Tighten chain if deflection is more than ½ inch.
#6. Head Bolts
Tighten all fasteners after each five hours of operation. Most important to check Cylinder head bolts : Tighten in a X pattern to 10 ft/lb using a torque wrench. A two piece cylinder and head design engine requires head bolts be kept tight. Important: Check head bolts before each and every long ride, vibration can cause them to loosen and blow a head gasket. Caution: Do not over torque or head bolts may break off. ( Twisted or broken head bolts due to over tightening is not covered by warranty. )
#7. Right side gears:
Remove cover plate and keep small amount of heavy grease on gear train. Do not over grease as leaks will occur and also may adversely affect clutch operation. Regular greasing if required will help reduce gear wear and keep gear train quiet.
#8. Left side drive:
Routinely pack grease on the clutch 47mm long push rod located at the 10T sprocket and also in cover hole around the lever cam. This will make easy clutch lever operation.
Items, tools and extra service parts in tool kit; Typical Engine ID plates:
General Information
Obey all traffic regulations. Always wear a helmet while riding. Remember that you are riding a motorized bicycle and other traffic may not be able to see you. Never operate your motorized bicycle on a pedestrian through way or sidewalk while the engine is operating. Never operate your motorized bicycle in an unsafe manner. Check local and state laws before riding on streets & wear a helmet.
IMPORTANT: PLEASE READ THIS: Gas and OilMixture for Fuel ratio
The engine is a 2 cycle design, therefore, a gasoline/oil mixture is necessary. During the break-in period (1st gallon of fuel), the ratio is 18 parts gasoline to 1 part 2 cycle oil. After the break-in period, the ratio is increased to 25 parts gasoline to 1 part oil. The engine crankshaft bearings are lubricated from the oil in the gas mix. A rich break in mixture ensures bearings will not cease. !WARNING! Remember safety first: Wipe up any spilled fuel. NEVER fuel a hot engine or light a cigarette while fueling. This could result in sudden fire, personal injury. Always move your motorized bike at least 10 feet from any fueling area before attempting to start it. Never leave the tank fuel cap off after fueling as rain water will contaminate the fuel and cause engine failure.
Step #1. After filling tank with the correct oil/gas mix open the tank fuel valve. Fuel line is in the open position when the small lever is pointed down. Move choke lever to the on position. This is the small lever at the end of the choke cable All the way Up the choke is on. All the way Down the choke is off. Move progressively downward to off position during engine warm up period.
Engine Starting procedure for Lever Clutch Models:

1. Pull the handlebar clutch lever inward, to disengage the engine from the rear wheel.
2. Pedal; (down hill if possible for first start)
3. A mid frame or rear wheel bike stand is helpful to start the engine in place.
4. Let out the clutch lever all the way out and continuing to pedal. The result is a direct engine hook up via the friction clutch with the rear wheel via chain and sprocket. The engine will now start spinning, Pedal until motor starts. Accelerate slowly at first..
5. Twist throttle to increase speed, reverse twist throttle to decrease speed. To stop, disengage clutch and apply brakes. To accelerate, pedal and release clutch while opening throttle.
6. Adjust choke to the smoothest engine running position.
7. After warm up push choke lever all the way down. If engine races too fast, or too slow, pull clutch lever and lock in the notched catch, stop and adjust engine rpm.
8. If the rpm needs adjusting, turn the idle adjust screw found on the right side in or out slowly to obtain the proper idle speed of about 1500 rpm +/- 100 rpm. CW to increase and CCW to decrease rpm.
To correctly break the engine in, do not exceed 15 mph or exceed 30 minutes of continual running for first tank of gas. Note: Engine will develop more power after break in.
9. To stop the engine, push Kill switch and turn off gas valve at tank. Turning off the gas will prevent fuel from being siphoned from tank. Warning Note: Never leave the tank gas valve in “open” position” when engine is not running or the bike is in storage.
10. After or before each ride check all mounting fasteners, including hd. Bolts, axle and brakes.
11. Warning Note: Engine lock up or piston seizure due to improper gas / oil mixture will not be covered by factory warranty. This the responsibility of the owner / operator to make sure the gas and oil is mixed correctly.

YuanDong SkyHawk mfg. > WARRANTY POLICY:

This is a parts kit: The installer is the prime contractor and accepts all product liability. Proper use and maintenance is required for the continued enjoyment of a motorized bike. This product has been manufactured to strict quality control standards. For kit parts warranty policy contact your selling dealer. Warranty approval is subject to factory inspection and only the defective part or parts will be replaced, not the complete kit or engine. Only the defective part or parts should be returned to the selling dealer for his warranty replacement consideration. Your dealer may require you to obtain his authorization before returning defective parts. Include description and picture of failure with as many details as possible. Note: Seized pistons due to improper gas / oil mix or shipping damage due to carrier neglect is not warranty. Inability to install or adjust components is not warranty. Failure caused by loose fasteners or loose head bolts not being torque regularly is not warranty. Failure to get the engine to run at max power with inferior fuel is not warranty. Failure to adjust carburetor idle setting. Clogged up inline fuel filters is not warranty. Broken bolts and or broken castings due to over-torquing of fasteners is not warranty. Broken drive chains is not warranty. Use of nitrous oxide gas for power boost voids warranty. Use of KickAss Bottle boost does not void warranty if used per instructions. Failure to adjust clutch operation is not warranty. Milling the head, or cyl. bottom to increase compression voids warranty. Rust in gas tank is not warranty as all tanks should be KBS, Kreem or Flowliner coated inside before installation. Before calling your dealer about an engine problem review the step by step trouble shooting guide listed here-in on page 27.
When replacing the spark plug in an Angle Fire head it's best to use a 3 point electrode spark plug P/N Z4JC to ensure total combustion.


Chrome parts for engine dress up are available from your selling dealer;

Engine Shift-Kit for multi speed bikes.

MSK = Multi Shift Kit:

Allows using the bike's right side rear wheel multi speed derailer system to work like a transmission for hill climbing or extra speed. However, engine pedal starting is a little more difficult. An optional left side engine recoil rope pull starter is recommended if it will clear your bike pedals. MS kits are available in USA aftermarket from Sick Parts Co. and also from SkyHawk factory with a Brazilian designed version pre-installed on the engine for a 3F labor saving >> form, fit and function benefit.
Should you be lucky enough to find a dealer who has one of our GT2 special bikes made for motorizing you can't go wrong. These bikes have thicker frames along with GruBee HD axles with hub mounted sprockets utilizing a 3 brake system and built-in gas tank. Gt2A is made of alum. alloy!

GT2A frames w/ rubber mt. are now available for WD distribution:

C. For Standard NT and SPEED carb. ( Not for #1 or #2 CNS Carbs.)

The ETHANOL 101 Home Study Course

What you need to know about Ethanol fuel when used in small engines;
      Outdoor power equipment dealers and mechanics are finding themselves dealing with a flood of frustrated owners experiencing engines not running right or having gummed up carburetors only to bring them back a month or so later with the same complaint. What the customer does not realize is that the problem is not the engine! It's the fuel!!!!
      The introduction of ethanol, otherwise known as alcohol, into the fuel has caused a wide range of problems. While ethanol is regarded as a fuel, blending it with gasoline results in these 4 conditions.
  • Rough idle:
  • Hard starting after leaving the engine sit idle, ( not used ), for several weeks :
  • Gummed–up carburetor jet:
  • Loss of power:
  •       Ethanol in gasoline breaks down and forms gums very quickly. Ethanol and Gasoline do not chemically bond with each other, instead they are held together in a loose colloidal suspension much like you would see in an oil and vinegar salad dressing mix. The fact is ordinary fuel adjustment additives developed 50 years ago and still on the market today do not correct these 4 ethanol problems.
          1. Debris in gasoline caused by Ethanol.
          Varnish Gums form in the fuel tank and in the carburetor bowl as E5, E10 & E15 ethanol fuel ages. These particles can clog Filters and Needle Jets. Modern day fuel additives break down the enzymes into sub micron sized particles that can be easily burned during the combustion process.
          2. Excessive water in the fuel and phase separation.
          Ethanol attracts moisture from the atmosphere and forms a ethanol and water mix in the gasoline. Ethanol blended fuel will naturally hold 0.5% water in separation, but when water levels exceed this threshold, or when fuel cools significantly, the water/ethanol mix drops out of suspension which is called phase separation. Excessive water in the fuel causes engines to run rough, stall and can lead to internal engine damage. A good fuel additive allows the water to mix with the fuel and get burned off to create a dried out tank result.
          3. Ethanol fuel breaks down quickly.
          As ethanol evaporates the fuel looses octane and becomes what is known as "stale". This causes hard starts and engine rattle as well as loss of power and engine damage. A good fuel additive will enhance correction to fuel break down for up to 2 years.
          4. Ethanol causes lost power and lost performance.
          Ethanol added to fuel does not allow as much energy as traditional gasoline. This results in poor engine performance. A good adjustment additive will break apart large clusters of fuel molecules, creating more surface area. This in turn allows additional oxygen to react during combustion which results in complete fuel burning and reduces toxic exhaust emission.
          The laws of some states in the USA do not require the gas station to tell you how much ethanol is in the gas they sell. E-10 or 10% is supposed to be the legal ethanol limit but up to 50% has been found in some off-brand gasoline. Adding a dry gas additive is not the answer either as these products contain more alcohol which now you know is really Ethanol and will just accelerate the problem into the realm of the third kind.
          Having said all the bad news here's some good news! There are some additives on the market that will in fact correct the short comings of having Ethanol in gasoline and will allow easy starting even after extended long periods of not running the engine. These additives must contain enzymes that allow more oxygen to bond with the fuel hydrocarbons thus allowing a more complete combustion burn of the fuel charge. This translates into these advantages.
  • Easier Engine Starting:
  • Better throttle response:
  • Decreased exhaust emissions and decreased visible exhaust smoke:
  • Prevention of varnish gum deposits:
  • Increased fuel economy:
  • Helps prevent Phase Separation that can occur in stored fuel when water and ethanol bond together and then falls out resulting in degraded fuel that prevents good engine performance.
  •       The best policy is to avoid using any gasoline with Ethanol in it. This 101 article does not recommend any brand of additive for Ethanol correction, however here's a brand claiming to have benefit; 

    GGG-2 48cc & 66cc Dual Start Models
    Centrifugal clutch operation> Rope Pull & Pedal start:

    Centrifugal clutch has over-running mechanism to allow engine pedal starting and can also be rope pull started. Long screw shown above is a tool used to remove clutch from shaft.
    How to Start: After completing Step #1. for a standard engine pull the recoil rope or engine can be pedal started just like a friction clutch model. Use a wax coating on the pull rope to avoid breaking and ensure long life. Accelerate slowly at first until engine warms up and choke lever is pushed all the way down to off position.

    Note: End user or installer is the vehicle manufacture. End user assumes all product liability and assumes all compliance to the laws of the land; Quality installation is paramount for safe operation.