Pocket Bike -
FAQ

1. What exactly is a pocket bike (mini moto)?
   A pocket bike is a miniature GP Racing motorcycle. It stands about 15 to 18 inches high depending on the model and brand weighing anywhere from 35 to 55 pounds. Pocket bike Racing is a rapidly growing sport for both children and adults, and by their nature are just pure fun to ride. Although they may appear to look like toys, the European mini motos are built to high quality standards of accuracy and proportion of a the world class GP bike.
2. How do pocket bikes handle in comparison to a full size motorcycle?
   A pocket bike handles much like a larger motorcycle, but because the wheelbase and weight are much less, it changes direction quicker. The front wheel of the more powerful pocket bike models can rise up without hesitation with the application of power; also due to the short wheelbase, they can turn very quickly. This in most peoples opinion adds to the fun factor, but demands that the rider has protective clothing, and is familiar with the bike in question.
3. I'm a concerned parent, are pocket bikes safe for my children?
   Any performance-oriented machine can be inherently dangerous, especially if operated by a non-adult. In this circumstance a pocket bike is no exception. Most pocket bikes are geared for speeds of up to 40 MPH or more. A pocket bike can be safely operated by someone over the age of  7 years old, however only when supervised by a responsible adult. As in any circumstance, propery safety equipment is essential and should be made to fit properly to whatever age and / or size the rider is. Restrictors are available for pocket bikes that can help govern top speeds.
4. Where should pocket bikes be ridden?
   A pocket bike should never be ridden on the street. It should only be ridden on hard surfaces with no traffic. With permission, a large parking lot or other privately paved area can be an ideal place to ride. Always be aware of your local laws pertaining to this type of recreational activity. Laws can and may vary depending on which state or country you live in.
5. How fast do pocket bikes go?
   Most Blata powered pocket bikes will accelerate quickly to about fourty five miles per hour. The speed can be modified more or less depending on optional performance upgrades and sprocket sizes.
6. Do pocket bikes accelerate quickly?
   Yes! However this may not be true for all pocket bikes, Blata pocket bikes are known to have fantastic acceleration speeds. Be warned, there is a huge difference when comparing to lower cost non European bikes.
7. I've heard there are a couple of power bands, what does this mean?
   Two stroke engines by design generate a lot of power, this is due in part to the power stroke that occurs with each rotation of the crankshaft. Typically, a two cycle engine can make much more power than its four cycle counterpart due to its small cubic inch displacement; The smaller stroke (length of piston movement) causes higher engine speeds, resulting in higher output. This in turn produces a power band that may not be as controllable as the four stroke engines. The high powered Blata engines can tend to come on strong with a half throttle acceleration, after the speed is stabilized, an addiitonal acceleration increase will bring on second power surge. Ultimately meaning that the bike can perform a wheelie at twenty five miles an hour or more.
8. Why should I buy Blata powered pocket bike over a less expensive bike. What's the difference?
   All bikes are not created equal. The most obvious of these differences can be seen in power. In comparison the Blata pocket bikes performance greatly outstrips the purchasing price difference between other bike brands. In the end, you get what you pay for.
9. How much does protection gear cost?
   Prices can vary depending on the level of protection that you desire as a rider. Regardless of this level, we highly recommend that all riders should wear a good helmet, gloves, riding jacket, riding pants or jeans with knee sliders and high top shoes. Most racers wear full racing suits, safety is vital to the health of both the driver and the sport, and should be a primary concern. Feel free to visit our apparel category for additional information and pricing details on riding apparel.
10. What additional protection gear does Mid-South Mini Moto recommend?
    When considering extra protection you must consider all areas that might be injured if you became separated from the bike at speeds. Usually this means helmet, gloves, riding jacket, riding pants or jeans with knee sliders and high top shoes. In addition to these basic items we recommend leather motorcycle riding apparel when racing or riding at high speeds. More than one person has suffered road rash in embarrassing spots when thrown off during a wheelie.
11. I understand that 2 cycle engines are high maintenance, are these engines dependable?
    A 2-cycle engine operates at higher speeds and higher temperatures than a 4-cycle engine. A water cooled option can help to regulate the temperature, and can potentially increase cylinder life. However the 4-stroke has a complicated valve system that is expensive to repair. In a bottom line assesment, a 2 stroke may need a cylinder replacement every couple of years with hard riding, but this is not very costly. We offer Polini replacement parts that are both inexpensive and easy to install, ultimately saving the customer money in the long run.
12. How hard is it to acquire additional parts and accessories?
    All parts and accessories can be obtained through most pocket bike vendors, such as Mid-South Mini Moto, which covers the entire spectrum of parts. We provide each and every part available for a bike, and can normally have them shipped the same day.
13. How do I mix Gas and Oil for my pocket bike?
    The standard Blata engine mixing ratio for Gas and Oil is 50 to 1, however some brands of pocket bikes using off brand engines may need a mixing ratio for Gas to Oil at 25 to 1. Be sure to read your owners manual before starting your pocket bike.  A new Blata engine should have a richer mixture of 40 to 1 for the first tank of fuel to help with proper break in. Do not use a mixture of less than 40 to 1 as it will be too rich and may foul the spark plug.
14. What oil is best to use in my pocket bike?
    We recommend any quality name brand 2 cycle oil (pre-mixed), which can be found any motorcycle / atv. store. Our personal brand that we use is Klotz Motorcycle Techniplate TC-W2, which can be purchased from our website.
15. Will my pocket bike operate on pump gas?
    Yes, however we recommend the use of fresh premium pump gas. Do not use any gas that has been stored for more than 2 weeks. A commonly used best practice is to mix only the nessecary fuel/oil for the duration of riding for that day or weekend.
16. I understand some engines are water-cooled, do they require antifreeze or just water?
    You should only use water in water-cooled engines. Insuring that they are drained during the winter season to avoid freezing.
17. Are pocket bike replacement parts expensive?
    No. Most pocket bike parts are reasonably priced and inexpensive to purchase.
18. Is it really as fun as it looks?
    No. It's MUCH more fun than it looks!

 

Two Stroke Engines
Two-stroke Engines are a marvel of engineering simplicity and efficiency.  They extract more hp per lb. than four stroke engines, and have far fewer moving parts. In fact, the Blata engine has only 3 major internal moving parts - piston, rod and crank.  In a two-stroke engine, the piston acts as the valve(s), opening and closing the intake and exhaust ports located on the cylinder walls. The two-stroke engine also fires each time the piston reaches the top of its travel (Top Dead Center, or TDC), unlike a four stroke engine which fires only every other time the piston reaches TDC. This doubling of the actual time the engine spends making power (as opposed to coasting through passive cycles) is largely responsible for the increased efficiency in the two-stroke design. As in a four-stroke design, a flywheel is employed to store inertia (rotational energy) to help push the reciprocating parts through their passive cycles.
Two stroke engines also are favored by motorcycle racers because of their characteristically strong powerband.  They are difficult to tame, but few things can compare to the thrill of riding a two-stroke motorcycle. While a four-stroke engine may pull fairly evenly from a relatively low RPM, two-stroke motors, due to their design, function best and most efficiently at a relatively narrower and higher RPM range than four-strokes. This is why they are often described as being "peaky". When they reach this point of maximum efficiency and power (the peak of the powerband) they provide a dramatic rush of power, and a kick-in-the-pants feel that has no equal in the four-stroke world. Because the focal point of this power peak can be effectively manipulated largely by changing the exhaust design and its volumetric displacement, a two-stroke engine is often described as going "on the pipe" when it reaches its power peak.
While all internal combustion engines can be described as merely "air pumps", this term is particularly accurate when used describe a two-stroke engine. There are four basic volumetric chambers in a crankcase reed valve induction two-stroke, such as the Blata engine. There is the intake airbox, the crankcase, the cylinder, and the exhaust's expansion chamber. These four volumes, when manipulated, can all effect the hp output, and the powerband's location in the RPM range. Each volume tends to act as an air "spring" and tuning each volume will affect the motor's performance, as the pulsations of the air within these tuned volumes actually can help to pump and draw air through the motor. Almost all modifications made to increase the hp of the stock motor will move this powerband upward in the RPM range.
Crankcase reed valve induction 2-strokes, as their name implies, inhale through the crankcase (the Dellorto and manifold are attached to the side of the crankcase) through a reed valve which acts as a one-way "doggy door-style" valve.
The crankcase is actually a dry sump and it contains no motor oil, so there's no oil to leak out. The crank and other internals are actually lubricated by the 2-cycle oil that you mix in with the gas at a ratio of 50:1 (use a good semi-synthetic 2-stroke racing oil available from any motorcycle dealer). The suspended oil provides lubrication as the air/fuel mixture flows past the internal parts.
When the piston goes up, it creates a vacuum in the crankcase, drawing air-fuel mixture from the Dellorto Carburetor and past the reed valve which gets pulled open by the vacuum signal, thus admitting air/fuel into the crankcase, filling it. When the piston reaches the very top of the cylinder, the spark plug fires, lighting the fuel mixture in the combustion chamber, which explodes and expands rapidly.  This pushes the piston back down, creating positive pressure in the crankcase, snapping the reed valve shut as it compresses the fresh air/fuel mixture that is now in the crankcase. The air/fuel mixture being compressed in the crankcase is known as pre-charge.
As the piston moves down, it exposes exhaust ports on the side of the cylinder, and the spent exhaust gasses begin to rush out of the ports. The exhaust is also ushered out by a rush of incoming fresh intake gasses, now entering via the intake ports located on the opposite side of the cylinder, which are the next ports to become uncovered as the piston continues downward.
When the intake ports open, they allow the pressurized "pre-charge" mixture to rapidly squirt from the crankcase into the top of the cylinder, through the transfer ports located along the sides of the cylinder that run down to the crankcase.
The piston then comes back up, closing off the ports; while below, the vacuum draws in more fuel through the crankcase, already beginning the next intake cycle. After the ports have been closed off by the rising piston, the mixture is further compressed by the piston rising until it reaches the top. The spark plug fires when the piston reaches the top, exploding the mixture and sending the piston down, and the whole process begins again.

 

Tires
The standard tires on the Chinese Pocket Bikes are the 5" tires. The optional "Big Wheels" which come on the 2WB models are commonly referred to as the 6" setup (these are actually 6.6" front and 6.1" rear).  These are tube-type tires, and wear very well offering some of the best available lean angles (some people actually prefer these tires to the newer 6.5" T-4 racing tires for this reason).  The 6" "Big Wheels" are just that - bigger WHEELS. The overall diameter is slightly larger, but only by an inch or so. The sidewalls are actually shorter than the 5" tires, and thus they squirm less, offering faster transient response and better handling, at the expense of some riding comfort. The 6"  "Big Wheels" for the 910 are the same tires that come standard on the 911 series bikes. Soft compound slicks are available for the 6" setup.
The new hot setup for racing is the 6.5" tubeless tires, which are available in a variety of compounds, including rain compound. These 6.5" tires are standard on the new race-prepared models, the 910 Steel, 911R and new GP/R models in the T-4 compound.  They are also available as an option on the standard 911 series bikes, and are only incrementally larger overall than the 6" tires. They are available in the following 4 compounds:
The PMT T-40 Tire compound tires (Durometer 60) offer awesome grip, great wear characteristics, and even decent wet performance (but not in standing water - they are slick), but they are a little more squat in profile and offer slightly less available lean angles than the 6" setup. This is why they are actually less favored by some of the larger riders who cannot "hang" off the bike as easily as the smaller riders, and need to be able to lean the bike over more.  ...But if you have the courage to hang off and keep the bike more upright and squarely on its tires, the T-40 Tires offer the better grip than the 6" and 5" setups.
The PMT T-41 Tire compound tires (Durometer 55) are a medium compound and offer a bit more grip, but at the expense of increased wear characteristics.
The PMT R Tire compound tires (Durometer 40) are primarily for rain use, and are available as slicks for hand grooving, or with a hand-cut rain tread pattern.  These tires offer the best possible rain performance, but are extremely soft and will get hot, oily, slippery, and go away very quickly if used in dry conditions.
The PMT B Tire compound slicks (Durometer 65) are a hard compound tire, and are generally not used in competition. These are favored for rental applications for their long wear characteristics.
The recommended tire pressures for the tube-type tires (as converted from BAR) are 17.5 lbs. front, 23.5 lbs. rear.  Adjust these numbers to suit your weight and riding style within the limits of the rated maximum inflation pressure stated on the sidewall (36 PSI MAX for the tubeless racing tires). You will find that heavier riders will need to adjust primarily the rear tire, because that is where the rider's weight mostly lies on a pocket bike.

 

Fuel
99.9% of all starting problems are caused by bad / old / improperly mixed gas. Never use oxygenated fuels or fuels that contain alcohol, as these can cause your bike to run lean, and destroy your motor. Racing fuels containing alcohol may also cause your bike to run lean, and are best avoided. Never use gas that has been in storage for even a short amount of time, and definitely don't use something from the can in the garage you bought for the lawn mower sometime last year.
Fuel should be mixed at 25:1 - fresh premium pump gas / high quality 2-stroke oil (Castrol Power 1 Racing RS G&S-T Product Number 010429).
The use of racing gas or octane booster is not required. Octane is a measurement of a fuel's ignition suppression characteristics.  Higher octane fuels will suppress "detonation", or "pre-ignition" (a.k.a. "ping", or "knock") by essentially being "harder to light", and actually burning more slowly.  This way, the high cylinder pressures of some racing engines will not spontaneously ignite the fuel at a point source other than the spark plug, which would result in colliding flame fronts, and detonation. Unless your motor has increased compression due to a modified cylinder head, or more ignition lead timing due to modifications to the ignition, the use of higher octane fuel will actually produce LESS power.

 

Spark Plug
Keeping a fresh spark plug in a 2-stroke motor is exceptionally important, and you should check your plug often.  It is very important to look carefully at the color of the plug as properly "reading" it can tell you a lot about the engine's state of tune.  The plug's ceramic insulator should ideally be a nice even tan color - this indicates complete combustion, and a proper fuel mixture.
A gray or white-ish plug indicates that the motor is running lean - this can result in engine damage! Clean and check your fuel system for obstruction, check your fuel mixture, check for loose intake manifold bolts and carburetor mounting leaks, failed case gaskets, loose case bolts and leaking crank seals. Anywhere your engine potentially could leak and suck fresh air can be the source of a lean condition.  Switch to a larger carburetor jet if necessary to correct the problem.   Failure to do so can result in engine seizure.

A blackened or oily plug indicates improper combustion resulting from a too-rich mixture, too much oil, or plug misfire.  First check your coil for a healthy spark. Use a fresh plug and ground the electrode to the engine while pulling the starter - the spark should be a healthy blue.  If so, install the fresh plug, and operate the bike normally for a few minutes, remove the new plug and "read" it.  If it still appears blackened or oily, the problem lies elsewhere.  A hotter plug in not recommended - make sure your fuel mix is correct, and consider a smaller jet only if the bike stumbles or sounds "full of snot" and doesn't run crisp.
Operating your bike a little too rich won't hurt it - but too lean is never good.  A little dirt in your carb could cause it to run lean, and you wouldn't even know why your bike was running so nice and crisp until it seized.  Because of the many factors that can affect the mixture, including the brand of gas you use, your oil ratio, and even air density, it is imperative that you check your plug often - it can save your motor.  Monitor your plug's color most attentively after any engine modifications to make sure re-jetting is not required to prevent a lean condition.
The 50cc kit, and the air-cooled models require the use of a longer thread plug.  Failure to use the longer thread plug will result in a very large reduction in performance, as the electrode will not extend into the combustion chamber sufficiently.  Use of the longer thread plug in a short thread cylinder head may result in the plug colliding with the piston - this will damage the motor.

We recommend the following NGK spark plugs:
Standard Air cooled 47/49cc Pocket Bikes NGK BM7A
Performance Air cooled 47/49cc Pocket Bikes with Performance Cylinders (cut Head) NGK CR7HIX Iridium
Competition use for water cooled Pocket Bikes (B1/B2 and Elite 13/14/15 Replicas)
NGK B9EGV (long thread)