How to make a pit bike out of a bicycle

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This summer we crossed paths with my former student from the Automotive and Tractor Faculty of SURGU. he came to sign the economic part of the diploma.

I am doing here a project of a promising wheeled vehicle.

And I immediately suggested: Let’s measure it!

Homemade Dirt Bike

And it really turned out that he really needed the performance characteristics to defend the diploma.

But first, I rode his first two-wheeler: Swift Indiana, a mini moped made of water pipes and a motorcycle-style bike frame from The Fastest Indian movie. A year ago, Daniel came on it for a couple and in a 30-degree cold, and in a terrible slush. A real bike obsession. Therefore, I had deep respect for Danil, as for any person who is irrevocably devoted to his work: completely and completely!

And if the Fast Indian was for the soul, then here is the second street bike (Danil wanted the frame to look stylish) and the installed Chinese motor with a power of 2 hp was a diploma project Development of a small-sized vehicle

The control is arranged like this: on the left is the clutch handle, and on the right is the gas handle. The engine can only be started using the pedals. from the pusher. And then, smoothly working the clutch and gas, turn on the motor assistance. In fact, there are three main modes of operation, great: you can just pedal without turning on the engine and the clutch. while controlling Black Work (as Danil called the bike) it will ride like a normal bike. an option is pedaling assist when the throttle is moderate and the engine is helping to pedal. Or you can just drive a gasoline engine at an average speed of 50 km / h. Speaking of numbers!

We took measurements using Driftbox 4 attempts in each direction to avoid the influence of wind and slope of the road (the arithmetic mean was calculated). Maximum speed. 56.39 km / h. Acceleration to 50 km / h. 12.55 seconds. Braking. by vehicle level: from 50 km / h to 0 in total. 21.72 meters Fuel consumption 1.2 liters per 100 km Tank 2 liters.

My biggest fear was that the 2hp motor, transmission and tank would ruin the bike’s lightness. But no. due to the relatively light frame, the increase of 8 kg is not felt and the big one is felt as an ordinary great. You can quickly start on it, and jump, jump on curbs. Or you can start and drive the motor. Keeps cruising 50 km / h easily. I fired up like this)))

I have the street itself Norco Ride. I like it great. but the comfortable limit for me is 7-10 km. And here you can drive and jump and get to the place. And indeed, use it as an alternative means of transportation. The budget of such a vehicle on a used ear frame will be about 15,000-20,000 rubles.

I understand that it is dangerous on such roads on public roads, and on sidewalks too (especially on busy streets). This is the problem of Russia. on the road the cyclist will be perceived as an interfering booger.

Now in September in Russia, the words-calls for a bicycle sound especially funny. When at least two months of cold, piercing rain, melting snow, wet feet and numb hands await us ahead of us, talk about cycling seems to be somehow unnecessary and out of touch with reality. Although I ride my bike to the garage even in winter (about 1 km). it’s just faster than walking.

What is included

In order to turn a bike into an electric bike, you need the following main components (they are included in every kit):

  • wheel motor. This is the heart of the electric bike, the electric motor. You just change one wheel for another;
  • accumulator battery;
  • battery fasteners, wires;
  • control panel, or console.

In order for disappointments not to be endless, you need to know that a sufficiently fast and long ride is possible only with a power of about 1000 W, that is, 1 kW. If you decide on the price, then for a wheel motor with a kilowatt engine, on average, you will have to pay 20 thousand rubles.

An electric bike can be made with a larger or smaller battery. So, a battery with a capacity of 18 Ah will cost 30 thousand rubles.

Therefore, it is not recommended to buy cheap electronic kits that can only drag for a short time on a flat road. They develop a power of 250. 35- W and can be considered children’s.

The ideal but expensive option is a 2000 W motor.

I Bought the MOST Expensive Electric Dirtbike EVER

A cargo tricycle powered by car batteries can be considered quite an interesting and budget option. As you know, one such battery has a capacity of 55 Ah and can give very good results. It is not difficult to make such an electric bike with your own hands, it is much more difficult to find a reliable cargo bike with a trolley for placing batteries. In addition, a bike with support for more than two wheels can be more comfortable for fishing, for cycling tourism within reach of an outlet.

However, chargers have already been created that can power a bicycle electric motor from solar panels, charging it during the descent, and also charge it at halts using miniature steam turbine generators powered by fire energy.

Thinking about the future

It is also important to consider whether the model of your choice can be fitted to your bike. It will be a shame if you don’t succeed in remaking your bike and you need to buy a new one.

Will you be able to do this work on your own, or do you need to look for a qualified bicycle mechanic with knowledge of electrical engineering, which is a very large deficit?

Determine exactly where the battery will be placed, estimate its dimensions so that the homemade e-bike is comfortable.

Fat bike assembly recommendations

When selecting components and assembling a wide-wheel bicycle with your own hands, please note that:

  • Common framesets use 2 rear brakes. i.e. requires 2 rear brake adapters IS-PM.
  • Sometimes non-offset forks are manufactured using a special 135mm front hub and use a front brake adapter. Therefore, before buying, you need to carefully read the description.
  • The bulging of the rim tape through the holes in the rim of the fat bike is not only a visual effect, but also protection against scrolling the tube in the tire.
  • A common problem with off-set fatbikes is the chain hitting the tires in minimum gears.
  • The assembly of offset wheels must be done carefully so as not to accidentally fold the rim.
  • It is pointless to use light spokes when assembling a fat bike. in order to really reduce weight, you need to purchase light rubber and light rims.

As for the fenders, they are also produced for wide-wheel bicycles. If you are wondering how to make cheap wings for a fat bike with your own hands, you can cut a regular wing in half and fix an aluminum or plastic plate in the middle.

All-road bike

What is a fat bike in essence? This is the same familiar bike. rigid, hardtail, full suspension. but on very wide tires. The rubber width of 4-5 inches (10-12 centimeters) gives an incredibly large contact patch between the wheel and the surface. But this is not the only thing about fat bikes. These tires can be inflated with a very small volume of air. in some cases, only 0.2 atmospheres. For comparison: the pressure in the wheels of a mountain bike is usually 3-4 atmospheres (at least this is recommended by the tire manufacturers).

READ  How to adjust the hand brakes on a bicycle

Soft, wide rubber with good tread is what allows this bike to ride where no other will pass. Yes, on such wheels. just think about it!. even conquered the South Pole. The fat bike is the all-terrain vehicle in the bicycle world. And this is his most important dignity.

Fat bike or winter bike

Experienced cyclists and lovers of constant sports training have long been using bicycles all year round, regardless of the weather. In one of our articles, we already wrote that in winter you can ride a bike without any particular difficulties and problems, it is enough to follow simple rules.

How to assemble a fat bike at no extra cost?

Assembling a wide-wheel bicycle will cost at least 40-50 thousand rubles, and this is in the presence of the lion’s share of spare parts. In order to save money, you can:

  • Collect a fatbike on a Surly Pugsley frame;
  • use components from old bicycles, for example, used cranks;
  • take the simplest spokes and assemble the wheels with your own hands;
  • use the cheapest rubber. 27TPI;
  • purchase rims of the Weinmann DHL80 class and make an offset on them.
make, bike, bicycle

In order to rationally invest funds and guarantee to get the desired result, it is better to use the services of professionals. If you want to assemble an electric fat bike with your own hands, but do not have the skills and experience in this area, do not put expensive experiments. Contact the VoltBikes workshop. and we will make all your wishes come true at affordable prices!

Read in our previous article about what kind of motor-wheels are.

You are fat! 5 facts about fat bikes these bikes love and hate

Another attempt to reinvent the bicycle. By the way, images of prototypes of bicycles on wide wheels were found back in the thirties of the XX century. people so wanted to come up with something fresh for a seemingly very traditional and simple vehicle. What for? Well, of course! What could be better than plowing snowdrifts on a bike somewhere far from existing trails or conquering a sand dune on two wheels? Today we are talking about one of the most unusual types of serial bicycles. the fat bike.

How to install a gasoline engine on a bicycle with your own hands

From this step-by-step instruction, you will learn how to install a gasoline engine on a regular bicycle, that is, make a motorcycle out of a bicycle that can travel more than a hundred kilometers on one liter of gasoline.

Installing the second chain and sprocket.

The rear sprocket has a 35.9mm center hole and mounts perpendicular to the hub axle on the left side. Spin the rear wheel and check if it dangles. this may cause the chain to fly off.

The convex side of the rear sprocket on the hub should be facing the wheel.

Cut a spacer out of the rubber to protect the space around the spokes and axle. Attach it with nine bolts to the steel lock plate that comes with the sprocket.

On some bikes without a foot brake, it may be necessary to install an insulator on both sides of the sprocket to align the chain.

The rear sprocket must match to the nearest 0.5 cm with the sprocket on the engine. If necessary, shorten the chain to the required length. To remove excess links, you need a tool such as a chain wringer. Ideally, the tension of both chains (pedal chain and motor chain) should be approximately the same.

Remove the protective panel from the rear left side of the motor.

The motor comes with a sprocket that matches the chain included in the kit. If you are not satisfied with the supplied standard bike chain and would like to replace it with a biker chain such as the 415 HD, then you should also replace the sprocket on the motor. Instead of a narrow sprocket, buy a sprocket with wider teeth.

Use a wrench and spark plug to turn the engine crankshaft sprocket to pull the chain around it.

To achieve the desired chain length, measure it and remove excess links. The length of the drive chain is correct if the top of the chain can be deflected by 0.25. 0.5 inches and at the same time stretched its lower part.

Reinstall the chain lock and guard plate on the engine.

The chain tension is adjusted by shifting the rear wheel. If you can achieve the same tension on both chains, then you will not be able to install the idler roller. If you did not manage to pull the chain to the motor as tightly as the chain to the pedals, then you will have to install an idler roller.

Install the supplied chain guard by attaching it to the motor and frame tube.

Tank.

Attach a fuel drain cock to the tank. Use Teflon tape to seal the threaded joint.

Connect the fuel line to the tank and carburetor. Use a quality fuel line such as GoodYear. The included transparent plastic fuel line becomes hard and stiff over time.

Since the engine is a two-stroke engine, you have to mix engine oil into the gasoline. Initially, until you use up the first four liters of gasoline, you should maintain a ratio of 18.20 parts of gasoline to one part of oil. In the future, this ratio can be increased to 20. 25 to one.

Clutch, throttle, emergency switch and spark plug.

Place the clutch lever on the handlebar and thread the cable into the engine lever. When the clutch lever is depressed, the motor is disengaged from the rear wheel so that it can start. Cut off the remainder of the cable so that you do not injure yourself on the very sharp end while pedaling. Make sure you tighten the screw well so that it doesn’t get lost.

Remove the old handle from the bike and use the allen wrench to install the choke on the right side of the bike. Pull the cable from the throttle to the carburetor so that slight resistance is felt when pulling on the cable.

Connect the red wire from the throttle to the frame, and the black wire to the white wire that comes from the motor. When the emergency stop switch is pressed, the engine should stall, not just stop.

The engine should have a white spark plug on the lid of the black box with the wires coming out of it. Connect the black and white wire to the black, blue wire to the blue.

What is needed to create a homemade bike with a gasoline engine.

To make a homemade motorcycle out of a bicycle, we need:

  • bicycle;
  • screwdriver;
  • two clamps;
  • Grubee 66cc motor;
  • petrol;
  • a hammer;
  • tank;
  • throttle;
  • emergency switch;
  • muffler;
  • star;
  • chain;
  • squeezing the chain;
  • fuel line;
  • butter;
  • warm workplace.

Installing a gasoline engine on a bicycle.

Mount the motor to the bike frame above the bottom bracket using cable ties.

The motor is mounted above the carriage on two frame tubes simultaneously. If the motor mounts do not reach the frame tubes, then brackets will be required. To achieve the ideal position of the motor, first place it on the seat tube as low as possible and then attach it to the down tube.

How to start the engine.

Before starting the engine of a homemade motorcycle, press the fuel button and open the carburetor. Pull the clutch all the way down and start pedaling until you pick up at least a low speed. Then release and turn the throttle. Pedal until the engine starts. Then, with the help of the throttle, you can simply adjust the speed of the bike.

Thinking about the future

It is also important to consider whether the model of your choice can be fitted to your bike. It will be a shame if you don’t succeed in remaking your bike and you need to buy a new one.

Will you be able to do this work on your own, or do you need to look for a qualified bicycle mechanic with knowledge of electrical engineering, which is a very large deficit?

READ  How much pressure should be in bicycle tires

Determine exactly where the battery will be placed, estimate its dimensions so that the homemade e-bike is comfortable.

How to convert a bicycle into an e-bike

  • What do you need it for?
  • Determining the power
  • Thinking about the future
  • What is included

Sooner or later, every biker becomes corrupt for a short time, and, having wound several tens of kilometers in a day, begins to faintly dream of the means of small mechanization of an ordinary bicycle. However, after rest, these immodest desires usually pass, and the bicycle again becomes an object of desire. Nevertheless, the idea of ​​making an electric bike with your own hands is very popular and is becoming more widespread every year. We will tell you more about how to do it.

From the realm of dreams: In the photo, an extreme six-kilowatt bike, developing from a standstill at a speed of 60 km / h in three seconds. The peak current is 100 amperes on lithium-iron-phosphate batteries At the request of the manufacturers, it maintains a speed of about 60 km / h for 40 km. Magicians live here: http://www.voltbikes.ru/blog/projects/E-bike-3000W-6000W-lifepo4/

Our tasks are much more modest. Immediately, we will limit ourselves to the fact that we do not mean the production of an electric bike from scratch, but we will talk about how to choose and install a special conversion kit on your favorite bike. After this alteration, the electric bike will be able to help you out in a difficult situation.

Central motor (set)

One of the most powerful options is the Bafang G510 frame mount center motor conversion kit. Available engine power. 1 kW. The voltage for the battery is 48 volts. Suitable for all types of e-bikes, including MTB, cargo-cargo bike.

Determining the power

  • the power of the engine, which is located around the wheel hub (the speed and traction qualities of an electric bike depend on it);
  • battery capacity. The autonomous riding time and the weight of additional equipment depend on it, which usually does not exceed 10 kilograms.

Of course, additional data can be included in the assessment list, for example, the number of battery recharges (resource), the time spent on a full charge, and many other indicators.

Much depends on the rider’s weight. A teenager weighing 50 kg and an overweight man weighing 125 kg apparently need different sets.

Electric motor kits for bicycle carriage

The inexpensive bottom bracket / center motor kit. BAFANG BBS01B (250W approved) is a quick way to convert your bike. The powerful BAFANG BBS02B kit (750 W) will cost a little more. Both options have a good weight / price / power ratio and will work in most cases. There is an even cheaper model. this is a simple DIT motor that is suitable for beginners.

E-bike frames

The heart of any bike is the frame. If you are remodeling your existing bike, then one of the kits above will suffice. And if you are assembling from scratch, or a deep alteration involves replacing the bike frame, then turn your attention to ready-made hybrid frames with an already installed motor. The frame for MTB E-BIKE 29ER is available here with an integrated 500 W central motor (maximum torque 120 Nm). If you want to make assembly easier, choose modern components, namely carbon parts. One carbon frame gives the bike a measurable weight reduction.

What is included

In order to turn a bike into an electric bike, you need the following main components (they are included in every kit):

  • wheel motor. This is the heart of the electric bike, the electric motor. You just change one wheel for another;
  • accumulator battery;
  • battery fasteners, wires;
  • control panel, or console.

In order for disappointments not to be endless, you need to know that a sufficiently fast and long ride is possible only with a power of about 1000 W, that is, 1 kW. If you decide on the price, then for a wheel motor with a kilowatt engine, on average, you will have to pay 20 thousand rubles.

An electric bike can be made with a larger or smaller battery. So, a battery with a capacity of 18 Ah will cost 30 thousand rubles.

Therefore, it is not recommended to buy cheap electronic kits that can only drag for a short time on a flat road. They develop a power of 250. 35- W and can be considered children’s.

The ideal but expensive option is a 2000 W motor.

A cargo tricycle powered by car batteries can be considered quite an interesting and budget option. As you know, one such battery has a capacity of 55 Ah and can give very good results. It is not difficult to make such an electric bike with your own hands, it is much more difficult to find a reliable cargo bike with a trolley for placing batteries. In addition, a bike with support for more than two wheels can be more comfortable for fishing, for cycling tourism within reach of an outlet.

However, chargers have already been created that can power a bicycle electric motor from solar panels, charging it during the descent, and also charge it at halts using miniature steam turbine generators powered by fire energy.

make, bike, bicycle

How to get PTS on a pit bike officially?

Any transport with an engine capacity of over 50 cubic meters when moving on public roads must have a vehicle title. Initially, a pitbike is a sports equipment and a technical passport is not provided for it; upon purchase, a check and an agreement are issued, which states that motor vehicles are not intended for driving on a public road.

You can go through government certification, which will check the purchase documents, technical specifications and whether the bike meets safety standards (i.e., whether it has all the necessary electronic, light and sound devices).

The examination procedure is paid, plus you will have to invest heavily in the installation of all equipment. However, after that you can absolutely not be afraid of problems with the law and meeting with traffic cops.

From how old can you ride a pit bike?

Due to its small size and lightness, the pit bike is very popular among teenagers. Often, in general, it is called children’s and, with appropriate equipment, even 5-year-old children are allowed to ride.

Children of any age can ride a pitbike on suburban tracks, the main thing is that parents do not forget to monitor the safety of the child. The only thing is that motorcycles with a volume of more than 125 cubic meters are more suitable for teenagers over 14 years old.

Only children over 16 years old can ride around the city on a PIT bike up to 50 cubic meters (if it has the relevant documents), if they have a license to drive a moped. On a bike of a larger volume, they can go on public roads, only after 18 years and with an open motorcycle category in the rights.

To get the right to drive a mini-motorcycle, you must unlearn at a driving school according to the general rules and pass exams at the traffic police.

What documents are needed for a pit bike?

As a result, it turns out that for city driving you need:

  • Rights of category B or A (depending on engine size).
  • Technical device passport (PTS) or service book.
  • Insurance (for a pit bike 125 cubes and more)

By the way, many are interested in whether it is possible to ride a pit bike together? Theoretically, it is possible for two people of light weight. In practice, this is very dangerous, the PIT bike has no footpegs for the passenger, and he risks getting his foot in the wheel.

What else can be done?

It is not entirely legal to bypass the ban on city driving, but some have been driving this way for several years. Your pit bike may well pass for a Chinese moped. Its small dimensions and engine dimensions are quite consistent with the size of a moped. For this you need:

  • Find on the engine where the volume is knocked out and wipe it with a drill. It is necessary to completely smooth the surface so that not even a trace of the inscription remains. You can also erase the markings on the motor just in case.
  • Find a service book from any Chinese moped, in which the fields will not be filled in and there will be a stamp from the seller’s company. And also there must be a check with the prescribed amount of purchase.
  • Make the pitbike look like a moped: install road tires, hang the lights on the handlebars and place a brake light under the tail. Remember to always turn them on.
READ  Fitting the front fender on a forward bike

Do I need a pit bike license?

A pit-bike is a small motorcycle that looks more like a child’s. When buying a pit bike, many owners have a question: is it possible to ride a pit bike around the city and do they need a license or not.

Initially, this is sports equipment that is used for motorcycle racing and, according to the law, riding a pit bike on public roads in the original configuration is impossible, since:

  • For them, they initially do not make technical passports, which are necessary for registration with the traffic police.
  • No necessary electronic equipment: speedometer, side lights, turn signals, etc.

Therefore, riding a PIT bike around the city, even on the sidewalk or sidewalk, is initially illegal, and if you only ride it through fields and mountains, you can do without a license. Provided that you will deliver it to the countryside in the back of a truck or trailer.

However, if you decide to try to arrange your motorcycle for city driving (which is a rather complicated and expensive task, we will consider below how you can do this), you will still need your license. over, the receipt is similar to conventional motorcycles.

make, bike, bicycle

What are the rights to a pit bike?

The answer to this question depends on the size of the engine:

  • If the volume of the engine does not exceed 50 cu. cm, and the maximum speed is up to 50 km / h, then a car license or category M license will do.
  • If the engine displacement of the pit bike is 125 cubic meters or more, then motorcycle license of category A is required.

But remember that even if you have a license, motor vehicles can still be taken to the impoundment parking lot if there is no technical passport and lighting equipment. In summer, motorcycles, similar to pit-bikes, are stopped by traffic cops especially actively.

In summer, motorcycles that look like a pit bike are stopped by traffic cops especially actively.

How to behave on the road in the city?

If in this way you legalized your driving around the city on a pit bike, then remember that representatives of the law can still stop and doubt your vehicle. Stay on the fact that this is a moped so weird, what the Chinese do not do.

  • Be sure to wear a helmet, so the traffic police will have fewer reasons to stop.
  • Observe traffic rules: keep to the far right lane, do not drive drunk, do not drive on red, etc.
  • Try not to drive too much, especially when driving past traffic cops, ride at a speed of about 50 km / h.

Driving outside the city

From the point of view of legislation, there is no prospect of driving a pit bike either in the fields or on country roads. The latter are considered the territory adjacent to the DOP, and movement along them is regulated by traffic rules. And the rules, as you know, driving unregistered vehicles without a passport and license is not provided.

As for the fields, where no one expects to see an inspector, you also cannot feel completely safe on them. It is possible that on the road closest to the place where you are driving, there will be a patrol-guard service car. If the representatives of the law have a suspicion that you even drive on the field without a license and documents for a pit bike, they can easily check this fact. At least, there were precedents in judicial practice. In addition, it is possible that your actions and sounds of the motorcycle will annoy the villagers, and they will not be too lazy to call the outfit.

Of course, you can try to prove that your pit bike is a sports equipment, which means it is not subject to registration. It can be argued that you rolled it on the field manually, without moving along the DOP, that you skated exclusively for the sake of training. However, in this aspect, another problem will arise. The fact is that, according to the law, driving on a plowed field is in itself an offense and is punishable by a fine.

Features of riding a pit bike: legislative nuances

Before figuring out whether documents are needed for a pit bike, if it is positioned as a sports equipment, consider what this vehicle is. The miniature motorcycle was first used in America for racing competitions. Both the personnel serving the track and the pilots themselves moved on it. He replaced the bike, as, thanks to the built-in motor, he demonstrated high speed indicators.

Destruction of myths

In Russia, driving on public roads (DOP) at the legislative level is regulated by order of the Ministry of Internal Affairs of the Russian Federation 001 On the procedure for registering vehicles, issued on November 24, 2008. According to the document, in order to travel to the DOP, you must have a vehicle passport (PTS) and a driver’s license. It doesn’t matter if you travel by car or miniature motorcycle.

Any owner of a pit bike in this case will begin to appeal by the fact that a PTS is not issued when buying sports equipment. The traffic police have their own opinion on this matter. Yes, and the legislation says: if a pit bike is defined as a sports equipment, then it is intended exclusively for training and competition held in specially designated areas. There is no difference between public roads, whether they are in the city, outside or in the village. If you are stopped by an inspector without a title and a license, this will be a pretext for proceedings.

The main question for mini-motorcycle owners in Russia

A little time passed, and the field of use of the pit bike expanded. Already at the end of the 1960s, it went on a wide sale, they began to acquire it for entertainment and household needs. In some sports competitions, for example, in motocross, it is the main equipment, it is actively used for tourism.

Mini-motorcycles are popular in Russia, but they are also bought because they imply a certain legislative loyalty in operation. However, to the question whether the rights to a pit bike are needed, if it is sports equipment, the traffic police inspectors, as a rule, have an affirmative answer. At the very least, the lack of a driver’s license threatens at least with penalties.

How to get out of the situation

Since a pit bike is a sports equipment, it is prohibited to move on it along the DOP. If an inspector stops you while doing this, a fine is guaranteed. Most often, they are accused of driving an unregistered vehicle and driving it without a license. There is a high probability that the pit bike will be sent to the impound until the circumstances are clarified. Often it comes to court, and this already means that it will be very difficult to return the motorcycle. In addition, you will have to pay for the work of the tow truck and the stay of the pit bike in the parking lot. The prospects are sad, but there are some things you can do:

  • Get a certificate. Do not be lazy, visit the courses where you will be given the rights of the corresponding category. When meeting with an inspector, you will no longer face a fine for driving a vehicle without a certificate.
  • Take with you the sales contract, invoice, check and other documents confirming the purchase of the vehicle legally.
  • Prepare a sports bike passport. You can order it in the motorcycle federations of Russia (MFR, NRMF).

In most cases, the inspector, seeing the correct paperwork and a polite, confident driver, is unlikely to find fault. The complete absence of the above documents is a likely path to the impoundment with all the consequences.

There is another way that adventurous pit bike owners turn to. The fact is that vehicles with an engine volume of less than 50 cm³ do not require a TCP. In this case, a driver’s license and motorcycle purchase papers are sufficient. Knowing this, some bikers underestimate the cubic capacity in the documents. However, such tricks do not always work. If a forgery is revealed, it will be expensive.