How to remove the paint colour of my bike?

There are few Paint Remover sprays available in the market that you can buy online or offline. You can use it to remove the old paint from the bike by following the instruction given in the instruction leaflet provided by the product brand.

Few of the Paint Remover brands are as below;

Cosmos Paint Remover
Dr Wood Paint Remover
TetraClean Paint Remover
NeoLux
Worison

To re-paint the bike, it has to be dismantle the parts and paint the required one to avoid unprofessional painting.

There are many chemicals that will remove paints. Basically, they are two types.
1. Solvent-based paint removers. These paint removers will have some organic solvents that are useful to get the paint dissolved and get removed from the part. Some of the solvents that are used in these preparations are methylene chloride, acetone, toluene, methanol, N-methyl-pyrrolidone etc,
2. Caustic based paint removers. These paint removers will have some alkalies in them. Sodium hydroxide ammonia hydroxide and calcium hydroxide are some of the chemicals that are used in these preparations.
But it is always better to go for solvent-based paint removers.
The following are the paint removers.
A Methylene Chloride (MC)
This paint remover removes the paint layer by layer. It will not make the paint soluble but delaminates, This paint remover is available in two forms namely gel and liquid form. The gel version is to be used to remove the primary paint and the liquid form is used to finally clean the surface.
B. N-Methyl-Pyrrolidone (NMP)
These paint removers will have no health risks. But slow in action. These are very effective in removing paints from very old surfaces. They are good to remove multiple layers of paint. But they are costly. They may cost 3 to 5 times more than normal paint removers.
C. Acetone, Methanol and Toluene (ATM)
They remove paints by liquefying them layer by layer. They are flammable. They are less costly but should not be used in closed rooms and sufficient ventilation should be there.

To remove the earlier paint from the bike is not going to be an easy job as the metal paint bonds well with the metal and makes a good cohesion. The traditional method is to scrape it rigorously till it is removed and naked metal emerges out.
Nowadays many other methods are available which are as follows -
1. Using chemicals - There are some chemicals like acetone and ammonia which are widely used to remove paint from the metallic surfaces. These chemicals loosen the paints from the metal surface through chemical reactions. One has to be careful if one wants to use them as one will have to use mask and gloves while doing that.
2. Using baking soda - If the painted metal surface is kept in contact with baking soda solution in hot water for a long time about an hour or so then paint becomes lose and can be scraped in easier ways. This method is basically for metal pieces which can be dipped in solution. But by wetting the bike body with this solution will also be helpful in peeling out the paint.
3. Steaming method - By steaming hot steam for about an hour the paint starts chipping out from the metal surface. One would require a steam blower for this.
4. Acidic solutions - Using acidic solutions also loosens the paint from the metal surface. Some of the commonly used acidic mediums are concentric nitric acid, hydrochloric acid, and phosphoric acid.
5. Spray nozzle scraper - These are scrapers fitted with small pores for chemical drops to be sprinkled at the scrapping site. These are efficient scrappers for removing paint.

One last point in this context is that there are some RTO rules and regulations for changing the colour of the vehicle and one should take care about that as per the regulations in that state where one is living.