1. This is what bikes look today No matter if it is the road bike, or MTB, they are great for what they are made for, but they are: Too complicated for a city ride, Too complicated to maintain because there are Too many parts, which leads that those bikes are Too much – expensive!

2. For city riding, some manufacturers made They are simple and cheap because they do not have derailleurs BUT You’ll be slow on the flat and you’ll be pushing your bike when you come to the slightest hill Single-Speed bikes

3. Some manufacturers, like Shimano, have made Gear Hub It has several speeds inside its hub But the friction gears produce is high, And the cost of the product exceeds the bike with common derailleurs.

4. So what is the solution, that will be cheap and can be used to convert any bike into bike with several speeds? If we could just use the simplicity of the single speed bike, but also have several speeds It would be perfect for city riding! We know that rear derailleur is the complicated one. Front derailleur and shifter are very simple and cheap. Why not use front derailleur and standard 3-cog crankset on the front, and one cog on the back?

5. The solution is in chain tensioner. Front derailleur switches from 44 to 32 to 22 tooth cogs, but something needs to make chain tight all the time, for all the options. There are many of chain tensioners out there, but none of them cannot make the chain tense for 22 tooth difference nor they could adjust to the various chain angles.

6. The chain is tense no matter which cog you use, 44t, 32t or 22t, It adjusts itself to make the chain strait and It keeps the chain on the cogs. This project would be chain tensioner made so that:

7. Here is how it would all look like (made from single-speed): Remove single speed crankset and add the one with 3 cogs Add front derailleur Add our tensioner

8. Who could benefit from this design? This is the public city bike in Amsterdam. They are single speed. They could be improved to 3-speed for a cost as little as 30$ per bike.

9. People who like simple ride with little or no maintenance, could convert their mountain bikes, road bikes or single-speed bikes, Bike rental companies, Manufacturers, if they choose to. Who else could benefit from this design?

10. How can you help and what will you get? If we gather 500$ donations, that would show that people like the idea, it will give us enough for a materials to build various models, and to experiment with parts, to find the best design. The design will be made public, It will be sent to whoever is in charge of public city bikes in cities that have them, And there will be a website describing how it works and how to make it.

11. Thanks for supporting the project. Lets make biking better!