Fitting the planetary hub to the bike. Fitting the planetary hub to the bike.
Today we are going to tell you about an interesting bike upgrade that one of our regular customers has planned. Recently he bought a Centurion Backfire Pro 200.29 bike from us and the owner decided to immediately transfer it to a planetary transmission, so to speak, “planetarize”. Shimano Nexus and Alfine components were selected for retrofitting. A planetary hub (for those who are not in the know) is a rear hub with a shifting mechanism inside the hub itself, while the whole gear shifting principle is somewhat reminiscent of a manual transmission in a car, with many gears, satellites, shafts, etc. The resource of such a bushing is enormous. up to 50,000 km, but it is also necessary to regularly maintain, change the oil, which ensures smooth and precise shifting. Another plus of such bushings, especially when driving around a city with a bunch of intersections, traffic lights, deer on the roads of pedestrian crossings, is that the gears can be changed while standing still, for example, from the sixth one, go straight to the first one! There are only two drawbacks. this is weight (1670 grams weighs Shimano Alfine S7001) and the fear of strong blows. But these disadvantages are more than offset by the convenience, comfort and unpretentiousness that this equipment gives. Actually, here is the “patient” is already hanging on the counter in our bike workshop “Mighty-Sport”:
Remove the rear wheel. with him, in fact, let’s start.
We throw off the rubber, rim tape, remove the cassette and brake disc. Next, we put the wheel for convenience on a stand for broaching and begin to spacing.
Further, after the wheel is unspotted, we go to measure the rim and sleeve to calculate the length of the new spokes:
knitting needles we need 290 mm on the left side and 288 mm on the right.
Now we take the planetary hub (and this is our Shimano Alfine S7001 for 8 speeds) and begin to wire it. Classic knitting, three crosses.
Then, when all the knitting needles are in place, we put them on the stand and start broaching, simultaneously removing the “egg” (vertical beating) and eights (horizontal beating).
The wheel with the new hub is now complete. We put on rubber, install a brake disc and a driven sprocket with 18 teeth. We remove the rear and front derailleurs from the bike, the chain and put the wheel, fix it with nuts.
Due to the fact that this type of bike has vertical dropouts, i.e. the chain tension was not adjusted by horizontal displacement of the hub, it was decided to install a Shimano Alfine ST-500 tensioner, which will compensate for the chain slack. It is installed, like a conventional switch, on the cock.
By placing washers of different thicknesses, which come with the tensioner, we achieve vertical alignment of the star on the bushing and tensioner rollers.
Next, go to the steering wheel. Remove the grips, brake levers and remove the now unnecessary Shimano Alivio 3×9 shifters. Instead, we put the Alfine shifter on the right!
Then we go to the system. remove the Shimano Alivio, remove the Hollowtech bottom bracket and begin to select the length of the new bottom bracket shaft. We have a Nexus system with one star and a square, respectively, you need to choose the length of the carriage shaft, at which the chain line will be as even as possible, without distortions. By selection, a carriage with a shaft length of 123 mm was determined, while the distance from the star to the feather remained about 5 mm. safe, you can put!
Installed the system. The silver color of the crankset matches the color of the bike perfectly!
We lay a cable with a shirt, put on a chain, having previously shortened it by several links and begin to set everything up!
The bike is ready and waiting for the owner!
Equipment removed from the bike in stock:
Bicycle planetary hub device
The planetary hub is a complex part of a bicycle that changes gears. It consists of many different types of gears. all of them are lubricated and protected by a sealed housing from dirt and dust. It is this complex design that provides a number of advantages of the planetary hub over classic gearshift mechanisms.
Features of bicycles with planetary hub
It is worth remembering that the considered part of a two-wheeled vehicle has a long service life; it does not require regular repairs and / or any additional maintenance. But the planetary hub is never installed on bicycles that are used for racing, mountain riding. Most bicycles are equipped with a planetary hub with seven or eight speeds, but there are also older models of this element of the vehicle. they are capable of “issuing” only 3 speeds.
Another feature of the part in question is that some of them can provide a bicycle with a reverse gear, which is actively used when equipping tricycles. If the bike owner prefers to ride his vehicle in the winter season, then it will be advisable to opt for a fixed gear planetary hub that has no free wheeling.
over, in the markets you can find a planetary hub with the ability to switch 14 speeds. whether or not to install such a powerful mechanism is a purely individual matter, but experts say that it is suitable only for those cyclists who travel long distances.
How the planetary hub works
It is possible to compare the principle of operation of the considered part of a bicycle with the gearbox of a car. inside the planetary hub there is a certain number of gears that have different gear ratios. And if we consider specifically the device of the planetary hub, then we need to focus on the following:
- the mechanism has a sun gear. it is located in the center of the device and is the axis of the wheel;
- the planetary sleeve has a carrier. this is a certain number of gears (they are called satellites), which are rigidly coupled with the sun gear;
- the mechanism contains a ring gear. it is located on the outside, has an internal gear train that engages it with the satellites.
Planetary hub on folding bikes
Many residents of large cities are trying to alleviate their fate of overcoming the road to work and other places. That is why folding bicycles are increasingly in demand among city dwellers. they are practical and convenient. But when acquiring this type of two-wheeled vehicle, experts recommend giving preference to those who have a planetary hub.
Why is it better to buy a folding bike with a planetary hub:
- you can change gears even when the bike comes to a complete stop. this is important in urban traffic jams and traffic lights;
- if you need to climb a hill, you do not need to simultaneously pedal and switch the speed. you can stop for just a fraction of a minute and set the required speed mode;
- the planetary hub is located in a sealed case, it reliably protects the mechanism from dirt, dust, snow, water. even when driving in urban conditions, it is not required to regularly service the part of the two-wheeled vehicle in question;
- the transmission of the planetary hub has an incredible service life. it is not subject to mechanical damage;
- such an option as “flying off” the chain while driving and the need to install it in place (and this is dirt and inconvenience) is simply excluded when using a folding bicycle with a planetary hub.
Some features of choosing a planetary hub
Firstly, it is worth remembering that the mechanism in question can be installed even on the most ordinary bicycle. this will allow you to modify your vehicle, and it is always interesting to experiment. This installation of the planetary hub will give you the opportunity to feel all the benefits of cycling with this part. perhaps such an assessment will be useful when choosing the next two-wheeled vehicle.
Installing a planetary hub on a classic bike is not difficult. you just need to abandon the roller brake.
Secondly, the bike part in question is constantly being improved and modified. recently, manufacturers have offered their customers a new 11-speed hub. It has certain advantages over 7 and 8 speed hubs:
- has a low weight. within one and a half kilograms;
- Great for installation on a two-wheeled vehicle, which is intended for both quiet walks and driving on bad roads;
- shifting gears is smoother and smoother.
Thirdly, experienced cyclists do not recommend immediately purchasing a vehicle with a powerful, modern planetary hub. a three-speed mechanism will be enough. The fact is that only an experienced cyclist will be able to feel all the speed changes, will be able to appreciate the ride on each of them. A beginner, or an inexperienced cyclist, will certainly be disappointed in the multi-speed planetary hub. some of its capabilities are generally advisable to use exclusively in hilly terrain.
That being said, the 3-speed planetary hub will fully meet the needs of the urban cyclist. why pay more?
The planetary hub is a rather expensive part, many simply do not risk installing it on already existing vehicles, or purchasing bicycles equipped with a similar mechanism. Nevertheless, it is worth listening to the characteristics of the planetary hub, which are given by consumers:
- regardless of the pedals (spinning / not spinning), you can switch the speed;
- the planetary hub is compact and reliable;
- gains speed quickly, dynamically and smoothly at the same time;
- there is no bulky mechanism that must be installed with the indispensable disassembly of at least half of the vehicle;
- the problem of the “flying” chain disappears;
- Significant energy savings are felt on long journeys on a planetary hub bike;
- the part in question can be operated for a long time without mandatory service.