The gears are the heart of every road bike. Only when the gear changes work crisply and without delay can the bike develop its true power and you can have maximum fun collecting kilometres. In view of the different shifting systems and manufacturers, however, it is not so easy to know which adjustments you need to make to set the gears on your road bike perfectly so that all gears slip and the chain does not jump over the sprockets. In this article, you will find various how-to videos showing the most important steps for mechanical and electronic road bike gears. We also go into the differences between Shimano gears and derailleur gears from SRAM or Campagnolo, for example. However, as the majority of road cyclists have Shimano drivetrains (from Shimano 105 to Ultegra and Dura-Ace) fitted to their bikes, we focus on the Japanese company's drivetrains when it comes to our tips for mechanics.
Content: You will find these topics and videos in this screwdriver article
- Adjusting the Shimano/SRAM/Campagnolo rear derailleur on a road bike
- Adjusting the Shimano derailleur on a road bike
- Adjusting the SRAM derailleur on a road bike
- Adjusting the Campagnolo derailleur on a road bike
- Setting the Shimano Di2 gears
- Setting the SRAM eTap AXS gearstick
- Campagnolo EPS gearstick adjustment
Adjusting the road bike rear derailleur: Instructions for Shimano, Campagnolo and SRAM
A grinding, rattling chain spoils every ride. The rear derailleur is often to blame. In the video, we show the perfect basic setting of a road bike derailleur (using a Shimano derailleur as an example). However, the basic settings - such as tension, limiting the stops and chain wrap angle - of mechanical road bike drivetrains all work according to the same principle, regardless of whether the rear derailleur is a Shimano Ultegra or the rear derailleur is from a SRAM Force groupset.
Common problems with road bike drivetrains & how to fix them
Chain rattles - what to do?
If the chain rattles in all gears and the road bike drivetrain does not shift smoothly, change the tension on the rear derailleur adjustment screw . If you want the chain to climb better on large sprockets, increase the tension by turning anti-clockwise. If the chain is reluctant to climb onto smaller sprockets, reduce the tension (clockwise). If the adjustment range is not sufficient, tighten the tension on the clamping screw. If the adjustment fails, check that the derailleur hanger is tight and not bent. The so-called B-screw adjusts the distance to the sprocket (wrap angle of the chain); with the chain on the largest sprocket, the distance to the derailleur pulley should be about five millimetres.
Sluggish road bike gears - what to do?
If the chain reacts sluggishly in both directions, lubricate the derailleur joints first. If this does not help, the cause may be stiff cables, which you should replace.
Extreme gears shifting incorrectly - what to do?
If the chain shifts poorly or not at all onto the largest or smallest sprocket, the rear derailleur may be limited too early by the stop screws. Turn the screws anti-clockwise to extend the swivelling range. The screw for the smallest sprocket is labelled "H" (high = highest gear), the screw for the largest sprocket is labelled L (low = lowest gear). Do not unscrew the screws too far; the chain must not move beyond the largest or smallest sprocket.
Chain jumps over sprocket - what to do?
If the chain jumps over the sprockets under load, the chain and/or sprockets are probably worn. Check the wear and replace the parts if necessary (>> To the instructions).
The derailleur hanger is essential for good shifting function, but is sensitive: In the event of a fall, it bends easily or even breaks off. The problem is that every frame has a different one and retailers rarely have the right one in stock. It is therefore advisable to keep a spare in stock, even when travelling or at a training camp. Order one directly from the bike manufacturer; other sources include the websites Schaltauge.de or Schaltaugen.info
Tool tip
If the derailleur hanger is bent, a wheel (for quick-release axles) can be used as an emergency tool: The axle threads usually fit into the thread of the rear derailleur. Use the rim of the installed rear wheel as a guide and carefully bend the derailleur hanger until both wheels are parallel.
Adjusting the road bike derailleur
Modern derailleurs on road bike drivetrains are complex structures and sensitive when it comes to installation and adjustment. We show you the most important steps for Shimano derailleurs, SRAM drivetrains and Campagnolo groupsets when the chainring gets stuck.
Adjusting the Shimano derailleur: The video guide
Campagnolo derailleur adjustment: The video guide
Adjusting the SRAM derailleur: The video guide
Road bike gears: Correcting the derailleur position
If the chain grinds on the outer front derailleur plate, either the tension must be increased or the swivelling range must be extended outwards using the stop screw (marked "H"). If it grinds on the inside, either the tension is too high or the inner stop screw (labelled "L") limits the pivoting range. In modern front derailleurs, the stop bolts are often hidden in the parallelogram; in older models, they are usually on the top.
Tip for front derailleur adjustment with Shimano derailleurs
Modern Shimano front derailleurs have a screw with which you can change the tension. With all other front derailleurs, the tension must be changed at the clamping screw . To do this, shift to the smallest chainring to relieve the tension on the cable.
Prevent chain drops
If the chain is thrown inwards or outwards from the chainrings, you must readjust the stop bolts. Shift to the highest gear (large chainring/smallest sprocket) or lowest gear (small chainring/largest sprocket) and adjust the respective stop bolt so that the guide plate is not rubbing against the chain - there should be no more than one millimetre of space. You can take the strain off stiff bolts by pushing the derailleur slightly to one side.
Parts tip: Front derailleur support for Shimano and SRAM
The front derailleurs of the latest Shimano shifting generations (including Di2) and the electric SRAM eTap shifting systems must be supported on the frame to ensure proper functioning. Shimano derailleurs have a support screw for this purpose, which is screwed to the frame after adjustment; a suitable metal plate must be glued to carbon frames. For the electric SRAM front derailleurs, there are various wedges that are clamped between the frame and front derailleur - make sure you use a suitable one!
Adjusting electronic road bike gears: Shimano Di2, SRAM eTap and Campagnolo EPS
Electronic drivetrains are being fitted to more and more road bikes - especially the popular Shimano Di2 groupsets or eTap AXS drivetrains from SRAM. The basic settings are easy to make with just a few button presses, as shown in the video below. The basic settings work in exactly the same way as with mechanical drivetrains, for example limiting the pivoting range using the two stop screws (high and low) or the adjustment screw for the wrap. The big difference is the fine adjustment, which can otherwise be made via the tension. This works differently for the electronic road bike shifters from Shimano, SRAM and Campagnolo.
Setting the Shimano Di2 gears
With Shimano's Di2 drivetrains, you have to switch to the adjustment mode for fine adjustment via the control unit. Depending on the road bike model, the control unit can be located in the frame, at the end of the handlebars or on the stem. To access the setting mode, press the button on the control unit for a few seconds until the red LED lights up. You can then use the shift buttons to shift up and down (right-hand shift lever) to position the rear derailleur precisely under the sprockets. To save the setting and exit the setting mode, press the button on the control unit for several seconds until both LEDs flash briefly and then go out.
To adjust the front derailleur, the Shimano Di2 drivetrain only has a 2-millimetre screw, which is used to set the distance from the outer guide plate to the chain to around 0.5 millimetres in the highest gear.
Setting the SRAM eTap AXS gearstick
With the electric, wireless SRAM eTap AXS drivetrain, the electronic fine adjustment only works on the rear derailleur; the front derailleur is only adjusted using the stop screws. Fine adjustment is carried out by pressing and holding the mode button on the inside of the shift lever and simultaneously actuating the shift lever. The SRAM eTap rear derailleur then adjusts itself in fine steps in the respective direction (to the right or left, depending on whether the adjustment is made on the right or left shift lever).
Campagnolo EPS gearstick adjustment
To access the Campagnolo EPS shifting adjustment mode, press the mode button on the inside of the brake lever for about six seconds until a purple LED lights up on the control unit. You can then use the two shift buttons to position the Campagnolo rear derailleur up or down under the sprocket. A special feature of Campagnolo electric drivetrains is that the electronic fine adjustment can also be carried out on the front derailleur. This is done using the mode button and the shift buttons on the left shift lever. To exit the adjustment mode, you must briefly press the respective mode button once.
Our video guide with TOUR lab manager Christoph Allwang shows exactly how the adjustment of the Shimano, Campagnolo and SRAM gears differs.
If the electronic shifting system on the road bike is set up correctly, it should work permanently. This is because the shift cables do not stretch as they do with mechanical shifting systems.
Jens Klötzer
Editor
