Shimano gear adjustment: how to do it?

Shimano gear adjustment: how to do it?

There Shimano shift adjustment it is a very important operation that, however, many cyclists forget to do, thus preventing them from being able to fully enjoy the functionality of their bike and its effectiveness in traveling.

But what is the Shimano gearbox? And how can it be adjusted correctly?

The Shimano gearbox

Let's go in order. There Shimano is a Japanese company that produces articles for bicycles (but not only, since - for example - its products for sport fishing are quite well known). Founded 100 years ago, today it is a real point of reference in the mechanical components for mountain bikes and racing bicycles, producing in fact the best mechanical groups that make up these vehicles and, above all, the you change.

The adjustment of the gearbox

Having clarified the above, we can take a small step forward and try to understand what the Shimano shift adjustment, an operation that every cyclist should do, taking into account that it is also a rather simple operation, which does not require the use of specific tools and therefore anyone can try to do it quickly and efficiently.

Having said that, the first thing to do is certainly to check the support dropout and check that this support is perfectly straight. In fact, if the chain has the habit of jumping on all or almost all) the ratios, and maybe it yields especially on the upper part, then the problem may not derive from a bad adjustment, but from the wrong dropout. Worrying about this component is therefore the first step to take if you want to proceed with a correct one Shimano shift adjustment.

Now, take into account that there are special tools to check the correct alignment of the dropout, but that in any case if it is particularly bent, the misalignment of the dropout will also be visible to the naked eye. We advise you not to straighten the dropout yourself, because it is a very delicate component and could break if forced with your hands. Much better to take the bike to a trusted technician, who can intervene correctly with the appropriate tool.

The limit switch adjustment

After completing the brief verification above, you can start adjust the Shimano shifter starting with the adjustment of the limit switch, whose screws prevent the rear derailleur from making too much travel, causing the aforementioned fall of the chain. The screws of the upper or lower limit switch should actually be stressed as little as possible, considering that they should only be adjusted the first time ... by the manufacturer or by the shop that sold the vehicle.

However, it is logical that if the cyclist encounters frequent problems of yielding the chain upwards or downwards, it will also be necessary to intervene on these screws. The lower limit switch is usually located closest to the frame and is identified with the letter H (High Speed, harder relationship), while the one that adjusts the upper limit switch is identified with the letter L (Low Speed, more agile ratio).

Therefore, if the chain yields downwards, then the screw marked with the letter H must be screwed slightly, while if the chain falls upwards, then the screw identified by the letter L must be screwed in.

The adjustment of the cable tension

At this point it will be necessary to make a further effort, namely the checking and adjusting the correct cable tension, whose function is - moreover - to have a positive impact on the functionality of the gearbox.

Adjusting the tension of the cable is quite simple, considering that you can act directly using the adjusting screw, which is usually found on the gearbox itself. The adjustment must be made every time that the shifting is not very precise or that the chain shows signs of fatigue when going up or down.

More in detail, in the event that the chain fails to rise, or does so with extreme difficulty, then it means that the gear cable does not have sufficient tension. In this case, the good cyclist who wishes to be able to restore the correct functionality of the vehicle will only be able to intervene on the adjusting screw in an anti-clockwise manner, or by unscrewing it.

Bear in mind that in order to adjust the tension of the cable, many turns of the waist are not necessary, but only small adjustments. Sometimes in order to find the correct tension it is sufficient to act with small movements of the screw, even to the extent of a quarter of a turn, or half a turn. We therefore recommend proceeding with small steps, until you find the desired balance.

If, on the other hand, the chain does not go down or struggles to go down, it means that the cable is excessively tensioned. In this case it will be necessary to act by screwing the adjusting screw clockwise. Also in this case it is necessary to remember that it is good to proceed in small steps, avoiding making large movements that could instead make it more difficult to find the balance point for a correct cable tension.

In summary, if you want to give tension to the cable you have to unscrew the adjusting screw, while to remove tension from the cable you have to try to screw the adjusting screw.

Video: How To: Adjust Shimano Mechanical Road Front Derailleurs (January 2022).