How tight should the rear derailleur cable be?

Make sure the derailleur mounting bolt is tight, or shifting will be sloppy no matter how well adjusted the cable is. This usually takes a 5-millimeter hex wrench. If you can't find the exact specification, 5 to 8Nm is the typical range for this bolt.

Should my derailleur cable be tight?

Holding the cable tightly so it can't slip, pull up with the pliers to remove all slack in the cable and hold it like this as you tighten the anchor bolt to secure the cable in place. It should now be tight enough so that when shifted onto the large chainring, there's no rubbing.

How tight should your gear cable be?

You need to pull it pretty tight before clamping it to the derailleur. Probably as tight as you can. Usually I find that's still not tight enough, so I screw the barrel adjuster down all the way before putting the cable in and then open it up until the tension is correct.

How do you adjust the tension on a rear derailleur?

Adjust the cable tension

Turning the adjuster anticlockwise increases tension on the cable, bringing the derailleur closer to the wheel. Clockwise decreases the tension, moving it back towards the frame. If the chain seems hesitant to shift up, increase the cable tension by turning the barrel adjuster anticlockwise.

How do I fix my bike cable stretch?

Thankfully this is a pretty simple one! Cable stretch is remedied by ADDING tension the lines affected. This is what those barrel adjusters on your bike are for! You or your mechanic can simple wind those up in order to add tension and restore braking feel and shifting performance. Voila!

Do derailleur springs wear out?

That said, derailleur springs will lose tension overtime, and pivots will get sloppier. Shifters can wear out too (if you ride enough), and most cannot be serviced back to health. But before you go sinking money into these more expensive components, best try a new cable/housing or get a second opinion.

How do you calculate tension in a cable?

The tension in a given strand of string or rope is a result of the forces pulling on the rope from either end. As a reminder, force = mass × acceleration.
...
Account for rotational acceleration.

1. F_c = m × v²/r.
2. F_c = 10 × 2²/1.5.
3. F_c =10 × 2.67 = 26.7 Newtons.
4. So, our the total tension would be 98 + 26.7 = 124.7 Newtons.

What do the screws do on a rear derailleur?

Derailleurs are fitted with limit screws that stop the derailleur from moving too far inward or too far outward. If you look closely as the derailleur moves, you can see the limit screws stopping the derailleur at each end of it's travel.

How do you loosen a derailleur cable?

Remove the Derailleur Cable

Shift into the small cog (or as close as you can get if it won't fully engage). Loosen the cable anchor bolt and disengage the cable from the derailleur. If the cable end prevents complete removal, just make sure the bolt is loose enough to allow the derailleur to move free of the cable.

How do you install a derailleur cable?

Shift into a small ring on the cassette. With your thumb, push the body of the derailleur toward the large cog. The top pulley should align with the largest cog in the cassette. If the pulley moves past the largest cog toward the spokes, turn the limit screw marked “L” clockwise to tighten.

Is my front derailleur cable too tight?

Test shift of front derailleur to all three front chain rings. If the derailleur rubs in the largest front chainring, double check H-limit screw and inner wire tension, which may be too loose. If chain is slow to shift to smallest chainring, double check L-limit screw and inner wire tension, which may be too tight.

How do I adjust my bike cables?

Here's how to do it:

1. Step 1: Shift into the smallest gear. I also like to drop my cable tension as low as possible. ...
2. Step 2: Adjust the high limit screw, usually marked with an “H”. ...
3. Step 3: Tension the cable properly. ...
4. Step 4: Carefully shift up into the largest gear. ...
5. Step 5: Fine adjustments.

What is the barrel adjuster on a bike?

Barrel adjusters are small cups that have a hole in the bottom, and are screwed into different points around your bike. They are usually located by your brake levers, brake calipers, gear levers, and derailleurs. They work by increasing the amount of distance an inner cable will travel.

What are the three screws on a rear derailleur?

On most derailleurs there are three limit screws: the upper limit, Lower limit, and B-limit. The upper limit screw sets the maximum distance the derailleur can shift in high gears. The lower limit screw sets the maximum distance the derailleur can shift in the lower gears.

Why is my derailleur hitting my spokes?

Often, the derailleur hits the spokes when its hanger is bent following a heavy hit. If that's not the case, it could be due to wobbly spokes, misadjusted limit screws, or incorrect cable tension.

What is the L and H on a bike?

Many shifters are marked in some way, often numbered or with an 'H' for the high gear and an 'L' for the low gear. The '1' or 'L' refers to the innermost chainring (closest to the bike).

What is cable tension?

Tensioning is a construction technique that stresses a concrete column to reduce the traction load it is submitted to. Tensioning consists of a procedure where the cable, stays or steel bar throughout a concrete column is pulled to pre-tension it (in the plant) or post-tension it (on site).

Is tension equal to weight?

The pulling force that acts along a stretched flexible connector, such as a rope or cable, is called tension, T. When a rope supports the weight of an object that is at rest, the tension in the rope is equal to the weight of the object: T = mg.

Can tension negative?

Tension can either be positive or negative depending on where the coordinate axes are placed. Regardless of the upward direction being taken as positive or negative, the force balance equation for both gives the same result.

How long will a rear derailleur last?

Derailleurs will last almost indefinitely. The jockey wheels will wear out in time (tens of thousands of km) but the rest of the mechanism shouldn't see significant wear. It could be that the spring will break at some point due to material fatigue, but that is also a relatively easy to replace part on most derailleurs.

How do I know if my rear derailleur is worn out?

Worn Derailleur

All derailleurs wear out at some point. Check for wear by pulling laterally on the lower cage. Compare this movement in the linkage of a new derailleur. Sloppy pivot and linkages will produce inconsistent shifting, and the only solution is a new derailleur.