Step by step guide; Replacing a Shimano Nexus Inter 3 shift lever
This guide deals with replacing a Nexus 3 shift lever, inner and outer cable, and click box (also known as a bell crank unit).
For the most part, replacing a shift lever from a brand like Sturmey Archer or SRAM is pretty similar to replacing a Shimano shift lever.
Mounting the gear cable to the hub is done differently, however, and this guide only applies to Shimano shift levers.
When you get a new Shimano shift lever or shifter, parts like the cables, click box and cable ferrules and cable crimp ends are often included.
The various Shimano Nexus Inter 3 shift levers are all interchangeable.
Step 1 : Removing the shift lever, cables and click box
1
2
3
Remove the handlebar grip on the right side of the handlebars. (See Replacing bicycle grips) (1)
Undo the Shimano Nexus 3 shifter clamp, using a small allen key. Slide the shift lever off of the handlebars. (2)
Undo the bolt on the back of the click box using a 10 mm spanner.
Step 2 : Removing the shift lever, cables and click box
1
2
3
Undo the black cover at the bottom of the click box, using a small Phillips screwdriver. (1)
Now you can loosen the click box cable by undoing the cable clamp, using an 8mm spanner. (2)
After doing this, you can remove the click box.
Pull the inner and outer cable from the frame and then separate the outer cable and inner cable from each other.
The shifter cap can be removed with a small Phillips screwdriver. (3)
Step 3 : Removing the shift lever, cables and click box
1
2
3
Put the shift lever in first gear, so you can pull out the inner cable. (1, 2, 3)
Step 4 : Mounting the shift lever, cables and click box
1
2
3
Your new shift lever usually comes with a pre-mounted inner cable. (1) If you only need to replace your inner cable, all you have to do is follow the directions in step 5.
Slide the shift lever back onto the handlebars, leaving room for the handlebar grip. Once the grip is fastened in the right place, the shift lever can be secured against it. (2)
Remove the cover, using a Phillips screwdriver, and make sure the shift lever is in first gear. (3)
Step 5 : Mounting the inner cable
1
2
3
Take the inner cable through the shift lever, until the cable comes out through the cable opening. (1, 2)
Check whether the cable is run over the cable guide correctly to avoid damaging the inner cable. (3)
Step 6 : Cutting the outer cable to the right length
1
2
3
The outer cable can be cut to the right length in one of two ways: either by putting the new outer cable next to the old one and then cutting the new cable to the same length, or simply by mounting the new outer cable onto the frame and then cutting it as you see fit.
Pull the cable through the shift lever fully, until it can go no further. (1)
Measure the right length for the outer cable, for example by using the length of the old outer cable for reference. The cable should be long enough that you can still easily turn the handlebars. (2)
The remainder of the outer cable will stick out at the back of the click box. (3)
Step 7 : Cutting the outer cable to the right length
1
2
3
Put the click box on the rear axle so you can cut the outer cable to the right length. (1, 2)
Mount the cable ferrule on the outer cable. (3)
The click box can now be removed, for the inner cable to be mounted.
Step 8 : Mounting the click box
1
2
3
Pull the inner cable through the outer cable and make sure the outer cable sits snug against the shift lever for correct adjustment.
Pull the outer cable through the click box and the cable clamp bolt inside the click box. (1)
Push the clamp for the inner cable out and pull the inner cable taut, then tighten the cable clamp bolt. (2)
Mount the click box on the axle and check whether the gears work. (3)
Step 9 : Mounting the click box
1
2
3
Remove the click box again and cut the inner cable to a length of between 5mm and 10mm, using the cable cutter. (1)
Mount the black cover over the click box using your Phillips screwdriver.
The click box can now be mounted back onto the axle. (2)
To adjust the shift lever, you will first need to put it in second gear. (3)
Step 10 : Adjusting the gears
1
2
3
The Shimano Nexus 3 can be fine-tuned in two ways. The push rod has a thin red stripe as well as a thicker yellow stripe. If the click box position is slightly off, because of an added axle ring, the yellow indicator stripe may also deviate slightly from its usual position. In this case, the red indicator stripe is leading.
The gear can be adjusted using the adjuster screw on the click box. (1)
The yellow indicator stripe should be positioned exactly between the two white stripes. (3)
Twist the adjuster screw to the left to turn the indicator inwards.
Twist the adjuster screw to the right to turn the indicator outwards.
Step 11 : Adjusting the gears
1
2
The red indicator stripe is leading when you’re adjusting the gear. In second gear, this stripe should be level with the end of the axle. (2)
Twist the adjuster screw to the left to turn the indicator inwards.
Twist the adjuster screw to the right to turn the indicator outwards.
en
Nederlands
Deutsch
Español
Français
Italiano
Dansk
Suomi
Norsk
Polski
Português
Svenska
中文
Česky
日本語
Pусский
한국어
Română
Step 1 : Removing the shift lever, cables and click box
