SHIMANO NEXUS 3-SPEED HUB - SG-3C41 - Service Manual - vol.1 - Disassembly and Assembly of the Inter-3 hub

Oct 29, 2026

Upload by Ophelia

Service instructions for the SHIMANO NEXUS 3-speed hub model SG-3C41, covering volume 1 procedures to disassemble and assemble the Inter-3 hub. The manual emphasizes that unit parts should not be disassembled individually, and that replacement should be done as whole internal assemblies or unit parts. It provides step-by-step removal and installation operations for components such as the hub shell, brake arm unit, brake shoe unit, carrier and ring gear units, pawls, lock nuts, cones with dust seals, and ball retainers. It also specifies required tools and internal hub grease, and includes multiple safety and alignment notes, including thread protection and correct setting directions.

LanguageEnglish

CategoryTechnology

FormatPDF

Pages12

Reading Time30 min

AccessFree to download

Disassembly of the Inter-3 hub

Disassembly steps and precautions

Component removal (brake arm, hub shell, carrier, ring gear)

Further disassembly (pawls, ball retainers, driver/axle unit)

Assembly of the Inter-3 hub

Assembly steps and installation notes

Grease application and setting direction checks

t SHIMANO NEXUS 3-SPEED HUB SG-3C41 SERVICE MANUAL vol.1 | Disassembly of the Inter-3 hub | | | | | | --- | --- | --- | --- | --- | | | | | | | | SG-3C41
Note:
Unit parts should never be disassembled. If they are, problems may result.
When replacing parts, replace the whole internal assembly or unit part.
Tools
Note:
Before carrying out disassembly, have ready the hub spanners (TL-7S20/ TL-HS20) and internal hub grease. | | | Screwdriver (Left)
TL-7S20 (Center)
Hub spanners
Part No. 130 9890 17mm x 22mm(2 pcs.)
TL-HS20 (Right) Hub spanners
Part No. 320 9001 15mm / 17mm (2 pcs.) | | | 1. Hold the two bevelled surfaces
of the hub axle on the brake arm side in a vice and remove the dust cap with a screwdriver.
| | | | Screwdriver
Vice
Note:
Do not damage the threads of the hub axle. | 2. Turn the brake arm unit upside down and hold the two bevelled surfaces of the hub axle on the sprocket side in a vice. Note: Do not damage the threads of the hub axle. Remove the left hand lock nut from the hub axle, and then remove the stop nut. TL-7S20 Left hand lock nut Stop nut | 3. | Remove the brake arm unit. | | Brake arm unit | | --- | --- | --- | --- | | 4. | Remove the hub shell. | | Hub shell
Internal assembly | | | Now it can be replaced | Part No. | | | | with the new internal | [SG-3C41] | | | | assembly. | Y-35U 98010 (Axle Length 168 mm) | | | | Internal assembly for quick disassembly and assembly |
Y-33R 98020 (Axle Length 175 mm)
Y-35U 98020 (Axle Length 178 mm)
[SG-3C41-DX]
Y-35U 98010 (Axle Length 168 mm) | | | | | Y-33R 98020 (Axle Length 175 mm) | | | 5. Remove the brake shoe unit. | | | Brake shoe unit | | 6. | Remove the stop ring with a screwdriver.
At this time, the stop ring come off with great force. Be careful of the safety using cloth and so on. | | Screwdriver
Stop ring (9mm dia.) | | | | --- | --- | --- | --- | --- | --- | | 7. | Remove the carrier unit and the ring gear unit at the sametime while turning the ring gear unit slightly to the left and right.
Carrier unit
Ring gear unit | | After removing them at the sametime, remove the carrier unit from the ring gear unit. | | | | | | | | | Carrier unit
Ring gear unit | | 8. |
Remove ball retainer K while pressing in pawl A-1 and pawl Con the driver unit a screwdriver.
Pawl A-1 ball retainer K
| | Note:
Be careful not to bend ball retainer K.
Screwdriver
Pawl C | | | 9. Turn the axle unit with driver unit upside down and hold the two bevelled surfaces of the axle in a vice. Note: Do not damage the threads of the hub axle. Remove the right hand lock nut and the right hand cone with dust seal from the hub axle. TL-HS20 Axle unit with driver unit Right hand lock nut Right hand cone with dust seal | 10. Remove ball retainer J from the driver unit. | | Ball retainer J
Driver unit | | --- | --- | --- | | 11. While pushing the two pawls

C on the driver unit with your fingers, remove the driver unit.
Note:
Be careful not to let pawl pin B fall out.

Pawl C
Pawl A-1
| | Driver unit
While pushing pawls C with your fingers
Note:
Do not disassemble the axle unit, otherwise it may cause problems with gear shifting. | This completes the disassembly of the Inter-3 hub. Assembly of the Inter-3 hub | 1. | | | | | Note:
Do not damage the threads of the hub axle. | | | | --- | --- | --- | --- | --- | --- | --- | --- | | 2. | While pushing the two pawls C on the driver unit with your fingers, place the driver unit onto the axle unit.
Note:
Be careful not to let pawl pin B fall out. | | | | Driver unit
While pushing pawls C with your fingers
GREASE (Y-041 20800)
| | | | | | Pawl C
Pawl A-1 | | | | | | | 3. | Place ball retainer J onto the driver unit.
Ball retainer J
Axle unit with driver unit | | | | Note:

FAQs

What is the key rule when replacing parts in the SG-3C41 hub?

Unit parts should never be disassembled; replace the whole internal assembly or the entire unit part to prevent problems.

Which tools and consumables are required before disassembly?

Have the hub spanners (TL-7S20/TL-HS20) and internal hub grease ready before starting disassembly.

What precautions are given to avoid damage during the work?

Do not damage the threads of the hub axle, do not bend ball retainers (e.g., K), and take care to prevent parts such as pawl pin B from falling out.

Oct 29, 2026

Upload by Ophelia