Headset bearing size chart and model finder: dimensions and seating angles
Filter the recorded headset-bearing models by inside diameter, outside diameter, width and source-listed angle. Keep the complete designation: similarly named ACB bearings can differ in outside diameter, width or seating geometry. Results are component references, not a bicycle fitment approval.
On this page13 sections ⌄
Search the source-backed bearing size table
Catalogue dimensions, not measurements of a worn part. The table remains readable without JavaScript; with JavaScript, filters apply as you type. The source snapshot and unresolved discrepancies are retained in the private audit.
Dimensions are exact catalogue values in millimetres. Matching a row identifies a reference, not approval to install it. On small screens, scroll the table sideways.
| Manufacturer / model | d (mm) | D (mm) | B (mm) | Listed angle(s) | Construction / record notes |
|---|---|---|---|---|---|
| Enduro ACB Mini 276442 BO | 14.2 | 25 | 6.5 | 45×45° | Angular-contact; black-oxide steel; designation follows page title |
| Enduro ACB Mini 276442 SS | 14.2 | 25 | 6.5 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 6804 BO | 19 | 30 | 6.5 | 45×45° | Angular-contact; black-oxide steel; alias not approved |
| Enduro ACB 6805 CC | 27.15 | 38 | 6.5 | 36×45° | Angular-contact; black-oxide steel |
| Enduro ACB 4545 1125T SS | 30.15 | 41 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 3645 CC BO | 30.2 | 41 | 6.5 | 36×45° | Angular-contact; black-oxide steel |
| Enduro ACB 3645 CC SXD | 30.2 | 41 | 6.5 | 36×45° | Angular-contact; SXD construction variant |
| Enduro ACB 4545 136 SS | 32.75 | 41.75 | 6 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 3645 1125 BO | 30.5 | 41.8 | 6.3 | 36×45° | Angular-contact; black-oxide steel |
| Enduro ACB 3645 1125 SS | 30.5 | 41.8 | 6.3 | 36×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 1125 BO | 30.5 | 41.8 | 6.5 | 45×45° | Angular-contact; black-oxide steel |
| Enduro ACB 4545 1125 SS | 30.5 | 41.8 | 6.5 | 45×45° | Angular-contact; 440C stainless |
| Enduro S7806 LLB 2RS-36 | 30 | 42 | 7 | 36° ID only | Angular-contact; 440C stainless; one-sided chamfer stated |
| Enduro 6806 LLB OSID | 30.2 | 42 | 7 | 45° ID only | Steel; one-sided chamfer specification |
| Enduro ACB 3645 3544 SS | 35 | 44 | 5.5 | 36×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 S8551 BO | 36.8 | 45.8 | 6.5 | 45×45° | Angular-contact; black-oxide steel |
| Enduro ACB 4545 125T SS | 34.1 | 46 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 125L SS | 34.1 | 46.8 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 137 SS | 37 | 46.85 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 68025 CC | 33.15 | 46.9 | 6.5 | 36×45° | Angular-contact; black-oxide steel; alias not approved |
| Enduro 6807 LLB | 35 | 47 | 7 | Not stated | Radial; ABEC 3; C3; LLB |
| Enduro ACB 3645 3748 BO | 37 | 48 | 6.5 | 36×45° | Angular-contact; black-oxide steel |
| Enduro ACB 6806 CC BO | 37 | 49 | 6.5 | 36×45° | Angular-contact; black-oxide steel |
| Enduro ACB 6806 CC SS | 37 | 49 | 6.5 | 36×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 1375 SS | 37 | 49 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 405495 SS | 40.5 | 49.5 | 6.5 | 45×45° | Angular-contact; 440C stainless |
| Enduro B 543 2RS AC | 39.6875 | 50.8 | 7.14375 | Not stated | Angular-contact steel; exact conversion from inch source |
| Enduro B 543 LLB SS | 39.6875 | 50.8 | 7.14375 | Not stated | 440C stainless; exact conversion from inch source |
| Enduro ACB 6808 SS / 290413 | 40 | 51 | 6.5 | 36×36° | Angular-contact; 440C stainless; 51 mm OD |
| Enduro ACB 4545 150 SSM | 40 | 51.8 | 7 | 45×45° | Angular-contact; 440C stainless; 51.8 mm OD |
| Enduro ACB 6808 CC BO | 40 | 52 | 6.5 | 36×45° | Angular-contact; black-oxide steel |
| Enduro ACB 6808 CC SS | 40 | 52 | 6.5 | 36×45° | Angular-contact; 440C stainless |
| Enduro ACB 6808 CC SXD | 40 | 52 | 6.5 | 36×45° | Angular-contact; SXD variant; verify full material specification |
| Enduro ACB 4545 150 BO | 40 | 52 | 7 | 45×45° | Angular-contact; black-oxide steel |
| Enduro ACB 4545 150 SS | 40 | 52 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro ACB 4545 4252 SS | 42 | 52 | 7 | 45×45° | Angular-contact; 440C stainless |
| Enduro S68808 SP | 40 | 53 | 7 | 45×45° | 440C stainless; confirm the complete model |
| Enduro ACB 3645 5062 SS | 50 | 62 | 8 | 36×45° | Angular-contact; 440C stainless |
| Enduro 6712 2RS-45 | 60 | 75 | 7 | 45° ID only | Radial; ABEC 3; C3; one-sided chamfer |
No loaded reference matches all selected fields. Clear a dimension or inspect the original marking. A missing result does not prove the bearing does not exist.
36×45, 45×45 and 36×36: keep the geometry separate
Use the maker's convention for the angle order and compare the mating surfaces. An ID-chamfer-only radial reference must not be relabelled as a 36×45 or 45×45 cartridge. These are interface details; the table does not derive internal rolling-contact geometry from a product name.
On smaller screens, scroll the table sideways to read all columns.
| Example reference | Recorded geometry | Why the suffix matters |
|---|---|---|
| Enduro ACB 6808 CC SS | 40×52×6.5 mm; 36×45° | The CC record has a 52 mm outside diameter |
| Enduro ACB 6808 SS | 40×51×6.5 mm; 36×36° | A similar name does not preserve outside diameter or the angle pair |
| Enduro S7806 LLB 2RS-36 | 30×42×7 mm; 36° inner chamfer only | A one-sided chamfer statement is not a published pair of seat angles |
Why a 1-inch, 1 1/8-inch or 1.5-inch label is not d×D×B
A headset's nominal fork size and the cartridge's physical inside diameter answer different questions. For example, the published ACB 6805 CC record is 27.15×38×6.5 mm. Do not replace those dimensions with 25.4 mm merely because the headset family is described as one inch.
The finder does not round 41.8 to 42 or convert a cup code such as ZS44 into a 44 mm bearing. Use the SHIS reference for frame/fork interfaces and this table for the particular bearing.
Steel, black oxide, stainless and ceramic: choose the complete specification
The reference prioritises fit, specified construction and service conditions. It does not rank 'best headset bearings' from price, a material name or a claimed warranty. A corrosion-resistant bearing still needs compatible seats, seals, adjustment and inspection.
On smaller screens, scroll the table sideways to read all columns.
| Construction or label | Useful question | Not established by the label |
|---|---|---|
| Black-oxide-treated steel | Does the exact record specify the required geometry and protection? | Unlimited corrosion resistance |
| 440C stainless steel | Do the rings, balls, seals and lubricant suit the assembly? | Interchangeability with a steel bearing of another angle |
| XD15-based construction | Which ring and ball materials are actually listed for this model? | That every component is ceramic or the same stainless alloy |
| Ceramic or hybrid | What is ceramic, and what remains steel? | Correct dimensions, lower installed friction or longer life in every headset |
| Sealed cartridge | What are the seal design and service instructions? | An inspection-free or permanently waterproof assembly |
Missing and conflicting specifications are not filled by guesswork
Only reviewed geometry is available in the finder. A source page with incompatible dimensions, a missing width or contradictory product identity is retained for verification rather than silently corrected. Load ratings are outside this chart's scope.
Bike-specific searches such as a named frame model or year require an application record as well as a bearing record. No result here establishes that every generation of a Canyon, Trek, Specialized, Cannondale or other model uses the same parts.
Compare upper and lower headset bearing kits
Choose two exact Acros kit references to see their source-listed size sequences, angles and construction fields together. Similar names or the same lower bearing do not prove that the upper bearing is interchangeable.
Compare the upper and lower bearings as a pair. Matching one diameter does not identify a complete headset kit.
19 source-listed references. Open a reference to inspect its specifications.
These are manufacturer-listed references, not a guarantee of fit. Confirm the exact frame version, original headset, fork and revision. No result means no verified match in this dataset—not that no part exists.
300.52.1153-AMis52/is52 bearing set a01Bearing kit
- Steerer tube
- 1 1/4" / 1.25"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact ball bearing
- 42 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact ball bearing
- 40 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel ball bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.02.104-AMIS42/IS52 Headset Bearing KitBearing kit
- Upper inner diamter (ID)
- 42 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer upper
- 1 1/8" lower: 1.5"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 30.1 x 41.8 x 8 - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 40 x 52 x 7 - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.02.122-AMIS49.5/IS52 Headset Bearing KitBearing kit
- Upper inner diamter (ID)
- 49,5 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer upper
- 1 1/8" lower: 1.5" or 1 1/8"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 40,5 × 49,5 × 6,5 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 40 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.920is52/is52 bearing kit - integrated cable routingBearing kit
- Press-fit diameter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube top
- 1 1/8" (28.6 mm), bottom: 1.5" (40 mm)Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 42 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 40 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.920R1is52/is52 bearing kit - integrated cable routingBearing kit
- Press-fit diameter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube top
- 1 1/8" (28.6 mm), bottom: 1.5" (40 mm)Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 42 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 40 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Some current source pages disagree on model or condition labels for this reference. Only identical complete associations are included here; conflicting records are withheld.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.921is52/is52 bearing kit a02,integrated cable routingBearing kit
- Press-fit diameter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube top
- 1 1/8" (28.6 mm), bottom: 1.5" (40 mm)Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 42 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 40 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.922-AMis52/is60-lagerset, integrated cable routingBearing kit
- Press-fit diameter top (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 60 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube top
- 1 1/8" (28.6 mm), bottom: 1.8" (45.8 mm)Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 42 × 52 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 46 × 60 × 8 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.950is44/is48-bearingset (ai-70) for canyonBearing kit
- Press-fit diameter top (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 48 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- 1 1/4"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper deep-groove bearing
- 35 × 44 × 5 mm - -/-Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular-contact bearing
- 37 × 48 × 7 mm - 36°/-Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.951R1is44/is44-bearingset for canyonBearing kit
- Press-fit diameter top (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- 1 1/4"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper deep-groove bearing
- 35×44×5.5 mm - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular-contact bearing
- 33×44×6 mm - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.952-AMis41/is41-bearingset a01Bearing kit
- Press-fit diameter top (ID)
- 41 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 41 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- 1 1/8"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 30.1 × 41 × 6.5 mm - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 30.1 × 41 × 6.5 mm - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.953is44/is52-bearingset a01Bearing kit
- Press-fit diameter top (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- top 1 1/4", bottom 1.5"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 44 × 35 × 5.5 mm - 36°/36°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 52 × 40 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Bearings made of steel/stainless steelThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.954-AMis44/is52-bearingset a02Bearing kit
- Press-fit diameter top (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- top 1 1/4", bottom 1.5"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 44 × 35 × 5.5 mm - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 52 × 40 × 7 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Bearings made of steel/stainless steelThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.955-AMis41/is41-bearingset a02Bearing kit
- Press-fit diameter top (ID)
- 41 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 41 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- 1 1/8"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 41 × 30.1 × 6.5 mm - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 41 × 30.1 × 6.5 mm - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Bearings made of steel/stainless steelThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.956-AMis48/is48-bearingset, canyonBearing kit
- Press-fit diameter top (ID)
- 48 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Press-fit diameter bottom (ID)
- 48 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer tube
- 1 1/4"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 39 × 48 × 6 mm - 36°/36°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 37 × 48 × 7 mm - 36°/36°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
56.52.957-AMis44/is44-lagerset a01Bearing kit
- Upper inner diamter (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 44 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer
- Canyon CIUFork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 35 x 44 x 5,5 - 36°/36°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 33 x 44 x 6 - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- Steel ball bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
68.02.901is41/is52-bearingsetBearing kit
- Upper inner diamter (ID)
- 41 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer Upper
- 1 1/8" Lower: 1.5"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 41 x 30.1 x 6.5 - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 40 x 52 x 7 - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
69.52.951is42/is47-bearingsetBearing kit
- Upper inner diamter (ID)
- 42 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 47 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer upper
- 1 1/8" lower: 1 1/4"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 41.8 x 30.1 x 8 - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 46.8 x 34 x 7 - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
69.52.952R1is41/is47-bearingsetBearing kit
- Upper inner diamter (ID)
- 41 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 47 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer upper
- 1 1/8" lower: 1 1/4"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 41 x 30.1 x 6.5 - 36°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 47 x 35 x 7 - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
69.52.953is52/is47-bearingsetBearing kit
- Upper inner diamter (ID)
- 52 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Lower inner diamter (ID)
- 47 mmHeadset/frame interface field. The source ID label is not the inside diameter of the loose bearing cartridge.
- Steerer upper
- 1 1/8" lower: 1 1/4"Fork or crown-race interface notation. A nominal inch label is not the cartridge bore; do not convert one into the other.
- Upper angular contact bearing
- 42 x 52 x 7 - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Lower angular contact bearing
- 34 x 46.8 x 7 - 45°/45°Size and angle sequence retained as published. Source ordering varies; this is not automatically d×D×B or an interchange approval.
- Additional source specification
- stainless steel bearingsThis is a source-listed component or assembly field; do not substitute it for a different interface.
Acros public product and headset-finder records · Checked 2026-10-04. The checking date is not a manufacturer revision date.
No recorded reference matches all filters. Clear a filter, inspect the component marking, or measure both bearing seats. Do not choose the nearest result as a substitute.
How to read this reference
- Size sequences are preserved in the manufacturer’s order. Do not assume every sequence means bore × outside diameter × width.
- A headset’s ID, press-fit diameter, steerer size or crown-race interface is not automatically a loose cartridge bearing dimension.
- An unspecified angle (–/–) is unknown, not zero. A steering-stop angle describes steering travel, not a bearing seat.
- A 7 mm source height does not establish a 6.95 mm specification. A revision or suffix remains part of the reference.
- This selected dataset is not a complete Acros catalogue. Accessories, configurable families and conflicting associations are not silently treated as bearing kits.
Sources are used to verify the facts. BearingScope provides the organisation and interpretation; it does not reproduce an official fitment approval or installation manual.
What the evidence can — and cannot — tell you
| Observation or context | Interpretation to consider | Verification needed |
|---|---|---|
| All three dimensions match | A dimensional candidate is present | Confirm seating angles and the full component specification |
| Only one angle is published | The reference is incomplete for a two-angle comparison | Do not invent the second angle |
| An alternate number is listed by a supplier | A claimed reference relationship exists | Check both makers' exact records before declaring interchange |
A practical investigation sequence
Identify and record
Start with the complete bearing marking and component position. Use the identification guide if the number on the frame describes the headset instead of the cartridge.
Check the context
Enter dimensions in millimetres and choose the angle marking only when known. Leave an unknown field blank; it is not zero.
Verify before acting
Compare every returned row, including source limitations. A single diameter or the family name does not establish compatibility.
Keep the decision traceable
Retain the exact manufacturer reference and verify the headset maker's application requirements before ordering or installing any component.
Capture the information a model search cannot guess
Keep this checklist with your inspection or comparison. Checking a box only records that you have collected the item; it does not certify the bearing.
0 of 4 information groups recorded.
Technical basis & editorial scope
Original BearingScope workflow, written for catalogue research and comparison. Manufacturer material is used to check principles, not copied as a product endorsement or substituted for model-specific instructions. Reviewed 1 October 2026.
- Enduro headset-bearing model pages — reviewed catalogue snapshot — 39 reviewed geometry records. Individual source pages and conflicted/withheld records are retained in the private audit. No load ratings or automatic fitment claims.
- Cane Creek replacement bearing specifications — Series and cross-brand compatibility limitations; no retailer reviews used.
- Acros — headset specifications and bicycle-model finder — Source-listed kits, upper/lower assemblies and exact recorded model/year conditions, checked 4 October 2026. Conflicting associations withheld; no inferred interchange or service instructions.
Source addresses and collection status are retained in the internal audit. No unpublished dimensions, torque settings, service intervals or interchange approvals are inferred.