CeramicSpeed Headset Compatibility
Headset SHIS
Single Headset Bearings
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| Fork Steerer |  | SHIS If upper | SHIS If lower | Common drop in fitment | ||
| HS bearing 1" | 27,15x38x6,5mm, 36/45 degrees | IS38/25.4 | IS38/26 | Specialized | ||
| HS bearing 1-1/8" | 30,5x41,8x8mm, 45/45 degrees | IS42/28.6 | IS42/30 | Specialized, Pinarello | ||
| HS bearing 1-1/4" | 34,1x46,9x7mm, 45/45 degrees | IS47/31.8 | IS47/33 | Specialized | ||
| HS bearing 1-3/8" | 37x49x7mm, 45/45 degrees | Â - | IS49/37(45) | Specialized | ||
| HS bearing 1-1/2" | 40x52x7mm, 45/45 degrees | IS52/38.1 | IS52/40(45) | Specialized, Pinarello | ||
| HS bearing 1-1/8" | 30,15x41x7mm, 45/45 degrees | IS41/28.6 | IS41/30(45) | Cervelo Upper | ||
| HS bearing 1-1/8" | 30,15x41x7mm, 36/45 degrees | IS41/28.6 | IS41/30(36) | Cervelo Lower | ||
| HS bearing 1-3/8" | 37x48,9x6,5mm, 36/45 degrees | Â - | IS49/37(36) | Cervelo / Factor | ||
| HS bearing 1-1/2" | 40x51,8x8mm, 36/45 degrees | IS52/38.1 | IS52/40(36) | Cervelo | ||
| HS bearing 1-1/4" | 34,1x46x7mm, 45/45 degrees | IS46/31.8 | IS46/33 | Scott | ||
| HS bearing 1-1/2" | 40x51,9x8mm, 45/45 degrees | IS52/38.1 | IS52/40(45) | Scott | ||
| HS bearing 1-1/8" | 30,15x41x6,5, 36/45 degrees | IS41/28.6 | IS41/30(36) | Scott / Factor | ||
| HS bearing 1-1/8" | 30,2x41,8x6,3mm 45/45 degrees | IS42/28.6 | IS42/30 | Cannondale | ||
| HS bearing 1-1/2" | 40x51x6,5mm 36/36 degrees | IS51/38.1 | IS51/40(36) | Trek | ||
Complete Headset Kits
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| Name / Designation | Compatible with | Fork Steerer | SHIS (upper, space, lower) | Bearings included |
| Specialized HS 1 | Shiv TT (UCI Legal, used on WT teams) | Upper: 1" Lower: 1-1/8"Â | IS38/25.4 IS42/30 | 101523 + 101533 |
| Specialized HS 2 | Tarmac SL5 size 49-52 | Upper: 1-1/8" Lower: 1-1/4" | IS42/28.6 IS47/33 | 101533 + 101529 |
| Specialized HS 3 | Tarmac SL5 size 54-56 & Venge | Upper: 1-1/8" Lower: 1-3/8" | IS42/28.6 IS49/37(45) | 101533 + 101540 |
| Specialized HS 4 | Tarmac SL5 size 58+ & SL6 all sizes | Upper: 1-1/8" Lower: 1-1/2" | IS42/28.6 IS52/40 | 101533 + 101525 |
| Specialized HS 5 | Shiv Tri (not UCI legal, used in triathlon) | Upper: 1-1/8" Lower: 1-1/8" | IS42/28.6 IS42/30 | 2x 101533 |
| Cervelo HS 1 | 2017 & older R-series + 2018 & older S-series | Upper: 1-1/8" Lower: 1-3/8" | IS41/28.6 IS49/37(36) | 101536 + 101542 |
| Cervelo HS 2 | 2018 & older P-series | Upper: 1-1/8" Lower: 1-1/8" | IS41/28.6 IS41/30(36) | 101536 + 101538 |
| Cervelo HS 3 | 2018 & newer R-series, C-series, P5X, & P3XÂ | Upper: 1-1/8" Lower 1-1/2" | IS41/28.6 IS52/40 | 101536 + 103285 |
| Cervelo HS 4: please order individual bearings from links to the right | P5 Disc & S5 Disc | Upper: 1" Lower: 1-3/8" | IS38/25.4 IS49/37(36) | 101523 + 101542 |
| Cervelo HS 5: please order individual bearings from links to the right | 2019 & newer S3 Disc & S3 Rim | Upper: 1-1/4" Lower: 1-3/8" | IS47/31.8 IS49/37(36) | 101529 + 101542 |
| Scott HS 1 | Addict/Solace | Upper: 1-1/8" Lower: 1-1/4" | IS41/28.6 IS46/33 | 101536 + 101531 |
| Scott HS 2 | Foil | Upper: 1-1/4" Lower: 1-1/2" | IS46/31.8 IS52/40 | 101531 + 101527 |
| Scott HS 3 | Plasma | Upper: 1-1/8" Lower: 1-1/8" | IS41/28.6 IS41/30(36) | 2x 103284 |
| Pinarello HS 1 | F8/F10 no split ring included | Upper: 1-1/8" Lower: 1-1/2" | IS41/28.6 IS52/40 | 101533 + 101525 |
| Outboard HS | 44mm straight headtube | Upper: 1-1/8" Lower: 1-1/4" | ZS44/28.6 EC44/33 | 101536 + 101531 |
| Outboard HS | 34mm traditional straight headtube | Upper: 1-1/8" Lower: 1-1/8" | EC34/28.6 EC34/30 | 2x 101536 |
| Outboard HS | 44mm straight headtube | Upper: 1-1/8" Lower: 1-1/2" | ZS44/28.6 EC44/40 | 101536 + 101525 |
| Outboard HS | 34mm/44mm tapered headtube | Upper: 1-1/8" Lower: 1-1/4" | EC34/28.6 EC44/33 | 101536 + 101531 |
