RockShox BoXXer Fork
What the checker says2278will not fit88check before you buy1644worth knowing
Run variant by variant through the mountain bike builder’s own engine. Every sentence below is the checker’s, unedited. Nothing here says this part fits your bike; it says what it does and does not fit among the parts we hold.
Checked against 5708 verified mountain bike parts in this catalog. 4680 produced no finding of any kind; that is BoXXer Base D1 200 (29) (2023). BoXXer Ultimate 200 (27.5) (2023) clears 4157. Each variant produces 268 to 497 distinct errors and 13 to 14 distinct warnings.
Will not fit
- Will not fiterror · Front TireFront wheel size mismatch: Fork 27.5", Front tire 29". On 371 of the 618 verified tires in this catalog. Applies to 10 of 20 variants.
- Will not fiterror · Rear TireUnsupported wheel setup: front 27.5" / rear 29" matches no configuration (24"/24", 26"/26", 27.5"/27.5", 29"/29", 32"/32", mullet = 29" front / 27.5" rear). On 371 of the 618 verified tires in this catalog. Applies to 10 of 20 variants.
- Will not fiterror · Rear WheelUnsupported wheel setup: front 27.5" / rear 29" matches no configuration (24"/24", 26"/26", 27.5"/27.5", 29"/29", 32"/32", mullet = 29" front / 27.5" rear). On 364 of the 613 verified rear wheels in this catalog. Applies to 10 of 20 variants.
- Will not fiterror · FrameSteerer mismatch: Fork is Straight 1.125 (dual-crown) but Frame headset is Tapered (1.5-1.125). On 233 of the 258 verified frames in this catalog. Applies to all 20 variants.
- Will not fiterror · Front WheelFront axle mismatch: Fork is 20x110 Boost (DH) but Front wheel hub is Boost 15x110. On 225 of the 276 verified front wheels in this catalog. Applies to all 20 variants.
- Will not fiterror · Front TireFront wheel size mismatch: Fork 29", Front tire 27.5". On 223 of the 618 verified tires in this catalog. Applies to 10 of 20 variants.
- Will not fiterror · Front WheelFront wheel size mismatch: Fork 27.5", Front wheel 29". On 181 of the 276 verified front wheels in this catalog. Applies to 10 of 20 variants.
- Will not fiterror · Front WheelFront wheel size mismatch: Fork 29", Front wheel 27.5". On 90 of the 276 verified front wheels in this catalog. Applies to 10 of 20 variants.
Headset steerer, Headset. 1320 more findings from the same check, on up to 1 of the 70 verified headsets each.
Fork travel, Frame. 477 more findings from the same check, on up to 2 of the 258 verified frames each.
Wheel config, Frame. 239 more findings from the same check, on up to 2 of the 258 verified frames each.
Front brake mount, Front Brake. 120 more findings from the same check, on up to 1 of the 93 verified brakes each.
Front rotor min, Front Rotor. 60 more findings from the same check, on up to 47 of the 177 verified rotors each.
Fork travel min, Frame. 19 more findings from the same check, on up to 1 of the 258 verified frames each.
Front axle, Front Wheel. 4 more findings from the same check, on up to 10 of the 276 verified front wheels each.
Front wheel size, Front Rim. 4 more findings from the same check, on up to 3 of the 75 verified rims each.
Front wheel size, Front Tire. 4 more findings from the same check, on up to 21 of the 618 verified tires each.
Front wheel size, Front Wheel. 4 more findings from the same check, on up to 3 of the 276 verified front wheels each.
Wheel config, Rear Rim. 4 more findings from the same check, on up to 3 of the 75 verified rims each.
Wheel config, Rear Tire. 4 more findings from the same check, on up to 21 of the 618 verified tires each.
Wheel config, Rear Wheel. 4 more findings from the same check, on up to 7 of the 613 verified rear wheels each.
Front axle, Front Hub. 3 more findings from the same check, on up to 2 of the 40 verified front hubs each.
Open a variant in the builder to see the ones that apply to your own parts.
Check before you buy
- Check before you buywarning · FrameFork travel: 200mm exceeds the frame's rated max of 150mm. On 12 of the 258 verified frames in this catalog. Applies to 8 of 20 variants.
- Check before you buywarning · FrameFork travel: 180mm exceeds the frame's rated max of 150mm. On 12 of the 258 verified frames in this catalog. Applies to 6 of 20 variants.
- Check before you buywarning · FrameFork travel: 190mm exceeds the frame's rated max of 150mm. On 12 of the 258 verified frames in this catalog. Applies to 6 of 20 variants.
- Check before you buywarning · FrameFork travel: 200mm exceeds the frame's rated max of 170mm. On 11 of the 258 verified frames in this catalog. Applies to 8 of 20 variants.
- Check before you buywarning · FrameFork travel: 180mm exceeds the frame's rated max of 170mm. On 11 of the 258 verified frames in this catalog. Applies to 6 of 20 variants.
- Check before you buywarning · FrameFork travel: 190mm exceeds the frame's rated max of 170mm. On 11 of the 258 verified frames in this catalog. Applies to 6 of 20 variants.
Front tire fork, Front Tire. 60 more findings from the same check, on up to 1 of the 618 verified tires each.
Fork travel, Frame. 20 more findings from the same check, on up to 10 of the 258 verified frames each.
Front rotor max, Front Rotor. 1 more finding from the same check, on up to 5 of the 177 verified rotors each.
Steerer, Frame. 1 more finding from the same check, on up to 8 of the 258 verified frames each.
Open a variant in the builder to see the ones that apply to your own parts.
Worth knowing
- Worth knowinginfo · FrameHeadset: Antidote Carbonjack takes ZS44 upper / ZS56 lower cups (S.H.I.S.) to mount the fork - many frames ship with one; pick one here if yours does not. On 2 of the 258 verified frames in this catalog. Applies to all 20 variants.
Headset advisory, Frame. 1643 more findings from the same check, on up to 1 of the 258 verified frames each.
Open a variant in the builder to see the ones that apply to your own parts.
$1,299.00 to $2,099.00 MSRP·2840 to 2950 g
What the maker states
- Travel
- 200 mm of travel (maker-stated) (on 8 of 20 variants); 180 mm of travel (maker-stated) (on 6 of 20 variants); 190 mm of travel (maker-stated) (on 6 of 20 variants)
- Wheel
- Built for a 27.5" wheel (on 10 of 20 variants); Built for a 29" wheel (on 10 of 20 variants)
- Axle
- Front axle 20x110 Boost (DH)
- Steerer
- Straight 1.125 (dual-crown)
- Minimum front rotor
- Front rotor no smaller than 200 mm
- Maximum front rotor
- Front rotor up to 220 mm (maker-stated maximum)
A value shown as a set or a range differs between this model’s variants and is never one variant’s spec.
20 verified variants
| Variant group | Ultimate | Ultimate D2 | Select D2 | Base D1 |
|---|---|---|---|---|
| Variants | BoXXer Ultimate 200 (29) (2023) BoXXer Ultimate 200 (27.5) (2023) | BoXXer Ultimate D2 180 (29) (2027) BoXXer Ultimate D2 190 (29) (2027) BoXXer Ultimate D2 200 (29) (2027) BoXXer Ultimate D2 180 (27.5) (2027) BoXXer Ultimate D2 190 (27.5) (2027) BoXXer Ultimate D2 200 (27.5) (2027) | BoXXer Select D2 180 (29) (2027) BoXXer Select D2 190 (29) (2027) BoXXer Select D2 200 (29) (2027) BoXXer Select D2 180 (27.5) (2027) BoXXer Select D2 190 (27.5) (2027) BoXXer Select D2 200 (27.5) (2027) | BoXXer Base D1 180 (29) (2023) BoXXer Base D1 190 (29) (2023) BoXXer Base D1 200 (29) (2023) BoXXer Base D1 180 (27.5) (2023) BoXXer Base D1 190 (27.5) (2023) BoXXer Base D1 200 (27.5) (2023) |
| Travel | 200 mm of travel (maker-stated) | 180 mm of travel (maker-stated) (on 2 of 6 variants); 190 mm of travel (maker-stated) (on 2 of 6 variants); 200 mm of travel (maker-stated) (on 2 of 6 variants) | 180 mm of travel (maker-stated) (on 2 of 6 variants); 190 mm of travel (maker-stated) (on 2 of 6 variants); 200 mm of travel (maker-stated) (on 2 of 6 variants) | 180 mm of travel (maker-stated) (on 2 of 6 variants); 190 mm of travel (maker-stated) (on 2 of 6 variants); 200 mm of travel (maker-stated) (on 2 of 6 variants) |
| Wheel | Built for a 27.5" wheel (on 1 of 2 variants); Built for a 29" wheel (on 1 of 2 variants) | Built for a 27.5" wheel (on 3 of 6 variants); Built for a 29" wheel (on 3 of 6 variants) | Built for a 27.5" wheel (on 3 of 6 variants); Built for a 29" wheel (on 3 of 6 variants) | Built for a 27.5" wheel (on 3 of 6 variants); Built for a 29" wheel (on 3 of 6 variants) |
| Axle | Front axle 20x110 Boost (DH) | Front axle 20x110 Boost (DH) | Front axle 20x110 Boost (DH) | Front axle 20x110 Boost (DH) |
| Steerer | Straight 1.125 (dual-crown) | Straight 1.125 (dual-crown) | Straight 1.125 (dual-crown) | Straight 1.125 (dual-crown) |
| Minimum front rotor | Front rotor no smaller than 200 mm | Front rotor no smaller than 200 mm | Front rotor no smaller than 200 mm | Front rotor no smaller than 200 mm |
| Maximum front rotor | Front rotor up to 220 mm (maker-stated maximum) | Front rotor up to 220 mm (maker-stated maximum) | Front rotor up to 220 mm (maker-stated maximum) | Front rotor up to 220 mm (maker-stated maximum) |
| Brake mount | Post mount | Post mount | Post mount | Post mount |
| Maximum tire mm | Tire up to 81 mm (maker-stated maximum) | Tire up to 81 mm (maker-stated maximum) | Tire up to 81 mm (maker-stated maximum) | Tire up to 81 mm (maker-stated maximum) |
| Price (MSRP) | $2,099.00 | $1,999.00 | $1,499.00 | $1,299.00 |
| Weight | 2880 g | 2850 g | 2950 g | 2840 g |
| Model year | 2023 | 2027 | 2027 | 2023 |
| Price basis | price: MSRP confirmed against the manufacturer | price: MSRP confirmed against the manufacturer | price: MSRP confirmed against the manufacturer | price basis varies by variant. Open one to see it |
| Source | maker’s page | maker’s page | maker’s page | maker’s page, maker’s page |
| Last checked | 2026-08-04 | 2026-07-18 | 2026-07-11 | 2026-07-17 to 2026-09-02 |
| Build with this | Build with BoXXer Ultimate 200 (29) (2023) | Build with BoXXer Ultimate D2 180 (29) (2027) | Build with BoXXer Select D2 180 (29) (2027) | Build with BoXXer Base D1 180 (29) (2023) |
The rest of what the maker states3 stated·1 not published
- Brake mount Post mount.
- Tire up to 81 mm (maker-stated maximum).
- Maximum tire basis: measured.
1 further field the checker looks for is not published by RockShox, so we leave it blank rather than estimate it, and that check stays silent on this fork. It is maximum tire. Each is recorded as “not stated by the maker (not checked)”.
Source: each variant links the maker’s own page in the table above. Last checked 2026-07-11 to 2026-09-02.
Checked against
The checker ran this model against every verified part below that it has a slot for, the same way it checks a build in the builder. What follows is the verdict it actually produced for that specific pairing — not a recommendation, and not a guarantee any of these parts fits your own bike.
- 5DEV R-SPEC Trail/Enduro Cranks (Crankset) No conflicts found
- 9point8 Fall Line (Dropper Post) No conflicts found
- 9point8 Stout (31.8, 30mm) (Stem) No conflicts found
- ACID Pro 25 front (Front Wheel) Will not fit
- ACID Pro 25 rear (Rear Wheel) Will not fit
- ACID SLX 30 front (Front Wheel) Will not fit
6 of 1864 counterparts with a page of their own that the checker actually probed this model against, in alphabetical order by brand and model — never by price, popularity or the verdict itself.