Curve Cycling - Fork, Handlebar & Accessory Introduction for Framebuilders

Making this post to introduce the various forks, handlebars and other small accessories available from Curve Cycling, as I think it’s probably not very well known that we offer special pricing to support independent framebuilders and small to medium brands who may rely on third parties for forks etc.

Full disclosure: My full-time job is as a product developer at Curve, where I do all the design and CAD work (amongst other things). I’ve been hesitating to make a post like this, as I’m very conscious of the risk it would be seen as self-promotion or advertising. Hence, I recently reached out to @Daniel_Y and got the go-ahead to post this.

In my obviously biased opinion, we have some really good forks and handlebars in our lineup, some with geo specs and features that set them apart from the usual suspects.

I won’t post pricing here since it can change unexpectedly. I know many of you here are located in the US, so tariffs and import costs can be an issue. Hopefully that changes soon!
Just get in touch via PM here, or ideally via the Curve contact form, if you have any questions or want to explore placing an order.

I have not included any photos in this post at this stage, as it’s already taken me far too long to type up, but I will add some later. I’ve put in links to each product page where you can see all the details incl. photos.

Forks:

We’ve used our longstanding “Race | Ride | Seek” slogan to categorise the forks, and the (approximate) length of each model is also indicated in the name.

Race = No cargo mounts | Ride = Mainly gravel | Seek = Offroad & bikepacking

Race 370
The simplest fork in our lineup. It’s a traditional road disc fork.

SPECS NOTES
Length: 370.7mm [Axle to crown]
Offset: 45mm
Steerer: Tapered 1 1/18" - 1.5", 300mm long Max 30mm spacer limit
Brake: Flat Mount, 140/160mm native
Cables: Semi-internal
Hub Spec: 12 × 100mm thru-axle
Axle Spec: M12 × 1.5p, 125mm length
Tyre Clearance: 700c × 33mm
Mounting Points: None
Weight: ~415g
Kit Includes: Steerer Expander w. topcap, Axle
Other: 120kg system weight rating

Race 380 - Currently in production - Release TBC
Our latest fork that’s due to be available to order in the coming months. Designed as a “Road+” fork for our new generation road/allroad endurance model. One staff member is using it on his CX bike. Option to run fully internal or semi-internal brake routing. The cable port on the shoulder of the fork leg has a cover when not used as a cable exit.

SPECS NOTES
Length: 380mm
Offset: 47mm
Steerer: Tapered 1 1/18" - 1.5", 370mm long 45° integrated crown race Max 30mm spacer limit
Brake: Flat Mount, 160/180mm native
Cables: Semi-internal, full internal
Hub Spec: 12 × 100mm thru-axle
Axle Spec: M12 × 1.5p, 117mm length 90° conical head
Tyre Clearance: 700c × 40mm w. fender, will clear >42mm without a fender.
Mounting Points: Fender mounts on leg and under crown Under-crown mount can be used for a light as well (light mount in the works)
Weight: ~415g
Kit Includes: Steerer Expander w. topcap, Axle, cable port plugs
Other: 120kg system weight rating 3D printed Ti entry port for the brake hose. Internal dynamo routing compatible

Ride 415 VGM
The second-generation Ride 415 fork that we use for our gravel and 'Gravel-Plus" models. We re-tooled with a new mold to incorporate the “VGM” cargo mount system. And while we were at it, we also changed the Flat Mount spec to allow larger rotors. VGM stands for “Very Good Mounts” and was developed so we could finally get rid of those pesky rivnuts that always seem to cause problems. These mounts consist of two pieces that pierce both sides of the fork legs for extra support. The mounts are bonded to the fork, and the heads have a larger surface area than a rivnut. All our cargo-capable forks will use this system from now on.
Tuneable offset via flip-chips. All cable routing is external.

SPECS NOTES
Length: 415mm [On-Axis]
Offset: 46mm / 52mm
Steerer: Tapered 1 1/18" - 1.5", 350mm long Max 30mm spacer limit
Brake: Flat Mount, 160/180mm native
Cables: External. Brake & dynamo cable clips included
Hub Spec: 12 × 100mm thru-axle Can accept a 15mm axle hub with reduction sleeve
Axle Spec: M12 × 1.5p, 125mm length
Tyre Clearance: 29" × 2.4"
Mounting Points: 3 x VGM mounts / leg, thru-crown ‘tunnel’ (not threaded) for M5 bolt to accept a rack or light
Weight: ~554g
Cargo Capacity: 8kg/leg (across 3 mounts)
Kit Includes: Steerer Expander w. topcap, Axle, Flip-Chips, Cable Clips
Other: 120kg system weight rating The inside of the VGM mounts have an M4 thread - can be used for fender struts Also available in a ‘Race’ version with no cargo mounts, semi-internal routing and 140/160mm Flat Mount
Tech Links: BOM Dimensions Flip-Chip Manual

Seek 430 PM
The first generation of the fork we developed for our GMX+ platform. Non-suspension corrected off-road touring fork for up to 29" x 3.0" tyres.

Currently on run-out pricing, and limited numbers are available - we may not produce the PM version of this fork again.

SPECS NOTES
Length: 430mm [On-Axis]
Offset: 55mm
Steerer: Tapered 1 1/18" - 1.5", 300mm long Max 30mm spacer limit
Brake: Post Mount, 180mm native May not fit especially bulky calipers. Contact me for details, or check the product FAQ.
Cables: External. Brake & dynamo cable clips included
Hub Spec: 15 × 110mm thru-axle
Axle Spec: M15 × 1.5p, 143mm length
Tyre Clearance: 29" × 3.0"
Mounting Points: 6 x mounts / leg
Weight: ~619g
Cargo Capacity: 3kg/leg (across 3 mounts)
Kit Includes: Steerer Expander w. topcap, Axle, Cable Clips
Other: 140kg system weight rating (120kg rider + bike & cargo)
Tech Links: Dimensions

Seek 430 FM
The second generation of the fork we developed for our GMX+ platform. Non-suspension corrected off-road touring fork for up to 29" x 3.0" tyres. Same dimensions and overall design as the Post Mount version above, but using a new mold to incorporate the VGM system, a longer steerer, and with Flat Mount instead of Post Mount.

SPECS NOTES
Length: 430mm [On-Axis]
Offset: 55mm
Steerer: Tapered 1 1/18" - 1.5", 350mm long Max 30mm spacer limit
Brake: Flat Mount, 160/180mm native
Cables: External. Brake & dynamo cable clips included
Hub Spec: 15 × 110mm thru-axle
Axle Spec: M15 × 1.5p, 143mm length
Tyre Clearance: 29" × 3.0"
Mounting Points: 4 x VGM mounts / leg
Weight: ~646g
Cargo Capacity: 8kg/leg (across 3 mounts)
Kit Includes: Steerer Expander w. topcap, Axle, Cable Clips
Other: 140kg system weight rating (120kg rider + bike & cargo)
Tech Links: Dimensions

Seek 500
Rigid MTB / Bikepacking fork that’s suspension-corrected to replace a 120-130mm travel fork. Tuneable offset via flip-chips as well as Boost / Non-Boost compatible thanks to a movable Post Mount bracket and “Deboosterator Pads”. Features our VGM mounts and a crown thru-hole for rack mounting, which is unusual on this type of fork. All cable routing is external.

SPECS NOTES
Length: 497mm [On-Axis]
Offset: 44mm / 52mm
Steerer: Tapered 1 1/18" - 1.5", 350mm long Max 30mm spacer limit
Brake: Post Mount, 180mm native Removable PM Mount has two lateral positions
Cables: External. Brake & dynamo cable clips included
Hub Spec: 15 × 110mm 15 × 100 thru-axle when using the optional “Deboosterator pads”
Axle Spec: M15 × 1.5p, 143mm length
Tyre Clearance: 29" × 3.0"
Mounting Points: 4 x VGM mounts / leg, thru-crown ‘tunnel’ (not threaded) for M5 bolt to accept a rack or light
Weight: ~740g
Cargo Capacity: 8kg/leg (across 3 mounts)
Kit Includes: Steerer Expander w. topcap, Axle, Flip-Chips, Cable Clips
Other: 120kg system weight rating (rider, bike & cargo)
Tech Links: BOM Dimensions Flip-Chip Manual & Flip-Chip Animation

Handlebars:

Walmer Bar
Alloy gravel/bikepacking handlebar. The wider sizes (50cm & up) are specifically intended for our GMX+ off-road touring model (or similar). Ridiculous width for a drop bar, which works surprisingly well on the right bike.
The narrower sizes also work well for road/allroad if you don’t mind the flare.

SPECS NOTES
Width at Hoods: 40cm / 43cm / 46cm / 50cm / 55cm / 60cm
Reach: 65mm 60mm (sizes 55 & 60)
Drop: 110mm
Flare: 29°
Sweep:
Aerobar Compatible: Yes
Wired Di2 Compatible: Yes
Clamping Area: 120-220mm depending on overall width
Weight: ~358g / 378g / 397g / 422g / 423g / 450g
Other: Includes bar tape (made by Velo)

Carbon Walmer Bar
Carbon version of the Walmer handlebar. A little lighter. Slightly ‘aero’ tops for more comfort and compliance. Has an embedded Kevlar layer in clamping areas to reduce the risk of crush damage and catastrophic failure. Tested to the equivalent of XC MTB riding for a 120kg rider.
Also features a cable channel that eliminates the bump from the brake hoses when wrapping the bars.
The latest batch has been updated with internal routing compatibility.

SPECS NOTES
Width at Hoods: 43cm / 46cm / 50cm
Reach: 65mm 62.5mm (size 50)
Drop: 108mm
Flare: 30°
Sweep:
Cable routing: External or Internal
Aerobar Compatible: Yes
Wired Di2 Compatible: Yes
Clamping Area: 150mm (43cm), 180mm (46 & 50cm)
Weight: ~304g / 316g / 334g
Other: Includes bar tape (made by Velo)

Race Walmer Bar - Currently in production - Release TBC
Even lighter and even more aero version of the Walmer bar. Same overall drop shape, but with half the flare. The drops have recesses for blips. The recess can be filled with the included 3D printed insert before wrapping the bars for a more traditional grip feel.
The cable channel underneath the aero tops directs the cable back towards the steerer & under the stem for a nice and clean cable arrangement when running external cables.
Tested to the equivalent of gravel racing for a 120kg rider.

We may at some point expand the size options to include a 38cm (maybe even 36cm) and a 42cm variant, depending on demand.

SPECS NOTES
Width at Hoods: 40cm
Reach: 65mm
Drop: 108mm
Flare: 14°
Sweep:
Cable routing: External or Internal
Aerobar Compatible: Yes
Wired Di2 Compatible: Yes
Clamping Area: 100mm
Weight: ~220g
Other: Includes bar tape (made by Velo) & Blip recess inserts

Other Parts

  • Relaxle - 12 & 15mm Thru-axles developed for our own frames and forks, so sizes are limited. Features a 6mm allen key broach on either end with an M5 thread at the bottom for rack/fender mounting.
  • Crown Race Mounts - Fits underneath the crown race on a 1.5" tapered steerer. GoPro or M6 fitment to attach a light, or a rack on forks with no crown thru-hole
  • 3D printed front derailleur clamp - Stiff and minimal clamp. Available in Ø31.8 and Ø34.9mm sizes. Other sizes can be organised. A single M4 bolt to secure the clamp to the seattube. The bolt is tucked away nicely behind the derailleur, leaving a clean look.
  • Flat Mount Adapter [+40mm] - Front Flat mount adapter to allow a fork with a 140/160mm FM interface to accept a 180mm rotor.
  • 104BCD Spider for SRAM 8-bolt cranks - Designed and made this to be able to fit a Gates Sprocket on the latest SRAM MTB (T-Type) cranks. (~3mm offset with chainring mounted).
8 Likes

Jimmy , this is awesome I’m sure it will be much appreciated as it offers an alternative to whats out there !

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I like these forks a lot. We used a Seek 500 on this build….

2 Likes

Nice looking fork. Wish it was easier to get one in the USA

That looks great.
Glad you like it!

Sorry man… we’ve had to focus a lot on other markets due to all the recent shenanigans from the current US administration.

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i keep hoping a seek 450 or 455 with 55mm+ offset might appear to clear those new fangled 32” wheels ;-)~

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Can’t make any promises yet. But I’d say that if our experimentation with 32" wheels work out the way we expect, we’ll likely make a fork to match. Maybe a bit more offset that 55mm though. But we have some prototype testing to do first. :slight_smile:

1 Like

Seek 500 is a really nice looking fork.

I have a question on suspension correction that I’ve wondered about for a while – and it’s not targeted at you because I see this industry wide. Why is a 500mm A-C fork considered suspension corrected for a 120-130mm fork instead of 100-110mm? A Fox 34 set to 120mm travel is 531mm and Fox suggests 15-20% sag. Other 120mm forks are within a few mm of that.

120mm Fox 34 @ 20% sag: 120x0.2=24, 531-24=507mm.
130mm Fox 34 @ 20% sag: 130x0.2=26, 541-26=515mm.

110mm fork at 20% sag: 110x0.2=22, 521=22=499mm – right on target for a 500mm fork.

I’m asking because I’m designing a XC/bikepacking-ish bike where we want to support rigid and suspension forks. I sampled a lot of rigid forks, and 490mm is about the median length (some being as short at 483, some as long as 505) – so I designed the bike for a 490mm rigid or 100mm (510ish A-C without sag) suspension fork.

I’ve wondered if 490-500mm A-C is the sweet spot for rigid forks, with anything longer requiring the blades to get too beefy for decent aesthetics.

The Seek 500 looks like it would be perfect for someone who wanted rigid but to slacken out the bike slightly from our design point. I totally understand ignoring the US market with the current administration, hopefully that gets resolved in the future.

I think this is a combination of historical practices and also an assumption of at what length the fork actually rides. Chances are that you load up the fork a bit more during active riding than when setting the sag since that’s a static reading. This will, of course, also depend on your riding style.

Some brands also suggest a larger range of sag than FOX - RockShox, for example, suggest a 15-25% range.

Back when we had a 480mm long rigid fork (before my design days at Curve), that one was said to be adjusted for a 100mm travel fork. So from our perspective, when we set out to design a fork corrected for 120mm travel, it was natural to go to 500mm in length.

I used some data readily available from RockShox and found that there is some variance across models with the same amount of travel.

For example, I found that their 29" 100mm travel forks vary in length from 505mm (Recon Silver) to 519 (Recon Silver RL Boost) and a 29" 120mm from 527mm (Judy) to (Recon Gold in 51mm offset).

Put together a little spreadsheet with my findings and some sag calculations.
I’ve highlighted values within +/-5mm of the target 500mm length.

I think that for the purpose of calculating suspension-correction, it makes sense to use the higher sag value as I believe most suspension forks probably ride a bit lower than sag, on average, during active riding.

2 Likes

Thanks for the detailed reply and the spreadsheet. Like I said I’m not trying to pick on Curve here, I see these numbers from other suppliers as well.

I wonder what forks caused people to pick 480mm for 100mm travel? Maybe it was based off of 27.5 forks that were 20mm shorter?

Rock Shox also seems to recommend 15-20% sag for the XC (100-120mm) forks from what I can see. Overall my read of your spreadsheet would put 500mm solidly in the 110mm suspension corrected range, but most riders probably aren’t that sensitive to half degree angle changes. Since you list the actual A-C people can figure out what works for them. I noticed that Ritchey, Salsa, and others have stopped claiming what travel suspension fork their rigid fork will replace. I am curious to see if 510-520mm (vs 483-500mm today) becomes more common as bikes designed around 100-120mm forks become more rare.

The 505mm for the Rock Shox Silver caught my eye since that’s pretty short, but looking at the specs it is for the straight steerer/QR version of the fork. That’s not too likely to be run on a modern custom bike, and the tapered version has 513mm A-C.

For anyone else following along Rock Shox A-C lengths are here:

Fox doesn’t share one big table, but you can find it on the drawing per fork. Like this is for the Fox 34:

and 34SL (goes down to 110mm) is here:

What hub size are you planning to use?

Imo 110 mm looks a little bit awkward on a big wheel. 135 mm would definitely be an interesting option, and the wheel’s lateral stiffness would benefit a lot. There are plenty of hubs available in this standard too but not much fork options. Also it could fit fatbike tires.

We have not started evaluating that yet.
Fully aware of the benefits of a larger bracing angle. That said, when we were playing around with a 36er prototype, we stuck with standard boost spacing front and rear to test the limits. That bike has been ridden quite hard by multiple people and riding styles, and the wheels are still intact.

Extra hub width may be a case of “looks good on paper, but has little real-world effect”. Or we may just have been lucky so far.

1 Like