GRC-3 | MantaRay | Seven Cycles

U.S. Built Custom Bicycles in Titanium and Titanium-Carbon Mix

Navigate: All MantaRays Parts Kit Frame Geometry Tubeset Options Frameset Specifications Order

The GRC-3 may be the perfect balance of price, innovation, lightweight, and precision. Seven's hand-made titanium frame with the most progressive design ever built paired with SRAM's Rival AXS 1x is hard to beat.

Once you've decided on your model and upgrades, reserve your MantaRay:

Reserve my MantaRay now

MantaRay tire clearance — MantaRay clearances thanks to our Dual-Diameter chainstays. 30% stiffer than standard. And fits a 700c x 43 mm knobby tire with more clearance than any stock bike we've measured. Room for a 42t front chainring. And perfect chainstay length for serious gravel riding.

MantaRay BB alignment of 0.001∈ — MantaRay welding alignment check. This bottom bracket shell is within 0.001″ square to the frame's plane at and will stay there forever. That's about 1/3 the thickness of a piece of paper. Weld straight = ride straight.

Group Set Details

Kitted out with SRAM's Rival AXS gravel-centric mullet group set. Affordable electronic shifting, upgradeable, and designed for the toughest gravel conditions. Skip the front derailleur. 1x chainring is simpler, lighter, and has less-to-no chain drop.

Complete bike weight: This build-out has an average calculated weight of 8.55 kilos, 18.8 lbs.^[10] Lighter setups and upgrades are available.

Component	SRAM Rival/GX AXS 1x12-speed mullet
Shift & brake levers	Rival AXS, electronic
Derailleurs	Rear: SRAM GX // Front: Not applicable; Seven MantaRays have 1x front chainrings.
Brakes	Rival hydraulic // Rotors: SRAM, centerlock, 160 mm front & rear; + caliper adapter for rear 160 mm rotor
Crankset & bottom bracket	Rival, length is size specific // Chainring: 40t 1x12-speed // Bottom bracket: Wheels Manufacturing T47 oversized threaded, 68 mm width, black
Cassette & chain	Rival: 12-speed 10-52t // Chain: Rival Flattop, 12-speed with quick link
Gear ratios	Minimum 0.77 to 4.00 maximum

Build-Out Details

Part	Specification
Fork	Frame size and geometry dependant. Either Seven's exclusive proprietary Matador 750 carbon fork or Enve's gravel carbon fork. Thru-axle is 6 mm hex head. (Brake caliper includes fork mount adapter for 160 mm rotor.)
Wheelset, 700c	HED Emporia GA Performance, aluminum, centerlock, thru-axle: front 12 x 100 mm, rear 12 x 142 mm. Wheel set upgrades available on order page. // Thru-axle Robert Axle Project, 6 mm hex head. // Tires: 700c x 40 mm Continental Terra Speed, tubeless-ready, folding // Tire pressure management: Tubeless, rim strips, valve stems, sealant
Cockpit: Handlebar, stem, seat post	Handlebar: Zipp Service Course XPLR: aluminum, black, diameter, 31.8 mm; width is size specific // Bar tape: Fizik Vento Microtek tacky, thickness 2.0 mm, black // Stem: Zipp Service Course: aluminum, black, angle 97/83 degree, stack 41 mm, diameter 31,8 mm; length is size specific // Seat post: Zipp Service Course: aluminum, setback 20 mm, diameter: 27.2 mm
Saddle	PRO Stealth Performance, metal rails, black
Headset 44 mm	Cane Creek 40, black // Headset Spacers: Aluminum spacer pack: 3x 1.0 cm, black, 1-1/8"
Not included	Pedals Power meter Fenders for fork or frame Water bottle cages or bottles Any other accessories or additions that may be shown in associated bike photos

Footnotes:

Bike weights are estimated based on claimed component weights provided by manufacturers. We use average-sized components when there are options (crank length, etc.) and a 54.0 frame and fork cut for that size frame. We do not include pedals or any accessories in the estimated bike weight.

*The MantaRay head tube badge. Special Edition two layers of stainless steel, brazed by hand. Each is unique.*

Unbound 2022 pre-ride meeting — Racing Unbound 2022 was one of many proving grounds four our gravel frame design thinking. The MantaRay and FlowState innovation are two results of many races and events over the past four years. (Here is one of the pre-race talks.)

Navigate: All MantaRays Parts Kit Frame Geometry Tubeset Options Frameset Specifications Order

Standard Fit with Competition Performance Geometry

Frame size & top tube, effective^[1]	49.0 cm	51.0 cm	52.0 cm	53.0 cm	54.0 cm	55.0 cm	56.0 cm	57.0 cm	58.0 cm	59.0 cm	60.0 cm	62.0 cm
Frame stack, BB-HT^[2]	52.8	53.0	53.4	54.7	56.0	57.3	58.3	59.3	60.3	61.5	62.8	65.4
Frame reach, BB-HT^[3]	36.2	37.3	37.5	37.6	37.8	38.2	38.9	39.4	39.8	40.2	40.8	41.7
Head tube length	9.6	9.6	10.1	11.4	12.7	13.9	14.6	15.5	16.4	17.6	19.0	21.7
Head tube angle	68.50	69.50	69.75	70.25	70.75	71.50	71.75	72.25	72.50	72.75	72.75	73.00
Seat tube angle	76.75	75.75	75.00	74.50	74.00	73.75	73.75	73.50	73.25	73.00	73.00	72.75
Bottom bracket drop	8.2	8.0	7.8	7.7	7.6	7.5	7.5	7.4	7.4	7.3	7.3	7.2
Bottom bracket height	27.2	27.4	27.6	27.7	27.8	27.9	27.9	28.0	28.0	28.1	28.1	28.2
Chainstay length	44.8	44.8	44.8	44.8	44.8	44.8	44.8	44.8	44.8	44.8	44.8	44.8
Front center^[4]	60.7	60.7	60.7	60.7	60.7	60.7	60.9	61.2	61.4	61.9	62.9	64.4
Seat tube length^[5]	35.5	38.0	40.0	43.5	46.0	48.0	49.0	50.0	51.0	52.0	53.5	56.0
Top tube slope	18	15	13	10	9	8	8	8	8	8	8	8
Standover height^[6]	69.9	71.6	73.0	75.4	77.5	79.1	80.1	81.2	82.1	83.2	84.7	87.2
Rider height range (ft)^[7]	4' 10" to 5' 2"	5' 0" to 5' 4"	5' 1.5" to 5' 5.5"	5' 2.5" to 5' 7.5"	5' 5" to 5' 9"	5' 8" to 6' 0"	5' 10" to 6' 2"	6' 0" to 6' 4"	6' 2" to 6' 6"	6' 3" to 6' 7"	6' 4" to 6' 8"	6' 6" to 6' 10"
Rider weight range (lbs)^[8]^[9]	100 to 140	120 to 160	135 to 180	150 to 195	165 to 220	180 to 240	195 to 255	205 to 265	215 to 275	225 to 290	235 to 305	225 to 335

General Frame & Bike Geometry Notes

Measurements in centimeters and degrees. Bike geometry calculated with 700c x 40 mm knobby tires. Specifications subject to change.

Top tube length is effective: Starting from the centerline of the head tube and top tube intersection measured horizontally to the ground, back to the seat tube.
Frame stack BB-HT: This is what most bike companies simply call "stack." However, there is frame stack and separately bar/stem stack. Seven clarifies frame stack by including BB-HT. Because we only provide frameset specifications (rather than bike specifications), we cannot provide stem stack here.
Frame reach warning: This popular measurement is not a good gauge of proper bike fit. Also, the term is not accurate and, therefore, often causes confusion. Seven qualifies the term with "BB-HT" to help define the measurement. Regardless of these shortcomings, we include frame reach BB-HT because it has become a popular industry shorthand for comparing one bike size to another. While the frame reach numbers Seven shows here are accurate, Seven does not take responsibility for an ill-fitting bike if a fitter relies on the frame reach number. Top tube length combined with stem length is much more relevant and helpful in bike-to-bike fit comparisons.
Toe overlap warning: Because toe overlap is determined, in large part, by factors not related to frame geometry, we cannot guarantee that your bike setup will not have any overlap. Make sure you are comfortable with the length of the front center before ordering a bike. You can check your current bike to compare front centers.

Seat tube length is measured from the center of the bottom bracket to the intersection of the top tube's centerline. To determine the total seat tube length from the top edge of the seat top to the center of the bottom bracket, add about 4.5 cm.
Standover height is measured midway along the top tube, the actual typical point where a rider stands on a bike. Be aware when comparing standovers from brand to brand; some companies use differing standards.
Rider height range, typical: Choosing a bike size based on height is not wise. We include height ranges because it is a standard industry practice. If you need help deciding what size you should ride, visit a bike fitter to determine your ideal size. Seven does not offer size recommendations remotely. Including size ranges also highlights that most riders could choose from three Rider Ready sizes — as opposed to one for most stock bike alternatives.
Total ride weight range, average: This is our recommendation for optimal ride performance. However, if your total ride weight^[9] is above the recommendation, the bike will still handle and perform significantly better than any stock bike. For specific component weight limits, check with the manufacturer.
Total ride weight includes the rider, the bike, and carry weight. Carry weight includes all on-bike clothing, equipment, tools, hydration, food, saddle bag, and any other items that weigh something. The total carry weight averages about 14 lbs. for a 3 to 12-hour self-sufficient early summer ride. To determine total ride weight add the rider's naked body weight plus raw bike weight (about 16 to 21 lbs.) plus carry weight (about 9 to 16 lbs.).

Navigate: All MantaRays Parts Kit Frame Geometry Tubeset Options Frameset Specifications Order

The MantaRay's Titanium Tubeset Options

The MantaRay's unique design required an entirely new tubeset design. After nearly four years of development, a new class of base tubes, and our new Inverse Butting process, The MantaRay's FSO tubeset designation signifies the most radical frame kit we've ever offered.

Tubeset designation	GRC Adventure FSO Tubeset	GRC Competition FSO Tubeset
Why choose this tubeset?	Best value and toughness. $800 less than our Competition FSO tubeset. Excellent for when you're in unknown territory and need the toughest steed. Good for larger riders. Understated aesthetics.	When in doubt, choose our Competition tubeset. Balanced. Most capable over the widest range of use. Choose when a lightweight bike is important. The best harmony of all possible features. Seven's most popular tubeset choice. $800 upgrade from our Adventure FSO Tubeset
Tubeset type	Fractional Butted tubing: Seven has more than 20 tube diameters and walls to start with. Our Fractcional Butting fine-tunes the ride and performance without reducing the frame's toughness.	Butted tubeset: Lighter than our Adventure tubeset. Machined for strength, durability, and lightweight. All of this adds to the cost.
Considerations	Heavier frame. Typically by about 170 grams (6 ounces). Generally between 1,360 to 1,700 grams (3 lbs, 0 oz to 3 lbs, 12 oz) depending on frame size.	Frame price is about 20% higher.
Not recommended for	Not applicable	When price is the primary consideration.

MantaRay tubing options — Some of the 26 sizes of titanium tubes to start the process. Next, we do secondary operations on every part in each Rider Ready tubeset. Each of the 12 frame sizes gets a distinct tubeset. More tailored for more performance. This is what Seven means by "size-specific."