Archive: RocketMAX Gen3
Discontinued, superseded by Gen4. This page is kept as an archive record for owners and for anyone researching an older Cotic RocketMAX.
Years of production: 2020-2022
See the RocketMAX archive for the other generations.
The RocketMAX Gen3 was Cotic's big wheel, 29er steel full suspension enduro bike: 160mm rear travel matched to a 160mm fork.
The fastest bike in the range, built for the rockiest descents and the steepest technical trails. Its Cotic developed Reynolds 853 frame and Longshot geometry carried speed through lines that would have been a fight on other bikes, with the stability and precision to stay composed on any gradient, and it still pedalled back up happily.
What was new for Gen3
Gen3 was an evolution of the Gen2 RocketMAX, the first RocketMAX with Longshot geometry. It was the longest travel 29er Cotic had made, with rear travel up from 150mm to 160mm to balance the 160mm fork. The progression rate was tweaked, the leverage ratio reduced and the window of performance broadened, and the frame was designed around big can, metric sized air shocks for a smoother feel and more tunability. The result was a more composed, planted ride through rocky sections, with the same supportive, shape-holding working edge in steep terrain.
The geometry was carried over from Gen2, adjusted for the extra travel so the handling kept the same mix of precision, stability and responsiveness. The seat angle was made 1° steeper for steep climbs and to suit the new frame rate. The tubeset gained Cotic's HD down tube, developed with Reynolds for Cotic's exclusive use: tougher and stiffer than the original, but no heavier.
On the builds, Gen3 added the RockShox Lyrik Ultimate as a fork option, plus Shimano XT and SRAM Guide RSC G2 4-piston brake choices.
Reviews
Enduro Mountainbike Magazine (Gold XT build): the testers praised the frame's looks and details, from the ovalised Reynolds 853 top tube to the cable routing, were surprised how nimble it was on climbs despite its long proportions, and rated it a match for bikes like the YT Capra, Nukeproof Mega and Specialized Enduro. Read the review.
BikeRadar, 4/5, 2021 Enduro Bike of the Year (Silver build): the reviewer found it more composed and comfortable in rough terrain while staying engaging and full of feedback, easy going on climbs thanks to the steep seat angle, roomy cockpit and calm suspension, and at 15.12kg it was the lightest bike in the test. Read the review.
Finishes and sizes
- Finishes: Army Green, Navy Blue
- Sizes: Small (390mm), Medium (425mm), Large (460mm), XL (495mm)
Origin: UK and Taiwan
Like Gen2, the RocketMAX Gen3 was designed and tested by Cotic in the Peak District, with Reynolds 853 front triangles built by Five Land Bikes in Scotland and droplink rear ends from Cotic's suppliers in Taiwan, with final checks and assembly at Cotic HQ. Singletrack published a feature on how these UK made frames were built.
Frame details
- Cotic Longshot geometry, designed for very short 35mm stems for responsive steering with high speed confidence
- Reynolds 853 front end with Ovalform top tube and Cotic exclusive HD down tube for precision, ride feel, durability and strength
- 44mm standard head tube with an external bottom cup for taper steerer compatibility and a zero stack top cup for minimal stack height
- Custom Cotic designed 35mm Reynolds 853 seat tube for super stiff support for the main suspension pivots
- 31.6mm dropper compatible seatpost size, with internal Stealth dropper remote routing
- Integrated top chain guide and a regular threaded bottom bracket (see component sizes)
- Rear mech cable routed internally through the steel seatstay for clean lines and low noise
- Custom forged swingarm heads for stiffness and tyre clearance
- 6066-T6 aluminium swingarm with a Syntace X-12 Boost148 x 12 rear axle
- 15mm pivots for the BB and droplink, with a thru axle style linkage clamp
- 1 bottle mount
- Clearance for 29 x 2.5" tyres
- Optimised around 160mm forks
- 160mm of Cotic droplink suspension with a strong progression rate
Geometry
The chart is a guide to frame size. Longshot geometry means the frames are low and long, with plenty of standover. We recommended the size for your height on the chart, with a short 30-35mm stem. Consider your leg length too: if you upsize, a long dropper may not fit, either because the collar hits the seat tube top or the post bottoms out on the droplink pivot.
160mm fork, 29" wheels
| Frame Size | Small | Medium | Large | XL |
|---|---|---|---|---|
| Seat Tube (centre-top) | 390mm | 425mm | 460mm | 495mm |
| Top Tube Length (effective) | 596mm | 622mm | 648mm | 676mm |
| Head Angle | 63.5° | 63.5° | 63.5° | 63.5° |
| Actual Seat Angle (720mm BB-saddle) | 75.8° | 75.8° | 75.8° | 75.8° |
| Actual Seat Angle (815mm BB-saddle) | 75.5° | 75.5° | 75.5° | 75.5° |
| Chainstay Length | 448mm | 448mm | 448mm | 448mm |
| BB Drop | 27mm | 27mm | 27mm | 27mm |
| Head Tube Length | 100mm | 110mm | 120mm | 130mm |
| Reach | 443mm | 467mm | 490mm | 515mm |
| Stack | 620mm | 629mm | 638mm | 647mm |
| Wheelbase | 1234mm | 1262mm | 1290mm | 1319mm |
| Usual Height Range | 160-170cm | 169-180cm | 178-188cm | 186-195cm |
| Stem Length | 25-45mm | 25-45mm | 25-45mm | 25-45mm |
| Frame Wheel Travel | 160mm | 160mm | 160mm | 160mm |
| Max Rear Tyre Size | 29 x 2.5" | 29 x 2.5" | 29 x 2.5" | 29 x 2.5" |
| Maximum Seatpost Insertion (incl. actuator) | 164mm | 199mm | 235mm | 270mm |
All measurements are static, based on a 160mm travel fork with 571mm static length.
160mm fork, mullet (29" front, 27.5" rear)
| Frame Size | Small | Medium | Large | XL |
|---|---|---|---|---|
| Seat Tube (centre-top) | 390mm | 425mm | 460mm | 495mm |
| Top Tube Length (effective) | 598mm | 624mm | 650mm | 678mm |
| Head Angle | 63.8° | 63.8° | 63.8° | 63.8° |
| Actual Seat Angle (720mm BB-saddle) | 75.4° | 75.4° | 75.4° | 75.4° |
| Actual Seat Angle (815mm BB-saddle) | 75.1° | 75.1° | 75.1° | 75.1° |
| Chainstay Length | 448mm | 448mm | 448mm | 448mm |
| BB Drop | 33mm | 33mm | 33mm | 33mm |
| Head Tube Length | 100mm | 110mm | 120mm | 130mm |
| Reach | 439mm | 463mm | 486mm | 511mm |
| Stack | 625mm | 634mm | 643mm | 652mm |
| Wheelbase | 1224mm | 1252mm | 1280mm | 1309mm |
| Usual Height Range | 160-170cm | 169-180cm | 178-188cm | 186-195cm |
| Stem Length | 25-45mm | 25-45mm | 25-45mm | 25-45mm |
| Frame Wheel Travel | 160mm | 160mm | 160mm | 160mm |
| Max Rear Tyre Size | 27.5 x 2.8" | 27.5 x 2.8" | 27.5 x 2.8" | 27.5 x 2.8" |
| Maximum Seatpost Insertion (incl. actuator) | 164mm | 199mm | 235mm | 270mm |
Mullet figures are static, based on a 160mm travel fork (571mm static length) with a Works Components 1° angleset fitted to steepen the head angle.
Maximum seatpost insertion leaves 25mm clear below the actuator for a hose or cable to route through the frame. Your post may need more or less, and an externally routed dropper won't need this margin. Cotic doesn't develop its bikes around a specific fork offset: it's down to rider preference. Not sure about sizing for a used frame? Email size@cotic.co.uk.
Component sizes
- Seatpost diameter: 31.6mm (380mm long minimum)
- Front mech: not applicable, 1x drivetrains only
- Fork: maximum 160mm travel, 573mm axle-crown (unsagged)
- Bottom bracket width: 73mm
- Bottom bracket thread: conventional English/BSA
- Chainline: 52mm Shimano / 53mm Boost for up to 32t round or 30t oval; 55mm Shimano for up to 36t round or 34t oval
- Chain guide mounting: ISCG05 bottom two tabs, plus the integrated Cotic x OneUp Components Top Guide (supplied with the frame or bike)
- Headset: 44mm for taper steerer forks: Hope 2H, Cane Creek ZS44 top/EC44 bottom, Chris King Inset I7
- Rear hub: Boost148 x 12 bolt through
- Rear axle: Syntace X-12
- Rear mech hanger: Syntace X-12 Type 1 (conventional or Shimano Direct Mount)
- Shock: 230 x 62.5, air shock only (60mm stroke also works)
- Shock fittings: 15.75 x M8 down tube end, 24.0 x M8 seatstay end
- Dropper post routing: Stealth via the down tube
- Rear brake mounting: I.S., compatible with rotors up to 203mm
Owner's manual: download the Cotic droplink Longshot user manual 2021 (PDF).
Setup guide
Sag. droplink suspension works best with 25-30% of the travel as sag, and 30% is our preferred starting point. The RocketMAX Gen3 uses a 60mm (Fox) or 62.5mm (Cane Creek and RockShox) stroke shock, so aim for 16-19mm sag at the shock (start at 18mm) and 32-40mm at the 160mm fork (start at 36mm).
Setting shock sag. Start with 170psi in the shock and any lockout or climb switch off. Ride in full kit, with your pack and water if you carry them, saddle at full pedalling height. Bounce on the saddle to work the shock, stop, slide the o-ring against the seal, then sit on the bike with your feet off the pedals and get off gently without compressing the shock. Measure from o-ring to shock body and adjust pressure until you hit your target.
Setting fork sag. Then check the fork, aiming for 20-25% sag. Ride slowly with the saddle dropped, slide the o-ring to the seal while rolling, stand into an attack position, then sit back and roll to a stop without braking hard. Measure, adjust, and recheck the rear. Repeat until both ends are right. Because weight distribution varies with saddle position, stem length and bar width, always set up by sag measurement, not a generic pressure.
Base tunes (all relative to fully open):
- Cane Creek Kitsuma Air: 1 large volume spacer, HSC 0.5 turns, LSC 3 clicks, HSR 0.5 turns, LSR 1 click
- Fox Float X2: 1 x 0.6" volume spacer, HSC 1 click, LSC 4 clicks, HSR 2 turns, LSR 5 clicks
Other shocks. Start with rebound 3 clicks from fully open, and add damping only if the bike kicks you out of the saddle or springs back too hard off drops. Run compression or pedal platform off or at minimum: droplink is designed to pedal well without it.
Fork damping. Start rebound mid-range, then go faster until it feels sketchy and back off one click. Run high speed compression fully open or close to it, and add a volume reducer rather than damping if you use the travel too easily. Start low speed compression mid-range: reduce 3 clicks if it feels chattery, add 3 clicks if it dives under braking or on steeps.
A bit of advice. Don't set rebound with the bounce-in-the-street test, it leads to rebound that's too slow for grip on the trail. If you catch pedals or want quicker steering, add air and reduce sag by 1-2mm. Lap a trail you know, change one thing at a time, and keep a written base setup to go back to. Our base settings run on the lively, fast rebound side, so give them a couple of rides before changing them.
Videos
Cy told the story of how Longshot geometry was developed on the Downtime Podcast.
Photo gallery
