Archive: RocketMAX Gen1
Discontinued, superseded by Gen2. This page is kept as an archive record for owners and for anyone researching an older Cotic RocketMAX.
Years of production: 2016-2017
The RocketMAX Gen1 was the first big-wheeled Rocket. See the RocketMAX archive for the later generations, and the Rocket archive for its 27.5" sibling.
The RocketMAX took the high-speed ability of the Rocket and pushed it further. It kept everything that made the Rocket a proven race bike and went bigger: 140mm of droplink rear travel, built around 140 or 150mm forks at launch, and later retested and approved for 160mm forks.
MAX by name. The RocketMAX ran either 29" wheels with tyres up to 2.5" wide, or 27.5 Plus wheels with 2.8" tyres. Plus tyres rolled fast and gave extra grip and security for a small weight penalty. The 29" setup opened up a huge choice of tyres for every condition and purpose.
As a 29er, the RocketMAX proved its speed early. The Cotic Racing team took multiple UK Gravity Enduro and PMBA Elite podiums on the prototypes, and raced them in the Enduro World Series.
droplink suspension. The RocketMAX used Cotic's droplink layout, a linkage driven single pivot with a strong progression rate. The front end was Reynolds 853 for strength and durability, with a custom heat treated cromoly seat tube giving a very stiff base for the suspension pivots. The seatstays were steel too, which kept them slim for ankle, heel and calf clearance, and the droplink pivot hardware was custom ultra slim titanium. The swingarm was 7000 series aluminium, with CNC machined parts threading through the space between tyre and chainrings to put as much structure as possible into the brace area for rear end stiffness.
The details were all covered: Boost148 bolt thru rear end, taper steerer compatible head tube, ISCG05 mounts, sealed, capped and shielded pivots, precisely located hose routing, semi-internal gear routing, and both internal and external dropper post routing.
In short, it was an all round trail, all mountain and enduro bike: fleet footed, smooth rolling and grippy on the climbs, with a let's-do-this attitude on the way back down. Just as happy weaving through trees, chasing a stage time or flat out on an uplift day.
Finishes and sizes
- Finishes: Gloss Fast Red, Gloss Bright Green
- Sizes: Medium (17.5"), Large (19"), XL (20")
- Weight: 31.3 lbs for a Gold spec complete bike, without pedals
Frame details
- Cotic OFI (Optimised Fit Interface) bike fit with a long cockpit, a corrected seat angle for dropper posts and a carefully placed BB to combine stability with a fun, interactive feel
- Reynolds 853 Ovalform and DZB tubed front end brings precision, durability and strength
- 44mm standard head tube designed with an external bottom cup for taper steerer compatibility and a zero stack top cup for minimal stack height
- Custom Cotic designed 35mm heat treated cromoly seat tube for super stiff support for the main suspension pivots
- 31.6mm seatpost size is dropper seatpost compatible, with both external and internal Stealth dropper remote routing
- ISCG05 mounts on a regular threaded bottom bracket bring drivetrain security and reliability
- Rear mech cable routed internally through the steel seatstay for clean lines and low noise
- 2x drivetrain compatible: routing and swingarm clearance for double chainsets and a Shimano Side Swing front entry front mech
- 7005-T6 aluminium swingarm with a Syntace X-12 Boost148 x 12 rear axle for maximum wheel stiffness with bigger wheels
- 15mm pivots for the BB and droplink, with a thru axle style linkage clamp, keep the frame solid front to rear
- Clearance for big tyres: 29 x 2.5" or 27.5 x 2.8" Plus
- 1 bottle mount
- Geometry for speed, fun and interaction using 140 or 150mm forks: 66.5° head angle and a low 13.5" BB with a 140mm fork. Later rated and retested for use with a 160mm fork
- 140mm of Cotic droplink suspension
Geometry
The chart is a guide to frame size. OFI geometry means the frames are low and long, with plenty of standover. You can take this two ways: a regular position with a small, chuckable frame, or the next size up for a long, racey position with a short stem. Check your leg length if you upsize: you may not be able to fit a 150mm drop dropper post. All measurements are static. Frame rear wheel travel is 140mm with every fork.
140mm fork
| Frame Size | Medium | Large | XL |
|---|---|---|---|
| Seat Tube (centre-top) | 440mm | 480mm | 505mm |
| Top Tube Length (effective) | 616mm | 636mm | 652mm |
| Head Angle | 66.5° | 66.5° | 66.5° |
| Seat Angle | 73.6° | 73.6° | 73.6° |
| Chainstay Length | 447.8mm | 447.8mm | 447.8mm |
| BB Drop | -26mm | -26mm | -26mm |
| Head Tube Length | 110mm | 120mm | 130mm |
| Reach | 434.1mm | 450.6mm | 463.3mm |
| Stack | 619.8mm | 628.9mm | 638.1mm |
| Wheelbase | 1194mm | 1218mm | 1235mm |
| Usual Height Range | 169-180cm | 178-190cm | 183-195cm |
| Stem Length | 30-60mm | 30-60mm | 30-60mm |
150mm fork
| Frame Size | Medium | Large | XL |
|---|---|---|---|
| Seat Tube (centre-top) | 440mm | 480mm | 505mm |
| Top Tube Length (effective) | 597mm | 633mm | 648mm |
| Head Angle | 66.0° | 66.0° | 66.0° |
| Seat Angle | 73.1° | 73.1° | 73.1° |
| Chainstay Length | 447.8mm | 447.8mm | 447.8mm |
| BB Drop | -21mm | -21mm | -21mm |
| Head Tube Length | 110mm | 120mm | 130mm |
| Reach | 430.6mm | 447.1mm | 459.8mm |
| Stack | 622.8mm | 631.9mm | 641.1mm |
| Wheelbase | 1198mm | 1222mm | 1239mm |
| Usual Height Range | 169-180cm | 178-190cm | 183-195cm |
| Stem Length | 30-60mm | 30-60mm | 30-60mm |
160mm fork
| Frame Size | Medium | Large | XL |
|---|---|---|---|
| Seat Tube (centre-top) | 440mm | 480mm | 505mm |
| Top Tube Length (effective) | 600mm | 636mm | 651mm |
| Head Angle | 65.5° | 65.5° | 65.5° |
| Seat Angle | 72.7° | 72.7° | 72.7° |
| Chainstay Length | 447.8mm | 447.8mm | 447.8mm |
| BB Drop* | -19mm | -19mm | -19mm |
| Head Tube Length | 110mm | 120mm | 130mm |
| Reach* | 427.6mm | 444.1mm | 456.8mm |
| Stack* | 626.8mm | 637.9mm | 647.1mm |
| Wheelbase* | 1205mm | 1229mm | 1246mm |
| Usual Height Range | 169-180cm | 178-190cm | 183-195cm |
| Stem Length | 30-60mm | 30-60mm | 30-60mm |
* Marked as provisional on the original 160mm fork chart.
Not sure about sizing for a used frame? Email size@cotic.co.uk with details of what you ride now.
Component sizes
- Seatpost diameter: 31.6mm (380mm long minimum)
- Front mech: 34.9mm, Shimano Side Swing high clamp only
- Bottom bracket width: 73mm
- Bottom bracket thread: conventional English/BSA
- Chain guide mounting: ISCG05
- Fork: originally specified at a maximum of 150mm travel (561mm axle-crown, unsagged); later retested and approved for 160mm forks
- 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: 200 x 57
- Shock fittings: 15.75 x M8 down tube end, 19.0 x M8 seatstay end
- Dropper post routing: external under the top tube, and Stealth via the down tube
- Rear brake mounting: I.S., compatible with rotors up to 203mm
- Maximum tyre size: 29 x 2.5" or 27.5 x 2.8"
Setup guide
Sag. droplink suspension works best with 25-30% of the travel as sag, and 30% is our preferred starting point. The RocketMAX Gen1 uses a 57mm stroke shock, so aim for 15-17mm sag at the shock (start at 16mm). At the front, aim for 20-25% sag: 28-35mm on a 140mm fork, up to 32-40mm on a 160mm fork.
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. 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.
Cane Creek base tunes (all relative to fully open):
- DB Air IL: 1 large volume spacer, HSC 0.5 turns, LSC 4 clicks, HSR 1.0 turn, LSR 2 clicks
- DB Coil IL: HSC 1.0 turn, LSC 5 clicks, HSR 1.0 turn, LSR 2 clicks. If you have a used frame with a coil shock, contact us for spring rate advice. Do not add more than 2 turns of preload: the spring can coil bind at bottom out and damage the frame
- DB Air CS: 1 large volume spacer, HSC 0.5 turns, LSC 4 clicks, HSR 1.0 turn, LSR 2 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. 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.
Development history
The RocketMAX was developed on prototypes raced by the Cotic Racing team, taking multiple UK Gravity Enduro and PMBA Elite podiums and racing in the Enduro World Series before the production bike launched.
It launched rated for 140 and 150mm forks. During production the frame was rated and retested for use with a 160mm fork, and the geometry chart was extended to cover it.
Photo gallery
