Archive: Solaris Gen2

Cotic Solaris Gen2 in Gloss Hot Yellow

Discontinued, superseded by SolarisMAX Gen3. This page is kept as an archive record for owners and for anyone researching an older Cotic Solaris.

Years of production: 2016-2017

The Solaris is our flagship big wheel hardtail: 29er or 27.5+. Our fastest hardtail got faster: the latest thinking on bike fit and progressive handling with OFI geometry, plus 27.5+ tyre compatibility, made a fast, future-proofed, fun machine.

Handling is confidence inspiring, interactive and fun, with a planted feel at high speed on the rocks and carve-it-up traction in the corners. As always, the Reynolds 853 front triangle is all present and correct. Signature features such as the Ovalform top tube and 35mm seat tube keep weight, stiffness and durability in the sweet spot.

The result is amazing adaptability: from suspension-forked, big-barred trail warrior, to Plus-tyred, high-traction monster truck, to rigid-forked map-crossing smoothie, and everything in between.

Finishes: Gloss Hot Yellow, Gloss Gunmetal and Matte Orange.
Sizes: Medium (17.5"), Large (19") and XL (20.5").

29 or 27.5+?

29" wheels roll easily and give a lot of stability and confidence in rougher terrain, at the expense of being a little heavier than regular 27.5" wheels. They can suit taller riders better, as the way the frame is packaged around the larger wheels (longer rear end, longer wheelbase, taller front end) suits their proportions.

The 27.5 Plus option brings a wide, supportive rim in the same size as 27.5" wheels, with a wide (up to 2.8" on the Solaris) high volume tyre that ends up about the same diameter as a regular 29er wheel. It is a little heavier than 29", but you run the tyres at very low pressure (typically around 12-16psi), which gives loads of grip and comfort. It smooths the edges of rocky downhills and gives incredible rock-crawling traction on technical climbs. Plus tyres are not at their best when heavily loaded into berms and groomed features at speed, so choose the wheel type that suits you.

Frame details

Large diameter, thinwall, air hardening Reynolds 853 steel front triangle with signature Ovalform top tube
44mm standard head tube with external bottom cup for taper steerer compatibility and zero stack top cup for minimal stack height
Oversized 35mm seat tube gives great precision to the ride
31.6mm seatpost size is dropper seatpost compatible (external remote only), with hose clips for the remote under the top tube
Signature Cotic 4130 cromo wishbone stay rear end. Bridge-less S-bend chainstays with Cotic Hexten gussets for improved fatigue life
Clearance for 29 x 2.4" or 27.5 x 2.8" tyres
Minimum 100mm travel forks or 490mm rigid. Strong enough for up to 120mm forks
Cotic OFI geometry: long top tube, slack seat angle layout for inline seatposts, and short stem set-up (50-80mm stems recommended)
Sizes: 17.5", 19" and 20.5". The frames are designed to be compact and chuckable
Weight: 4.9lbs for the 19"

Geometry

The Solaris features Optimised For Inline (OFI) geometry. The original Solaris geometry was designed around an 80mm travel suspension or 470mm rigid fork as a minimum with 44-46mm offset, and assumed a layback seatpost. Running longer forks (most people used 100mm or more) shortens the reach, and running an inline or dropper post shortens the position from the other end, squeezing the room available to the rider.

OFI takes the rider position and BB height originally intended for 100mm forks and maintains it with 120mm forks and an inline seatpost, so rider position is better for both fork travels now that the 80mm option no longer has to be accounted for. The head angle was also slackened to allow for the emergence of 51mm offset forks. You can happily use either offset (46 or 51mm).

120mm travel forks

Frame size	Medium	Large	XL
Seat tube (centre-top)	440mm	480mm	520mm
Top tube (effective)	614mm	631mm	657mm
Head angle	68°	68°	68°
Seat angle	72.5°	72.5°	72.5°
Chainstay length	442mm	442mm	442mm
Wheelbase	1141.2mm	1162.2mm	1180.7mm
BB drop	52mm	52mm	52mm
Head tube length	100mm	110mm	120mm
Reach	425.7mm	436.8mm	457.8mm
Stack	600.3mm	609.6mm	618.9mm
Usual height range	174cm - 182cm	182cm - 191cm	188cm - 196cm
Stem length	40-80mm	40-80mm	40-80mm

Measurements based on a 120mm travel fork with 20% sag (rider on board).

100mm travel forks

Frame size	Medium	Large	XL
Seat tube (centre-top)	440mm	480mm	520mm
Top tube (effective)	614mm	631mm	657mm
Head angle	68.5°	68.5°	68.5°
Seat angle	73°	73°	73°
Chainstay length	442mm	442mm	442mm
Wheelbase	1136.4mm	1151.2mm	1176.0mm
BB drop	56mm	56mm	56mm
Head tube length	100mm	110mm	120mm
Reach	432.1mm	443.2mm	464.2mm
Stack	595.8mm	605.0mm	614.1mm
Usual height range	174cm - 182cm	182cm - 191cm	188cm - 196cm
Stem length	40-80mm	40-80mm	40-80mm

Measurements based on a 100mm travel fork with 20% sag (rider on board).

Component sizes

Seatpost diameter: 31.6mm (wise to get a decent length one)
Front mech: 34.9mm band on, conventional top pull or side swing
Bottom bracket: 73mm width, conventional English/BSA thread
Headset: 44mm cup (for example a Hope 2H)
Rear hub: normal 135 x 10mm QR
Dropper post: external only, with dedicated remote routing under the top tube

Complete bike builds

Specifications as listed on the original order page. They were subject to change without notice, so bikes in photos and videos may differ. Handlebar and stem options were offered with every build (Race Face Respond bars in 785mm x 12 rise or 720mm flat; Joystick bar and stem upgrades; Race Face or Cotic stems from 35 to 70mm; Hope AM stem). Pedals were not included.

Gold 29: Shimano Deore XT M8000 1x11 with 11-46 cassette; Race Face Turbine Cinch 175mm cranks, 30t direct mount ring; Deore XT M8000 brakes, 180/160 rotors; X Fusion McQueen Roughcut HLR 120mm fork, Boost 110 x 15mm axle; Hope Tech XC wheels; WTB Vigilante 29 x 2.3" front and Trail Boss 29 x 2.25" rear, tubeless; Race Face Ride 31.6 x 375mm seatpost; Cotic Cromo rail saddle; Hope headset.
Gold Plus: as Gold 29 but with Hope Pro4 hubs on WTB Asym i35 rims and WTB Trailblazer 27.5 x 2.8" tyres, tubeless.
Silver Hope: Shimano SLX M7000 1x11 with 11-42 cassette; Race Face Affect Cinch 175mm cranks, 30t direct mount ring; Deore M615 brakes, 180/160 rotors; X Fusion McQueen RL2 120mm fork, 110 x 15mm axle; Hope Tech XC 29 wheels; Continental Trail King 29 x 2.2"; Cane Creek 10 headset.
Silver Hope Plus: as Silver Hope but with Hope Pro4 hubs on WTB Asym i35 rims and WTB Trail Boss 27.5 x 3.0" (front) and Ranger 27.5 x 2.8" (rear) tyres, tubeless.
Silver: as Silver Hope but with Shimano SLX hubs on WTB ST i25 rims.

Many parts could be customised, including disc brakes (Shimano or Hope), wheels (up to Hope/WTB Ci24 carbon), forks (Roughcut HLR or Fox 34 Factory FIT4), cassette (Deore XT 11-46 or Hope 10-44) and headset (Hope).

Development history: July 2015

We started development of the latest Solaris in response to changes in the way people set up their bikes. No one was using 80mm forks and very few used 470mm rigids, yet the original frame was designed around these as a minimum. At the other end of the scale, more and more people were using 120mm forks, which was on the limit of the geometry and a bit of a compromise for all-round riding.

We had also developed the small size Solaris, which diverged from the original geometry, particularly in head angle. Because the wheels limit how short a frame can be, shorter riders used 50mm or even 40mm stems to get a good position, so we slackened the head angle to slow the steering a little to balance that out. Three years on, most people want stems that short regardless of height. Shorter stems with longer forks reduce the reach of the frame, and the widespread adoption of dropper seatposts (usually with an inline clamp) squeezes the other end, so we felt the frame needed re-optimising. We had already applied solutions to all of this when developing OFI geometry on the 27.5 wheel bikes, so it was a matter of applying those ideas to the new bike.

OFI dictates optimising the reach for the longer fork (here, 120mm travel), so reach was reset to the length established for the original frame on 80mm forks, but with longer forks installed. We also tweaked the seat angle so it sits well for inline seatposts with the saddle in the middle of the rails for 120mm forks, while still allowing a good position with 100mm forks.

The final piece was the handling layout. Fork offsets have increased for 29er bikes: the 51mm offset that was the sole preserve of the Trek group was made available across the market three years earlier. The original frame was designed when 44mm offset was the largest available, and some 29er forks were still around 40mm like 26", which meant steepening the head angle compared to the smaller wheel bikes. A larger offset reduces trail and lightens the steering.

Paul had been instrumental in the small frame with the slacker head angle, and was convinced it could work for the larger sizes after testing the small bike with 51mm offset X Fusion forks (all X Fusion 29er forks are 51mm offset). We have a series of anglesets for the 44mm head tube our bikes use for exactly this situation, so Cy tried the 1 degree option (net 0.7 degree slacker head angle, 3mm lower BB) and the 1.5 degree option (net 1 degree slacker, 5mm lower BB) on his large Solaris with 120mm Magura TS-8 forks, which have a 46mm offset and so would also show whether slackening had an adverse effect on smaller offset forks. After back-to-back testing, everyone who tried it preferred the slacker option, and it was faster around our test loop. The geometry was measured and set from that layout, with OFI rider fit principles applied. Because you can use a short stem and wide bars without compromising fit, it keeps a lightness of touch in the singletrack that might surprise you from the numbers. It works better with 120mm forks than the previous bike and is much more at home on rough, high speed terrain. By tightening the window of operation to 100-120mm forks, it works better in both guises than the previous bike.

The last spanner in the works was Plus sized wheels. We had looked at 29+ but it involved bespoke parts and compromises we were not comfortable with, and no suspension fork manufacturers were going to support it at the time. We like our suspension forks, and not having them would have made the Solaris something quite different. 27.5+ started to gain popularity, and once WTB sent us the specs we knew it would fit, so we had to test it.

We got the wheels earlier in 2015 and were immediately impressed. The weight was good, rolling resistance surprisingly low, and the grip over rocks and in fast singletrack impressive. That they proved faster than Ardent 29er wheels on our woodsy singletrack loop was something we just weren't expecting. Given the new Solaris had slightly more clearance out back, offering 27.5 Plus as an option was a no-brainer. The main conclusion from our testing was that a lighter, narrower rear rim was definitely preferable to a much heavier wide one, but on the front we much preferred the support of the wider rim to prevent deformation when loading the front of the bike in corners. We compared a WTB KOM i25 (25mm internal) at 445g with a WTB Scraper i45 (45mm internal) at 695g as the extremes. For production we went with the WTB Asym i29 rear at 510g and the Asym i35 front at 560g, which gives the support we like on the front with a snappy feel at the back. They were available as a chassis pack option or as an upgrade on the complete bike from August 2015.

Read about the development of the original Solaris (Gen1).