Nicolai Helius AC 650b custom bike

Nicolai Helius AC 650b

We've had our first 2013 spec Nicolai frame delivered, a Helius AC 650b" and it has some great new features. Nicolai have finally updated the head tube on their frames.

For 2013, most of the suspension frames and some of the hardtail frames come as standard with the ZS44/56 flared headtube. This makes the bike compatible with both 1 1/8" standard fork steerers and the increasingly common tapered 1 1/8" to 1.5". A tapered fork can be used with a Zero Stack headset to keep the front end of the bike low, it reduces the stack height of a conventional headset by 15-20mm and is a much neater solution. We have chosen a Chris King Inset 2 for this Helius AC.

Nicolai are gradually revamping their frames. 2013 has seen some significant changes and the addition of Rock Shox Reverb Stealth compatibility keeps their frames bang up to date. The exit hole can be seen on this frame beneath the front mech band. Nicolai supply a rubber gromit to keep this hole sealed if a Reverb is not in use. There is also compatibility for non Stealth dropper posts with cable/hose guides beneath the top tube. There are also updates to the shock linkage for 2013. The 4 travel settings have now gone on the Helius AC in favour of 2 defined travel settings, 150mm (top hole) and 140mm. The frame still uses a 200 x 57mm stroke shock, we have used a 2013 spec Fox Float CTD with adjustable Boost Valve. Nicolai have also chosen to dramatically narrow the shock link, machining a beautiful pair of rockers to create the link. The upshot of this is a shorter bolt, shorter shock mounting hardware and what should be a tighter and stiffer rear end. This particular bike is virtually the ultimate trail bike build.

We have kitted it out with XTR M980 2 x 10 Speed with the new XTR Shadow+ clutch style rear mech. The gear ratios on this bike are 40/28 up front and an 11-36 cassette, this should provide ample gears for almost any terrains. The cables and hoses on the most recent Nicolai's are much tidier and there's virtually no rub points during suspension movement. The rear mech cable slots neatly through the guide ontop of the driveside chainstay. Chris King ISO Disc hubs built onto Stans Arch rims, these wheels suit the bike perfectly, a great balance between strength and lightweight.

The rear dropouts on the Helius AC are 135 x 12mm thru axle, we have equipped the bike with a SRAM Maxle but the frame does come equipped with a simple bolt as standard. To keep the weight sensible but maintain power, we have chosen Hope Race M4 brakes in the new Stealth black finish, but upgraded the hoses to black Goodridge. In my opinion, this bike is close to the ultimate trail bike, light enough for all day rides, capable enough for gravity enduro racing and tough enough to last. The German engineering in these Nicolai's may not be everyones cup of tea, but with a 5 year warranty you can bet they'll outlast almost any other suspension bike out there. These latest bikes with the machined shock link and greater standover clearance certainly 'sit' much better than the older frames.

Final Specification

    • Frame: Nicolai Helius AC 650b
    • Fork: 2013 Fox 34 Float CTD 650b
    • Shock: 2013 Fox Float CTD with adjustable Boost Valve
    • Headset: Chris King Inset 2
    • Stem: Thomson X4
    • Handlebar: Easton Haven Carbon
    • Grips: Hope Lock On
    • Seatpost: Easton Haven
    • Seatclamp: Hope QR
    • Saddle: Fizi:k Gobi
    • Gear Shifters: Shimano XTR 10 Speed
    • Rear Mech: Shimano XTR Shadow+ GS
    • Bottom Bracket: Hope Stainless
    • Chainset: Shimano XT with 34T ring
    • Cassette: Shimano XT 11-36
    • Chain:  KMC 10 Speed
    • Brakes: Hope Race M4 Stealth with Floating Rotors 183F/183R
    • Wheels: Hope Pro 2 Evo on Stans Arch EX 650b


May 16, 2014 by Neil Dunkley
Tags: Nicolai