With his latest Scott Spark cross-country full-suspension bike, Gustav Gullholm – better known as Dangerholm – has broken the nine-kilo weight barrier. The Swede describes the bike as the best he’s ever had. And that’s saying something: ten years ago, Dangerholm first made a name for himself with a tuned Scott Spark. This was followed by the world’s lightest 29er full-suspension bike. To mark the anniversary, Gullholm has treated himself to an optimised bike from the current range. In fact, despite its lightweight construction, it’s not just a showpiece. Dangerholm is clocking up plenty of trail kilometres on the bike and plans to line up at the start of several marathon races again this year.
Conclusion
At our last meet-up, I was given the chance to take this hot ride from Dangerholm for a spin myself, and I have to say: “No shortcuts” – the likeable Swede has taken Scott’s marketing slogan quite literally with his new Spark RC. No detail has been overlooked, no minor aspect has been left out. With this lightweight, tried-and-tested 120 full-suspension bike, Dangerholm has once again surpassed itself. - Jan Timmermann, BIKE editor
Dangerholm’s Scott Spark RC in detail
- Intended use: Cross-country / Marathon
- Suspension travel: 120 / 120 mm
- Wheel size: 29”
- Weight: 8.99 kg (frame size L, including GPS mount, bottle cage bolts and pedals)
Carbon frame with a high-gloss finish
Dangerholm’s latest project is based on a Scott Spark RC SL frame. This special lightweight version is also available to end customers in limited numbers and, thanks to a press-fit bottom bracket and a carbon chainstay, saves a few grams straight from the factory. In size L and including all small parts, the frame is said to weigh in at just 1,446.6 grams. With the RockShox SIDLuxe Flight Attendant shock, including the battery, the frameset weighs 1,799 grams. By way of comparison: this is equivalent to the weight of the 2017 100-millimetre model that Dangerholm used for his 7.33-kilo project. The shock covers are made from transparent material. Dangerholm has omitted the Syncros Octopus cable routing and the Save-the-Day storage compartment to save weight.
Dangerholm is world-renowned for its unpainted carbon frames. His new Scott Spark RC also does away with a coat of paint. The raw carbon finish is achieved through a six-stage sanding process using grit sizes ranging from 240 to 4000, followed by four polishing stages. The surface has a metallic sheen and is extremely smooth. Carbon is harder than paint and is more resistant to scratches. The process took five working days.
Fork, wheels and tyres
At the forefront of the Scott Spark RC by Dangerholm is an Intend Samurai XC with a raw finish, an early prototype of the production model. Gullholm fitted the upside-down fork with a Flight Attendant unit from RockShox. The electronic control unit required minimal adjustments to the fork crown using a Dremel. Including the battery, the fork weighs 1,624.5 grams.
For the wheels, Dangerholm opted for Pi Rope Light models with Duke Lucky Jack 31 SLS5 285 rims. The German manufacturer uses Vectran fibre spokes to achieve an exceptionally low weight. The set weighs just 949.1 grams. However, Gullholm deliberately opted for slightly stiffer, stronger – and therefore heavier – rims to prioritise off-road performance. With the 245 model, a wheel weight of 895 grams would even have been possible. The tyres are Tufo XC11 TR SG at the rear and XC14 TR SG at the front.
Drive and brakes
A real eye-catcher on Dangerholm’s Scott Spark RC is the Wert StW-M titanium crankset from the Netherlands, weighing just 321.6 grams. It is lighter than most carbon cranksets, yet has passed standardised enduro strength tests. A SRAM XX SL power metre supplies data to the Flight Attendant system. The Ceramic Speed BB Alpha bottom bracket is now even standard on higher-end off-the-shelf Spark RC models. The cassette and chain are from the SRAM Eagle Transmission 1987 series and feature a gleaming silver finish. The rear derailleur started out as an SRAM GX Eagle Transmission model and received a complete Hopp Carbon Parts upgrade. It now weighs just 357.7 g including the battery. Gear changes are controlled via the Zirbel ZShift 01, which is connected to an SRAM BlipBox inside the frame. The ring shifter sits on a large ball bearing, with magnets replacing the return spring.
According to our tests, the Trickstuff Piccola brakes combine good performance with minimal weight. Dangerholm uses old 3D-printed titanium brake lever prototypes, which are said to offer more grip and a better feel than carbon levers. Hopp Carbon supplies the ultra-light carbon lever clamps. Mounting bolts for the brake calipers and discs are supplied by Extralite. The Carbon-Ti X-Rotor Steel Carbon 3 brake discs feature carbon spacers.
Cockpit and dropper seatpost
Weighing in at just 76.4 grams, the Darimo IX2AL stem on Dangerholm’s Scott Spark RC is a featherweight. The minimalist computer mount is secured with 3M tape. A RadoxX Components Oknytt Ahead cap and spacers from Onyx Racing Products complement the silver finish. An Extralite Expander plug is fitted in the steerer tube. The Extralite Hyper Grips with Hyper Plugs weigh just 9.1 grams. A Darimo MTB flat bar is used, which was specially polished for the project. The handlebars are just 690 millimetres wide. According to Dangerholm, the safety features of modern cross-country bikes mean that wide handlebars are becoming less and less important.
From Spain comes the Vertical Helium Race dropper post, with 120 millimetres of travel and weighing around 330 grams. The two-position post can only be fully extended or retracted, but according to Dangerholm, it operates reliably and is easy to maintain. The Race version uses extra-thin tube sections to save weight. This isn’t an ideal fit for the new integrated Spark RC seat clamp, which presses against the tube rather than encircling it. The tuner therefore had the seat tube wrapped in carbon to achieve a consistent diameter. The seatpost itself was, of course, also reworked, sanded and polished. The dropper remote was also given a silver finish. The saddle is an older Berk Composites prototype, which Dangerholm had already used on the 7.33 kg Spark back in 2017.
Specifications and weights
- Frame: Scott Spark RC HMX-SL, size L – 1446.6g
- Suspension fork: Intend Samurai XC 120mm RockShox Flight Attendant – 1624.5g
- Suspension fork: RockShox SIDLuxe Flight Attendant – 352.7g
- Headset: Syncros with Ceramic Speed SLT bearings – 106.0 g
- Stem: Darimo IX2AL 80mm -12º - 76.4g
- Handlebar: Darimo MTB Flatbar 690mm 6º polished – 102.2g
- Grips: Extralite Hyper Grips with Extralite Hyper Plugs – 9.1g
- Controller: Zirbel ZShift01 with SRAM Blip Box – 62.8g
- Brakes: Trickstuff Piccola with prototype titanium levers – 337.8g
- Brake discs: Carbon-Ti X-Rotor steel-carbon 3 160/180 mm – 175.3 g
- Rear derailleur: SRAM GX Eagle AXS transmission with Hopp Carbon Tuning Kit – 357.7g
- Cassette: SRAM Eagle Transmission 1987 – 316.4 g
- Chain: SRAM Eagle Transmission 1987 – 250.5 g
- Chainring: Garbaruk MTB 38T – 54.8g
- Power metre: SRAM XX SL – 107.2 g
- Crank: StW-M 175 mm titanium – 321.6 g
- Bottom bracket: Ceramic Speed BB Alpha – 68.2
- Pedals: Xpedo M-Force 8 Ti – 213.4g
- Wheels: Pi-Rope “Light” SLS5 285 – 949.1 g
- Tyres: Tufo XC11 + XC14 TR SG 29 x 2.35” – 1266.0g
- Seatpost: Vertical Helium Race 120mm Custom – 334.6g
- Dropper Remote: Vertical Ignitor Control Custom – 21.5g
- Saddle: Berk Composites Prototype – 61.3 g Bottle cage: Syncros Tailor Cage 1.0 with Extralite ExtraBolt 12.1 bolts – 24.2 g
- Computer mount: Darimo – 3.7g
What do you think: how far would you go to reduce the weight of your full-suspension cross-country bike? Let us know in the comments!
Jan Timmermann
Editor