Dangerholm's Back With Another Wild Build - The Hyper Spark Project

What a time to be alive.

Incredible suspension, 1x drivetrains, dropper seat posts and carbon everything. Not to speak of how capable modern bikes are, or how many options there are to choose from. You can get yourself a great value trail bike that actually rips, or you can get yourself pretty much the same bike that's being used for World Cup XC racing if you have the wallet for it.

Sure I've had some great times on old bikes, and you can still have a ton of fun on one. The same can be said about budget friendly bikes. A hefty price tag doesn't have to mean more fun. But either way there's no denying that most bikes today are quite amazing, and especially so the tech and looks we see on the top level ones.

So with the bar set so high, how do you level up?


Background and Inspiration

From the very start there were two goals with this project: to try and build the best and fastest XC/XCM mountain bike possible while also making it the cleanest looking ever. It would be no small task to just aim for one of these, and not surprisingly it was quite the undertaking to go for both.

The first was quite straightforward though, since it mostly comes down to chassis and component choice. No stone was left unturned and in the end I bet that most would be hard pressed to find room for improvement in that spec list. Of course some things come down to personal preference, but there's no denying that this will be one fast bike. I've done some drool worthy builds in the last few years but this one pretty much has me shaking my head in disbelief, in the best possible way.

The second goal is a longer and more complex story. I really wanted to push the boundaries for how a mountain bike is supposed to look. How a mountain bike can look even. And at the heart of it all was the idea to build it with fully integrated cable routing while still keeping all functions of a modern XC/XCM race bike. This proved to be a big challenge and we have to go back five years to get to where it all started.

For me personally my interest for clean cockpits comes from brakeless BMX bikes and coaster brake café racers. There can be a lot of beauty in simplicity, and while they're far from simple that clean look is now a common sight on road bikes. There will always be a place for classic looking road bikes with external cable routing, but these new spaceship looking creations have set a new standard. Now we're so used to not seeing cables on top level road bikes that it can almost look a bit off when you see one with them.
So in 2016 I set out to build a hardtail trying to mimic the concept. I had a custom one piece handlebar combo made especially for internal cable routing, but that was pretty much how far I got. I never managed to sort out a custom steering stop needed to protect the cables and I had to give up on the project.

Fast forward to autumn 2018 and I still had the idea stuck in my head. I could envision a bike with this futuristic look and knew that I was onto something good, so I decided to give it another go, this time with a full suspension bike. A Scott Spark RC SL frame was ordered and that was the start of me spending an unreasonable amount of thought on the new project. My initial idea had been to make an internally routed Shimano Di2 shifting system, and see if I could convert a Fox iCD manual electronic suspension system to fit the new Spark frame. Are you also shuddering just thinking of the amount of cables? So was I, but luckily there was new tech on the horizon.

SRAM would soon release its wireless AXS system and Fox had their new sensor based automatic electronic suspension system LiveValve coming up. Not only promising when it came to performance but they would make my life a lot easier too. By now I was an avid Trickstuff fan (pun intended) and I got word that they were working on a prototype brake lever coupling for internal cable routing. Things were starting to fall into place.

Like so many times before, the car world was also a source of inspiration to me. Now, I'm very well aware that a bicycle can't be compared to a multimillion dollar hypercar that's the very height of engineering, design and performance. I mean I'm pretty sure that this bike costs "just" around a third of what a set of Koenigsegg carbon wheels will set you back. Without tires.

Still, I wanted to capture a bit of the same air with this bike. I wanted it to be one step above other bikes when it came to performance and just look more than what you're used to seeing, with a bit of luxury on top.


Custom Solutions

Cable integration has been done to various extent by others too in recent years. Most notably by Trickstuff who built a trail bike in collaboration with Stoll Bikes and Bike Ahead Composites, then there's Magura with their MCi system. Very interesting and well executed concepts, but especially for XC use they both left things to wish for since none of them took suspension (lock-out) into consideration. And suspension itself is one of the biggest challenges when it comes to fully integrated cable routing on mountain bikes. On a road bike you can just run the front brake hose straight through the fork and let it exit just above the brake caliper, but no such luck on a mountain bike.

For my own Hyper Spark project the idea all along was to truly make the concept complete. Not only would the brake hoses be hidden as well as possible, it would also have race ready suspension while keeping that handlebar clean. All while being 100% functional and ready to ride.

Steering Stop
When running cables internally you don't want them to get pinched and damaged from turning your handlebars too much. To counter that you need a steering stop, something that the Scott Spark frame doesn't have. So I had to figure out how to custom make one. With the head tube area being quite complex carbon layup wise, I decided not to mess with it more than necessary and instead add one on top of the frame. It was also important that it was really robust, so that in case of a hard crash I could just replace the stop pin and the system would be good as new.

I brought out the hacksaw and metal file to make a base plate out of aluminum. Resting on the top tube it was made so that it goes all the way around the head tube, adding some stack height but keeping things bomb proof. The next step was to have it bonded to the frame by wrapping it all in carbon fiber. The corresponding headset part that clamps onto the steerer tube and actually stops against the stop pin had a cover made by hand to keep things looking clean. On production bikes these are always made round to keep knees safe, but since this was my very own bike I decided to risk it a little and go for a look that better matched the frame.

What felt like countless hours was spent on getting the fit right for that cover as well as getting a perfect finish on the "new" front end of the frame. While I was at it I also modified and covered the cable ports, so by now I was way past the point of no return.


Handlebars
First of all - drilling your handlebars is generally a very bad idea. You don't want to faceplant just because of some fancy cable routing. But to make the concept here work it had to be done and all while still being perfectly safe to ride. So the handlebars were drilled and then externally reinforced, which I had professional help with. The position of the holes was chosen so that there is a little slack in the brake hose that makes it easier to work on them. It also will allow for the brake levers to move in a crash without ripping anything apart.
After a lot of finishing work you can hardly tell the difference. Another hole had to be made on the stem section, where it rests against the steerer tube, to allow for the brake hoses to exit. Luckily this is an area with lower stress, many stems don't even have any material there to start with.

Now, you can't be sure to keep the exact properties of the stock handlebar with modifications like these since it's no longer the original intended and engineered carbon layup. I do however fully trust them for my own weight and riding. But it can't be stressed enough that one shouldn't just wing it and drill handlebars.

Finally the ends of the handlebars had to be modified as well. The SRAM AXS printed circuits boards (PCB's) and batteries, used to control the shifter and dropper post, are hidden inside the handlebars. The problem is that the PCB's are a tiny bit too wide to fit inside right away, so a very small amount of carbon was removed inside the handlebar ends. To be on the safe side, the paint and clear coat was removed on the outside and replaced with another external carbon reinforcement.


Fork
Starting at the top of the steerer, here the brake hoses enter from the handlebars. To make installation a lot easier, there is a slit so that you can route the hoses inside the handlebars first and then slide them onto the steerer tube. With a big slit it can of course no longer take the clamping force from the stem, so instead of a traditional star nut you thread an insert in. Not only does it work to fasten your top cap, but being almost solid it also becomes a load bearing part of the steerer tube.

Move down a few centimeters and the rear brake hose has to exit the steerer tube and go into the frame. The same goes for the two cables that connect the Fox LiveValve system to the fork, one to the front sensor and one to open and close the damper.
Two separate holes were made, of course as small as possible, and the steerer tube was then heavily reinforced with carbon fiber.

Routing the front brake hose was a bigger obstacle than one may think. When exiting the steerer tube it can't go to the fork arch and use the existing guide, so it had to be run at the back, which was the plan all along anyway since it will make for a much cleaner looking front end. Zip-ties were out of the question so custom guides were molded in carbon and glued to the fork crown and lowers.

When the fork is compressed the hose bends in an arch to the side and slightly backwards. So while it might look like it can rub the stanchion it actually gets further away the deeper you go into the travel.


Suspension
The Fox LiveValve system is surprisingly easy to set up and truly plug-and-play. But for this special application there was one problem. The front end sensor, that detects any bumps and tells the system to open the fork, normally sits at the back of the fork arch. While perfectly functional it simply didn't look good enough and cluttered the otherwise very clean looks. So the cable was extended and I placed the sensor right next to the brake caliper instead, so that its cable could run along the front brake hose.


Paint and Finishing
The pearl white paint is called Oryx White and it's not a color taken from a hypercar but from the Volkswagen color palette actually. For being a pearl it's quite subtle and cool in its shimmering, compared to other pearl whites that have a more yellow hue. To go with the Kashima coating there are a few select logos in metallic gold.

By now you might be wondering why I do these single colors full on paint jobs with matching parts, and it's simply to bring a homogeneous look that I personally like very much. Bikes tend to be a bit all over the place, almost looking like a collection of parts. This can look great and of course gives room for endless creativity, but by painting more than just the frame it all becomes more like the bodywork of a car. It gives for a clean and sleek look that creates a whole. So to take that concept even further is the reason I even fully painted one of the seat post combos this time.

While I do love Maxxis tires I do not love the yellow tire logos. So when a friend was unboxing his new bike with white OEM Maxxis logo tires you bet I was quick to trade him. A final finishing touch was to sharpie out the orange letters under EXO and TR - the devil is in the details.

Black might have been the obvious choice for components but I decided to bring in a bit of silver too with the brakes and drive train. Silver parts can give a kind of "light" and fresh look compared to black, and it's always my favorite for drivetrain parts since down the road they won't look worn in the same way as their colored counterparts.


Components

Frame
Okay you know this one by now - the tried and tested Scott Spark RC. Here in SL version, which means it features their best carbon fiber layup (in Scott acronym language called HMX SL) and is one of the very lightest frames on the market. Going into its fifth production year it keeps the 100mm rear travel but the stock models comes with a 110mm fork, and I'm over-forking it a bit more with a 120mm front end. I'm also on a size Large this time so the 40mm longer seat tube means you won't be able to talk so much smack about my 1 meter long looking seat posts, sorry.

For chain stay protection I'm running the Scott Ransom specific ribbed rubber protector, which is a lot more quiet than the stock Spark version. You simply need to trim it a little with a pair of scissors and it sticks right on. A small but great upgrade tip for any Spark owners out there, or anyone with a bike running a similarly shaped chain stay.


Suspension
As mentioned above the Fox LiveValve system was a crucial component to make the clean looking cockpit happen. But I also chose it because of its performance. The version on this bike is based on the Nude rear shock and 34 Step Cast 120mm fork.

LiveValve is an electronic automatic suspension system. You set up sag, rebound and so on just like on a regular bike and when you switch the system on it locks your suspension. Sensors sit on each end of the bike and will detect bumps and the main unit then open the fork or rear shock individually. The amazing thing is that this whole process happens in just 3 milliseconds, which is around 100 times faster than you blink your eyes.

On the main unit, which also is the battery, you can choose from five different settings. These determine how sensitive the system will be, so you either have the fastest setting for maximum efficiency or you can go step by step to the more relaxed setting that will keep your suspension open for longer. It also detects for example free fall, so if you go off a drop your suspension will already be open when you hit the landing.


We've mostly seen the system on longer travel trail bikes so far, but personally I think that XC/XCM and snappy short travel trail bikes might be the very best application for it. Here the focus lies more on pedaling efficiency which of course is where LiveValve really shines. Perfect for racing too since you don't have to think about your suspension remote when your heart rate has been in the red zone for way too long.

Sure you might prioritize having the tuning options of a GRIP2 damper fork up front if descending is what it's all about, but I really think we've just seen the beginning of this technology. The LiveValve system opens up for many possibilities. Since it also senses the angle of the bike, it could for example be programmed to be in the most efficient setting when going uphill and vice versa on the downhills. Imagine you incorporate a GPS and you could have speed as a variable too, or even program it for a specific race course. A little bit like how if you go to certain race tracks with a Koenigsegg you can download the perfect car settings for that very track.

It's easy to shun upon new technology and tell people how you don't need it. But even in this very first version LiveValve is sure to be great for many riders and their riding style (I'd say a ton of riders if only more people could afford it), even if it doesn't 100% suit your own personal needs. But give it a few years and it might be a great thing for you too.


Cockpit
At the front you have a Syncros Fraser iC SL one piece handlebar combo. This is the "Nino Limited Edition" which is 90mm long and features a -25 degrees angle, which I'm using to counter the added stack height from the steering stop system. I'm running it at 730mm width and on top sits a neat little Garmin mount. The Grips are the new Syncros foam grips, which are not the lightest but feel a bit like a mix between traditional foam and modern silicone grips.
At the heart of it all is two CeramicSpeed headset bearings.


Brakes
Trickstuff Piccola Carbon is on braking duty. Not only the lightest brakes on the market they're also probably the most powerful in their category. The latest version features carbon brake levers as the name suggests and also has an updated caliper design.

Already from the start these brakes are promising for internal cable routing. Contrary to most other brakes, the hose exits very close to the handlebar. So for their own Stoll concept bike they developed a special banjo coupling that changes the angle of the hose. The first version was 3D printed but the current one is CNC machined. So if some sort of standard develops for brake hoses running inside the handlebars, these brakes are ready to go. You can also simply switch the coupling to a regular one if you wanted to use your brakes in a traditional setup.

I'm running 160mm Trickstuff Dächle UL discs with the option of going 180mm up front. They are fastened with Bike Ahead Composites center lock adapters which are not just the lightest ones out there but also maybe the best looking.


Controllers
Normally the SRAM AXS components are controlled via their corresponding triggers. They work very well but are quite bulky looking hanging down below the handlebars, and personally I'm not a fan of the shifter ergonomics and eagerly (eagel-y?) awaits the next generation. Luckily there is an incredibly neat alternative out there - Zirbel.

Zirbel is a Swiss company who primarily makes electronic shifting controllers. Their Twister model can be described as a mix between a trigger and gripshift. There is a trigger that's integrated into a ring that sits around the handlebars. You have one click in either direction and instead of return springs it runs with small magnets, giving it a surprisingly tactile and distinct feeling. So press down for one direction and up with the back of your thumb for the other.
They are intended to be used with a SRAM BlipBox which makes it all plug-and-play to integrate seamlessly with the AXS system. My problem was that there was already so much going on that there was no room to run more cables in order to hide a BlipBox inside the frame.

The solution became to disassemble the AXS controllers and attach the Zirbel Twister cables directly to the circuit boards. As briefly explained earlier the setup is not an easy task to accomplish for many reasons, but now the cables run under the foam grips and the PCB's and batteries sit hidden inside the handlebar.

Think those shifter ring triggers are way too small for your meaty paws or winter gloves? No worries, they can 3D print plastic shifter rings in any size or shape you want and even encourage you to do it yourself if you have your own printer.


Drivetrain
Paired to the Zirbel shifter is of course a SRAM Eagle AXS derailleur, that has been upgraded with a CeramicSpeed OSPW system. Not only do the pulley wheels spin from just looking at them hard enough, but their bigger size also means slightly less chain friction since the links don't have to rotate as much. Marginal gains for sure, but no stranger really than things like Kashima coating or the carbon outer derailleur cage that sits there in the first place.

On the topic of friction the bike has a CeramicSpeed UFO chain. They don't actually make the chain but it's all about the treatment. The chain is first perfectly cleaned and then the white low friction powder is applied. Of course how many watts you save will vary depending on what chain lube you compare it to, but it can be several watts. The coating is intended for dry conditions and will last up to 600km, essentially making this a race day chain. After that you simply continue to use it with their UFO Drip lube or any other lube of your choice. Overkill for most mortals including myself? Sure, but remember we're trying to build the best bike possible here.

The cassette is a 12-speed 10-50T Garbaruk and it's matched to a quadzilla worthy 40T Garbaruk chainring up front. The crankset is my beloved old Tune Blackfoot which looks amazing and is still going strong into its fifth riding season, while weighing just 334g. It spins on a CeramicSpeed bottom bracket and the pedals are Xpedo M-Force 8-Ti.


Seat Combos
Quite the luxury to say the least, there are three different seat combos to choose from for this bike.

First there is the dropper combo, which is based on a RockShox Reverb AXS 170mm post and a Syncros Belcarra R SL seat. By now most are familiar with the Reverb post but the Syncros seat brings some new things. Traditionally all seats are made with rails attached to a seat shell by various techniques. But on the new Belcarra the rails and shell are molded as a single piece of carbon. This is done by using special molds and a technique called resin transfer molding. Dry carbon fiber is laid up in the mold and the resin is then injected under high pressure before curing the whole piece.


Then there is the white one-piece carbon combo, a very unique collaboration between Schmolke Carbon and Berk Composites. The latter is a Slovenian brand who among many lightweight things have carbon seats as a specialty. Not yet a common site on mountain bikes, you can see their parts and shoes being used by Pro Tour road guys. German Schmolke has provided the seat tube, based on their TLO seat posts, and Berk has then made it into a full combo with one of their seat shells. What's special about this one is that it still features rails, so there's a lot of flex in the shell offering great comfort. The entire combo weighs 183g.

Finally there is the black/raw one-piece carbon combo, also made at Berk Composites. This masterpiece weighs just 133g for the whole thing, and sure looks the part too. One of the reasons it could be made so light is that it has no rails, so while there is some "wing flex" it is more rigid and offers slightly less comfort.

Why even bother with rigid combos? There's no denying that droppers are great but in many cases they're also boat anchors. Losing that much weight at the highest point of your bike actually makes it feel a lot lighter and nicer when out of the seat pedaling. So if you have some easy terrain riding or racing planned you can run a rigid one. And of course - they look super clean.


Wheels
There are many cool and great wheels out there today, but the these Syncros Silverton SL wheels that have the most incredible mix of engineering, design and performance. They are one-piece carbon wheels, so the rim, spokes and hub flanges are molded as one unit. That means that you don't really have separate spokes, but the carbon fibers go from one end of the wheel all the way over to the other. The hub flanges are then pulled apart and have the center hub piece installed, creating tension in the wheel. Weight is a 1290g claimed (this pair is 1307g) and the inner rim width is 26mm, spinning on CeramicSpeed bearings in this case.

The benefits is the low weight, of course, but it also makes for an extremely responsive wheel set. They are incredibly stiff for acceleration while offering good compliance. Perfect characteristics for a XC wheel set. What if you break a spoke? As long as the wheel isn't completely destroyed or too much out of true, they can actually be repaired by mending the broken spoke back together.


Tires and Inserts
Tires are the Maxxis Rekon Race in 2.35" width and with EXO protection. A great allrounder for most conditions while still keeping rolling resistance pretty low.

For inserts I'm running the CushCore XC version. At 150g each these aren't the lightest, but the good ride characteristics makes the weight easy to justify. Not only do they help protect the rim and tire, they also help keep the tire stable by pressing out on the tire walls. The low profile lets the tire otherwise act as it normally would. For some tracks and riding the bike will be fine in an old-school setup with no inserts but they sure help make it even more capable.


Scott Hyper Spark - Weight from 9.78kg / 21.56lbs






Either way, after so many years of work and effort I'm of course very happy about the bike being finished and it turned out even better than I could imagine. There's still room for improvement but I managed to prove the concept and show both new looks and possibilities.

But most of all I look forward to riding the shit out of it, and hopefully have a speedy mental recovery from when I first scratch it. So keep your eyes peeled for a proper bike check video here on PInkbike in spring and maybe some riding content as well.

What's next? Take the same concept to a hardtail with rigid fork, which should make for even cleaner looks. Feel free to keep up with that one and future builds via my Instagram.


Please keep in mind that any modifications such as paint stripping, repainting, sanding or in any way modify frames, components or safety equipment is potentially dangerous and can lead to crashes and injuries. It will always void any and all warranties, and is strongly advised against by SCOTT Sports and all other manufacturers, who take no responsibility. It is not recommended to put any travel fork on any frame, if unsure of the fork travel limit for your frame always consult a dealer or the brand directly first. If you choose to modify your bike anyway, always make sure to do so with safety in mind and remember the points above.

Posted In:
Reviews and Tech Bike Checks XC Bikes Scott Scott Spark Gustav Gullholm