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Stromm Cycles reach for a new type of track bike designed around UCI rule changes

The Kickstarter bike with 8:1 tube profiles seeks backers to go into full production after further relaxation of 3:1 ratio rule and new longer reach rule for 2023

At the beginning of 2023, UCI announced changes to their rule book, and among them, the cycling’s governing body further relaxed the frame design guidelines around reach and handlebars/cockpits - something that has been defining bike design for decades. Now, a Kickstarter campaign by the brand Stromm Cycles is aiming to take full advantage of the relaxed rules with a new frameset designed around 8:1 tube profiles and a longer reach.

The revolutionary bike hoping to enter larger-scale production is the brainchild of Stromm Cycles - a group of American bike experts with a background in working with brands such as Felt Bicycles, 3T and Roval. The group has labelled their creation as the first bike to truly take advantage of the scrapped 3:1 frame design rule, which UCI quietly let go back in 2016, and which was more recently followed by relaxing the 3:1 rule for handlebars and the rules on reach (more on that later). 

Stromm: A Track Bike stream

Stromm Cycles say they've been thinking of a new bike design for a while, and the timing of the new rule changes was a lucky coincidence to make their vision come true on a bigger scale. 

“Now that we've got a little bit more room to play with, with airfoil sections getting much deeper, we can really optimise each of those tube shapes and even across the tubes. The top tube shape ahead of the rider is a different shape than the top tube behind the rider,” Dave Koesel, Stromm Cycles engineer, summarised the key changes. 

The revolutionary bike

Stromm: A Track Bike wind tunnel

The Stromm Cycles bike is made using Toray Composite carbon – no word on what grade of Toray carbon has been used – and the prototype model has been made to be a bunch race frame with drop handlebars. The brand says everything on the bike has been designed to achieve maximum performance gains with the rider, and although we don't have real condition data of yet, according to Stromm Cycles, the 8:1 tube shapes on this bike allow for 600 per cent or lower drag than before.

Since the 1990s, track bikes had been limited by a 3:1 ratio limit, which meant that no tube could be more than three times wider than its depth. With the new rules, the tubes can be designed up to a ratio of 8:1 - this means that the minimum and maximum overall dimensions of the tubes are 10mm and 80mm respectively. The new 2023 track cycling rules also relaxed the rider's position for bunch racing, doubling the allowed reach measurement from 50mm to 100mm. 

Stromm: A Track Bike design

Stromm Cycles has made the most of the new rules, and the most prominent feature showcasing this is the wide fork. Together with the seat stay design, the fork works to make air flow smoothly over the rider's legs and minimise the effects of wheel differences - Stromm Cycles said any well-designed wheel is fast with this frame. 

From what we can see the fork looks similar in design to the Hope track bike and we envisage a lot of others heading in that direction in the coming years with the dropping of the 3:1 rule likely to result in a lot more interesting fork shapes appearing on the road as well as the track.

Elsewhere on the bike, the tube shape changes include a sloping top tube and seat post design that should create vortices that keep the air attached to the rider's back longer, delaying separation and turbulence and thus reducing drag. 

'Ah', we hear you say, 'couldn't many of these benefits be achieved with a Kamm tail design?'

Kamm tails, which feature in most aero bike designs, use the air to effectively replicate the trailing edge of a tube of a deep elliptical tube – the actual 'tail' is cut off which helps to reduce weight for the same strength and almost the same reduction in drag. On a track bike though weight doesn't really come in to it - no one seems to be trying to make track bikes lighter so there's no other disadvantage with going with the marginally more aero full aerofoil.

Whether your tube is kammtail or aerofoil shaped though, thinner and longer shapes always tend to have a smaller CDA (coefficient of drag) and are therefore more aero – in a world of marginal gains the full aerofoil is marginally more aero, so it's a gain.

Despite the aero-engineering, this is still a bike that is not made of proprietary components, which is something that Stromm Cycles highlights. Aside from the proprietary seatpost, the bike features widely available standards, such as 1-1/8in steerer tube, 68mm threaded bottom bracket, dropouts that take common 100/120mm track axles, and an adjustable rear drop-out which uses a barrel.

Will we see this bike at Paris Olympics?

 Stromm Cycles handlebars track bike

If all of the above sounds great and you wonder where you might get yours, well, you need to wait a while. At the moment there is exactly one of these track bikes manufactured, which is the reason Stromm Cycles has launched a Kickstarter campaign to expand the production and create bikes in all sizes (from S to L). 

Stromm: A Track Bike geometry

The obvious aim for the brand would be to have the bike race at the Paris Olympics next year, but in order for that to happen, the bike must first make an appearance at the Track Worlds in August. So in essence, Stromm Cycles needs to meet its funding target (£60,000), build the bikes, get them shipped to the UK and raced in about two and a half months. 

If you’d like to contribute to making that happen, you can find the Kickstarter campaign here

Suvi joined F-At in 2022, first writing for off-road.cc. She's since joined the tech hub, and contributes to all of the sites covering tech news, features, reviews and women's cycling content. Lover of long-distance cycling, Suvi is easily convinced to join any rides and events that cover over 100km, and ideally, plenty of cake and coffee stops. 

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17 comments

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Paul J | 1 year ago
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I'd love to see some of these new age aero style track frames come in road versions - i.e. with somewhere to put front and rear brakes. If you look hard, you can find modern, aero, track-dropout frames with forks with holes for front brakes. But never anything for a rear. Eyes or internal-guides for the cables would be nice too.

The revamped Cinelli Vigorelli is the only frame close to this that I now, but it's not a modern aero design.

I'm surprised there are no modern fixed-gear / track-dropout TT frames for the road, given how suitable fixed-gears are for flat TTs, with definite watts savings in drive-train efficiency.

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OnYerBike replied to Paul J | 1 year ago
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A fixie with a front brake is road legal (the fixed rear wheel counts as a brake). I would also suggest that, unlike a velodrome where every variable is controled, even on a "flat" TT course it is often beneficial to have some choice of gears to account for e.g. slight gradients, wind direction etc.

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Paul J replied to OnYerBike | 1 year ago
1 like

Is a fixed-gear TT bike with only a front-brake legal for competition, e.g. UCI rules? What about CTT?

For the road, on my fixed-gear, I like to have both front and rear brakes - in addition to being able to control speed with the wheel. When it comes to emergency braking, I want the hand-brake - leg braking leads to less control. But I'm a regular roadie, late to fixed. Maybe just my entrenched habits.

Also, just from a hand-hold position, I want 2 hoods. So I'm going to have 2 levers anyway.  3 Might as well wire it up.

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Paul J replied to Paul J | 1 year ago
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Self answer, CTT require only front-brake for fixed-gear TT bikes on the road: https://www.cyclingtimetrials.org.uk/articles/view/11

For UCI Road racing, inc. Time Trials it appears fixed-gear is /not/ permitted, see 1.3.025 of the General Regulations. Single speed is allowed. Brakes are on *both* wheels are required.

So basically I'm after a UCI legal (front and rear brake mounts) aero frame with horizontal dropouts.

Update: Seems there are aero UCI-legal TT bikes that have horizontal drop-outs (to allow the rear wheel position to be adjusted so it perfectly fits into the seat tube cutout, for max aero). But... there are designed for normal gears, so they have 130mm wide drop outs. So standard 120mm fixed gear hub built wheels won't really work it seems.

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Veganpotter replied to Paul J | 8 months ago
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The last generation of Cervelo P series, rim brake bikes have UCI badging, horizontal dropouts and brakes. You can also race rim brake Shiv TT. Mine had UCI badging as it was from a later run of bikes. My old HED tubular track disc fit my old P2 carbon(first gen). I wouldn't wanna ride that thing on the road though. It's a very narrow rim. I did 1 road tt with it and hated cornering with it😅

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Paul J replied to OnYerBike | 1 year ago
1 like
OnYerBike wrote:

I would also suggest that, unlike a velodrome where every variable is controled, even on a "flat" TT course it is often beneficial to have some choice of gears to account for e.g. slight gradients, wind direction etc.

Maybe with a lot of wind, yeah. But there is at least a 5% range to the sweet spot for cadence, if not 10%. You can choose a gear that is perfect for the harder leg (into the wind) and spin a bit more on the other leg. Plus, you're getting probably 5W in drive train efficiency (for fixed at least).

Also, the /lack/ of ability to change down can be good sometimes. It can force you to make an effort you wouldn't otherwise. Gears let you "chicken out" sometimes, where you would have made it.

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Veganpotter replied to Paul J | 8 months ago
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If that headwind is on a false flat going uphill, you can have a huge variation in cadence from that to the turnaround. Tolerable for a very short TT but if it's an out and back over even 20km, I'm not interested in pedaling at 130rpm for a significant amount of time.

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miannini | 1 year ago
2 likes

600% lower drag.
That's terrific news! 
Suppose a bike has 1lbs of drag. -100% would equal to zero. Now -200% would mean that bike has a negative 1lbs drag value, thus propelling it forward. 600% will mean that the bike will have -5lbs of drag, which will literally tear it from your hands.
Luckly, french constructor will have time to build the bike holding station, as leaving this bike unattended will mean it will start moving forward by itself, leading to damages.
Many golden medals and records are sure to come!
Publicitarians always make my day!

*ps: interpreting the SuperSix Evo 2012 ad: "50% less weight. 15% more rigidity per modulus of weight". So...... rigidity is fixed in proportion to weight by "modulus of weight". If new bike weights half, rigidity is half. But new bike is 15% stiffer per weight. Final value: EVO is 50% + ((15% x 50%) = 7.5%) = 57.5% the rigidity of it's predecessor (which I had one and was like riding on a kitchen countertop granite slab - excessively rigid). 
Rectified ad: 2012 SuperSix EVO. Half the weight. 42.5% less stiff. 
My ad: Supersix Evo. Flexible in the right way and half as light.

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Welsh boy replied to miannini | 1 year ago
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What a stupid post, you really blew your credibility in the second sentence by not knowing the unit for measuring drag, it makes me think you made up the rest of your argument too.

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pkaro replied to Welsh boy | 1 year ago
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A drag force is often stated in units of weight rather than Newtons. It's a trivial conversion from one to the other, of course. 

The main point of the poster's argument was relating to "600%" less and he's completely correct on this point.

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wycombewheeler replied to miannini | 1 year ago
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I thought road cc already covered a bike with negative drag, this should not be news.

https://road.cc/content/news/255805-cyclewing-sail-your-bike-now-crowdfu...

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HoldingOn replied to wycombewheeler | 1 year ago
1 like

That "tail sail" reminds me of this video by Veritasium:
Tacking faster than wind

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wycombewheeler replied to miannini | 1 year ago
1 like

miannini wrote:

 the bike will have -5lbs of drag, which will literally tear it from your hands.

I don't know about you, but I am perfectly capable of holding on to things that weigh 5 lbs. I don't think that's enough to tear it from anyones hands. after all the bike itself likely weighs more than 20lbs

miannini wrote:

  leaving this bike unattended will mean it will start moving forward by itself, leading to damages.

Of course not because drag is propotional to the square of speed. so a bike a rest would have zero drag, regardless of how many 100s of percent reduction in drag there was.

Of course once it starts moving there will be a feedback loop and it will be hard to stop.

Avatar
Paul J replied to wycombewheeler | 1 year ago
1 like
wycombewheeler]<p>[quote=miannini wrote:

Of course once it starts moving there will be a feedback loop and it will be hard to stop.

Jesus, it would a runaway reaction that would quickly consume all the entropy in the universe, causing it all to collapse into a singularity.

Ye gods, this company must be stomped before they destroy us all and everything else!

 1

Avatar
cafezinh062 replied to miannini | 1 year ago
0 likes

"Flexible in the right way and half as light."  Do you mean half as heavy?

 

Avatar
hawkinspeter replied to cafezinh062 | 1 year ago
0 likes

cafezinh062 wrote:

"Flexible in the right way and half as light."  Do you mean half as heavy?

200% lighter

Avatar
Superdave replied to miannini | 1 year ago
0 likes

miannini wrote:

600% lower drag.
That's terrific news! 
Suppose a bike has 1lbs of drag. -100% would equal to zero. Now -200% would mean that bike has a negative 1lbs drag value, thus propelling it forward. 600% will mean that the bike will have -5lbs of drag, which will literally tear it from your hands.
Luckly, french constructor will have time to build the bike holding station, as leaving this bike unattended will mean it will start moving forward by itself, leading to damages.
Many golden medals and records are sure to come!
Publicitarians always make my day!

*ps: interpreting the SuperSix Evo 2012 ad: "50% less weight. 15% more rigidity per modulus of weight". So...... rigidity is fixed in proportion to weight by "modulus of weight". If new bike weights half, rigidity is half. But new bike is 15% stiffer per weight. Final value: EVO is 50% + ((15% x 50%) = 7.5%) = 57.5% the rigidity of it's predecessor (which I had one and was like riding on a kitchen countertop granite slab - excessively rigid). 
Rectified ad: 2012 SuperSix EVO. Half the weight. 42.5% less stiff. 
My ad: Supersix Evo. Flexible in the right way and half as light.

 

Apologies, the data was overly condensed into that simple bullet point.  An 8:1 foil has the potential to be as much as 588% more efficient than 3:1.  This does not mean 600% less drag.

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