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Sacki Added a reply to 2026 MTB Tech Rumors and Innovation - Longer and Slacker
2 hours ago I understand. But wingspan is also not comprehensive enough. How long is your "upper" body. Where are your arms attached to your upper body? Where are the arms relative to your feet? Soime people have short necks or long heads and, while some peoiple might have same height and wingspan, but their arms might be 5cm (or more) further away...
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FrontRangeFriend Liked a reply to forum topic 2026 MTB Tech Rumors and Innovation - Longer and Slacker
10/30/2026 4:25am
This is so cool. I’ve always wondered about this but have been too lazy to do the math myself.
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Sacki Added a reply to 2026 MTB Tech Rumors and Innovation - Longer and Slacker
3 hours ago We're talking about very complex dynamic load distribution here. I believe it is way too complex to calculate anything something universally applicable for the general rider. Mountainbikes are not ridden on even ground like race cars, wehre you know exactly what loads are to be expected in every tunr of a track. Varying slopes, obstacles (that means slope or load...
Sacki Added a reply to 2026 MTB Tech Rumors and Innovation - Longer and Slacker
3 hours ago First off: Thanks @iceman2058 for sharing this tool here. I just sent it to him one day before to have a look, when we had just put it live, and it's an honour to see it shared amongst other enthusiasts (not to say nerds), like ourselves. @thegromit We were thinking about making the frame specs also indepent between the two...
Sacki Added a reply to Why are yokes sideways?
2/24/2026 1:02am Well, the name Bike Yoke kind of already answers your question, doesn't it? 😉 We want to honour our roots, so we stuck with the name, although we are more known for other things now. The Yoke for Specialized bikes was our first product. I had previously been with Bionicon, yes. I was there from 2010-2018 as suspension and frame...
Sacki Added a reply to Stem Length
2/16/2026 11:20am I understand. You can use that to calculate the rotated back- and upsweeps based on original back- and upsweeps only. But I had to do this calculation anyway, because I added a separate calculation that gives information about reach and stack values for a trimmed bar, e.g. if you trim your bar from 800 to 760. The additonal trim calculator...
Sacki Added a reply to Stem Length
2/16/2026 7:18am I do not think you can generally break it down to what and why something turns "quicker" when you only swap stems. That very much depends on your general body positoning before the swap, too. In my opinion (and my experience with dozens of bikes changed my opinion over time) stems should be first and foremost be used for achieving...
Sacki Added a reply to Stem Length
2/16/2026 6:20am You don't need the two points that define the beginning and end of the straight portion of the bar. Any two points sitting on that straight portion (no matter where) are enough. One of the is the reach and stack point (X1/Y1) (the tip of the handlebar) as defined in our geometry. Another reference point one can be calculated (with...
Sacki Added a reply to Stem Length
2/13/2026 3:54am @Primoz It won't work with how most bars are currently measured (rise, backsweep, upsweep). Because those dimensions do not define the goemetry of a handlebar. I will not go down that rabbit hole agaion and explain why But if you have stack and reach and the sweep angles, then it will actually work, I think. I think @CascadeComponents gave me...
Sacki Added a reply to Stem Length
2/13/2026 3:00am I am not entirely sure anymore. I made this sheet a long time ago. But I believe it was because of the quadrants in trigonometry. Stems with negative length or rise, or handlebars having negative stack, head angles being more than 90° and combinations of all those theoretical possibilites, even some values keyed in as "0", would sometimes calculate unexectedly...
CascadeComponents Liked a reply to forum topic Stem Length
2/12/2026 1:19pm
I'd think simplest way to do it would be create an equation for start and end points of the straight bar section as a function of roll angle. Those two points define the axis of the straight bar section so should be pretty easy to find the angle of it relative to whatever plane you want. I believe the easy check for whether or not the equation works is a roll of 90 degrees should result in a down sweep angle that equal to the back sweep angle before the 90 degree roll.
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Sacki Added a reply to Stem Length
2/12/2026 9:05am When I started diving deeper into all of this bar and stem geometry when I designed our bars, I built myself a handy little tool to play around with cockpit geometries that takes bar roll into account. Stack and Reach is taken into account, depending on bar roll, but I have not yet found a way to calculate the sweep...
Sacki Added a reply to Stem Length
2/11/2026 4:58pm Well, I watched the video linked in the first post and I felt I needed to correct some things. In the video it is being said that you "sverve" around the steering axis rather than rotate around it. This is just plain wrong, hence my picture in my original post. Maybe this picture makes it more clear. It does not...
Sacki Added a reply to Stem Length
2/11/2026 6:24am And that is precisely, why stem length alone does not matter a single bit. My sketch was just a little brain aid that helps do away with the myth that a longer stem makes steering softer and less direct. It's far from being cmparable to a larger diameter steering wheel (where you move around a much larger radius with your...
Sacki Added a reply to Stem Length
2/11/2026 3:55am More on the topic here, too: https://bikeyoke.com/media/6e/59/d6/1741646748/Handlebar%20geometry%20e…
Sacki Added a reply to Stem Length
2/11/2026 2:13pm Here is your difference in steering bwetween a 70mm stem and a 35mm stem with straight 800mm bars. A video to make the scribbely lines more understandable: https://photos.app.goo.gl/bYf6TE4obQUwvhJG7 As you can see, the rotation diameters are virtually same (406mm vs 401mm). That's about a 1% difference. Your hands will travel about the same amount: 212mm vs. 210mm for a 30°...
pamtbr Liked a reply to forum topic The Bikeconomics (Mega)Thread
1/26/2026 12:21pm
Is the cost to host a World Cup considered Bikeconomics? Sure, why not? The Lake Placid events cost $860k in 2025 and brought in $293k in tickets, lift passes, and parking. Hotels and AirBnBs filled up, and money was spent on food, fuel, etc. I don't think the split venue and lack of bike park trails help the cause for this round, but hopefully the area and UCI decide to keep Placid on the schedule.
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Sacki Added a reply to The Bikeconomics (Mega)Thread
12/26/2025 9:53am But Zink clearly said that the were no rules in place at that time where they'd had to pay state taxes to other states. Why be bothered by such a statement, if you knew you did nothing wrong? And on the other hand: Why would YT Germany (or that banker) come up with a truly/poor lousy attempt of coming up...
Sacki Added a reply to The Bikeconomics (Mega)Thread
12/26/2025 7:48am @rgard Thanks for the explanation. That is what I imagined. I was ware of there being different sales tax for different states in the US and that there must be a way how to handle "inter-state sales". In the EU we use kind of the same system to collect VAT for international sales between EU-countries. In Germany, we have a...
Sacki Added a reply to The Bikeconomics (Mega)Thread
12/23/2025 1:14pm Can someone explain the tax thing Zink mentioned in the interview? What was it he said YT tried to threaten them with? Why would they owe them (who) taxes?