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SteveClimber Added a reply to Carbon rims On enduro style bike, general consensus?
9/9/2024 3:52pm I want to try carbon rims, but I prefer narrow rim widths (less than 30mm) to keep the tyres rounder, particularly the new conti tyres that are very square on 30mm rims. I just accept that I rebuild wheels once a year and always have some EX471's in the garage and buy them on discount from bikediscount.de I did see...
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iceman2058 Liked a reply to forum topic MTB Tech Rumors and Innovation
9/6/2024 1:43pm
OK, we're fully derailing this, but let's conclude the discussion anyway 😀 The pivot is NEVER going to be above the line between the CoG and the rear axle. Imagine what that bike would like like. Here are some crude drawings I made to illustrate how anti-squat works. First, we have to understand what causes the bike the squat. The force introduced by pedaling makes the rear wheel turn, pushing backwards against the ground (blue arrow below). This causes the bike to accelerate (red arrow at the wheel). Because this force is applied way below the center of mass (the...
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SteveClimber Added a reply to Tuned Mass Dampers and Mountain Bikes
9/5/2024 5:39pm But the thing is, with a damped setup the springs and dampers currently suspending the tyres already achieve a lot of what a TMD does. Drop a fully rigid bike onto the ground, now drop a DH bike, it already bounces less, and that's exactly what suspension is for (it's just over sprung as there isn't the rider mass, just...
SteveClimber Added a reply to Tuned Mass Dampers and Mountain Bikes
9/5/2024 3:44pm Awesome work mate! Love the video comparison I was reading more on Tapei 101, and this is exactly how their TMD works. Its really actually quite simple when you think of it conceptually as the mass is just absorbing energy by moving a lot, meaning the body moves less. (watch how much the weight on the right tyre moves in...
TheSuspensionLabNZ Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes
9/5/2024 3:39pm
So it took me way to long to stitch these together and export it properly, but I did this test with the tyre at 18psi and 26psi, the 18psi gave the best result. Using parts on hand like some springs around 11.8 N/mm, a 250g mass and a 600g(250+350) mass. (*edit using the 2 opposing springs halves the rate so more like 6 N/mm) The wheel alone is about 1800g so total system about 2.4kg Tyre rates are roughly 35N/mm @ 18psi and 44N/mm at 26psi BUT they are slightly progressive in the first few mm plus I trimmed the...
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SteveClimber Added a reply to Tuned Mass Dampers and Mountain Bikes
9/3/2024 10:44pm Oh I absolutely agree. I'm not trying to say countershox haven't invested the time and made a good product. But you also have to realize with it on the market, you can cut one open, copy it, and undercut them enormously if they're charging a lot for them. The product itself is simple and easy to copy. The research and...
SteveClimber Added a reply to Tuned Mass Dampers and Mountain Bikes
9/3/2024 2:26pm They're an honest company. The tech isn't expensive at all. As @TheSuspensionLabNZ noted, you could McGyver one with an Ohlins green spring, a 600g mass and a tube and some rubber for vibrations, forget a mountain bracket just zip tie that sucker on. Charging $500 just means someone else will move in and undercut you and make you look like...
SteveClimber Added a reply to MTB Tech Rumors and Innovation
9/2/2024 5:46pm The majority of commuter bikes are ebikes now, and only more sales will happen in the future. So SRAM need to bloody plug the derailleur etc into the big ass battery already so you've only got one thing to charge.
SteveClimber Added a reply to Tuned Mass Dampers and Mountain Bikes
8/30/2024 3:58pm Surely the gyroscopic effect of two heavy wheels is enough to stabilize and resist tilting? Or are we going hard and just putting a damper on everything
SteveClimber Added a reply to Proper DH helmets
8/29/2024 2:40pm I think a big reason why we don't see independent tests of multiple sizes is cost and time. It's already expensive to do extensive helmet testing, let alone doing it 3 times for each shell size. Something I'd really like to see researched is how difference in neck and core strength affect outcomes in crashes with a given helmet. Like...
TEAMROBOT Liked a reply to forum topic MTB Tech Rumors and Innovation
8/29/2024 2:31pm
Opinions are like assholes. Neither one belongs in tech rumors.
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SteveClimber Added a reply to Brake Rotor thickness vs size talk
8/24/2024 2:26pm It's 2 and 4. Larger rotors do store more heat (as there is more mass it takes more energy to heat them up) but this is a good thing. Your ebike and heavy tires will require more energy to slow down than other setups. If your talking about a system weight of 90 -> 100kg that's 11% more energy required...
ORTOGONAL555 Liked a reply to forum topic MTB Tech Rumors and Innovation
8/23/2024 3:07am
Just saw this from Wheel Based. New caliper from Shimano.
This forum topic has 30444 replies.
SteveClimber Added a reply to MTB Tech Rumors and Innovation
8/20/2024 9:35pm Yes. It's hard to see as currently they're more expensive, but the price will come down in real terms each generation whereas labour cost in general, stays constant or increases in real terms. Its why straight pull hubs exist, its why a lot of things in the automotive world are the way they are, so robots can do the assembly...
SteveClimber Added a reply to MTB Tech Rumors and Innovation
8/19/2024 4:13pm It would be very bizarre for the C frames to have cable ports and CC frames not to, my understanding was the moulds were the same and just the quality of the carbon and slight layup differences between C and CC, not that they have actually different shapes (i.e moulds). Maybe it was guerilla anti-marketing from Specialized speculating that Santa...
Kusa Liked a reply to forum topic MTB Tech Rumors and Innovation
8/19/2024 4:06pm
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This forum topic has 30444 replies.
Dave_Camp Liked a reply to forum topic MTB Tech Rumors and Innovation
8/19/2024 4:04pm
The damper is pretty consistent. Damper fluid is designed to have consistent viscosity across a wide range of temperatures… that is the whole reason to have a special oil. Plus the fact that shim valves aren’t terribly sensitive to viscosity in the first place. I’ve run these experiments on a dyno FYI- small % changes at most. Air springs on the other hand gain noticeable pressure when hot. I’m always a bit skeptical when someone complains about their coil shock becoming a pogo stick due to heat. More than likely it’s you and your (weak, non-world cup) legs getting fatigued...
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Primoz Liked a reply to forum topic MTB Tech Rumors and Innovation
8/19/2024 1:11am
The shock will get hotter, that is not a question. And they do get hotter during use, that is clear if you run your bike in the mud - it's all dried up on the shock and brakes. My point was, if the shock warming up was such an issue, shocks would have cooling fins on them already. And bikes would have air deflectors to improve cooling and the like. It currently doesn't seem to be a big enough problem to deal with or maybe not a performance gain big enough to deal with. That WC PROs suffer from this...
This forum topic has 30444 replies.
SteveClimber Added a reply to MTB Tech Rumors and Innovation
8/19/2024 1:11am The specialised demo prototype is really good point that I didn't consider. I doubt Scott are making money of the DH frame though, unless there are some bike parks I haven't seen using a Scott rental fleet (the madmen), most manufacturers struggle to sell 500 DH bikes, which barely covers the costs of the moulds, let alone profit for a...
SteveClimber Added a reply to MTB Tech Rumors and Innovation
8/18/2024 8:15pm I agree for regular Joe's, a 3-4m downhill run at normal speeds the shock will get hot and cool slowly during a shuttle or liaison to the next trail. I disagree for racing use. Shocks get extremely hot and damping profiles definitely change from heat, and definitely at WC speeds. Short of getting a frame though how much difference it...