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Is this an adjustable tensioner?
Ballzy move. Please someone confirm that's not a rubber band holding it together.
Out of curiosity.. as this is a tech rumours page, can you please tell me in a technical term what makes other bikes good and the demo not good? Technically speaking that is.
Spesh cops a lot of hate for a company that’s always innovating, and so does sram… tall poppy syndrome? Unsure.
I had to google tall poppy syndrome. I call it big d!(k disorder.
Looks like one to me. I made myself a crude adjuster added onto the original hardware. Was working on something like the pictured one but haven't finished yet due to injuries.
My first version also seems to do the job just fine so I haven't prioritized it much, but I'm happy to find my pictures and share
The stock tensioner is pretty hokey, just a elastic cord you have to pull super tight and tighten. According to Gates tension guide you cant really get the belt tight enough. A friend has a G3 and was having issues with the belt skipping due to lack of tension when pedaling around the bike park parking lot.
The Atherton tensioner looks more like an automotive belt tensioner and I would assume provides a lot more tension on the belt....
Can you imagine how many they could sell if these were just integrated into a seatpost?
They could make literally DOZENS of dollars. Every “fast” guy at the bike park would have one.
but how would you sell that to a world of dropper seatpost users?
Downhill bikes i guess, but they usually have super slack STAs which would affect the performance I am sure.
I never thought of this until now, but actually, it seems to me the slack seat angle matches the angle of impacts from the ground pretty well. Impacts on a DH bike come up from the ground at a roughly 45-ish degree angle when you're trucking, so sliding a TMD inside the seatpost would be a pretty close match to the ideal angle. Same reason a rearward high pivot axle path feels so good on chunk vs. an axle path that rotates forward in the travel, or why we shelter our COG so far behind the front contact patch on a DH bike.
I don't know enough about this to comment, but if we're throwing around random stabs in the dark then I'd be inclined to say that if you're in chunk then the hits are going to be hitting one wheel at a time, and that's a recipe for rotation. Any hit with the rear will rotate the sprung weight forwards, making it a worse angle not a better one?
At least we know it works now when you put it on the seatpost
Integration. Put the shake weight INSIDE the dropper. Then you’ll also need the proprietary remote that raises and lowers AND turns the shake weight off and on. Like Flight Attendant.
Except most people aren't that convinced they actually do that much good anyway. So the main benefit to the consumer (bling factor and showing off in the lift line) would be nullified if it were concealed in a seatpost.
I can't help but wonder how much of the TMD is a placebo effect.. The Pink Bike article that left 2 riders not being able to tell a difference was interesting.. Factor in the mud fest they're dealing with this weekend combined with the wide variation off hits they see, what do you tune it for?
I think James Stewart summed it up best.. Racers are mental midgets. If they believe it's faster, it will be.. We've all heard Jordi talk about how simply wiping down a shock made it feel way better to some riders..
Well they are often mounted to/parallel with head tube angles which are like 63/62° most of the time. I can’t really see this angle being too drastically different.
But it has to come with a prominent sticker at least, so it’s clear from the outside that this bike goes faster 😁
Which would be the correct angle if a hit to the front wheel rotates the bike backwards.
The head tube angle. The force rotates the bike the bike around its centre of mass from the head tube angle since the fork will compress and translate any force to it's angle.
Just ignore the rider mass, as the TMD's are there for chassis stability not rider. You've got arms and legs for that.
You have mistaken my statement for a question.
Motor racing fans will probably have heard the story about Michael Schmacher being able to detect 0.5 psi changes in pressure in his tyres. I once spoke to an F1 team employee who told me they had tested the idea on their driver, also a race winner and contemporary of Schumacher's but firmly in the "number two driver" category (no, not Webber!) His feedback was very much more influenced by whether he was told the pressures had changed than whether they had changed.
Anyway these TMDs undoubtedly do more than snake oil such as the infamous anti-vibration stickers. I would like to believe that the teams that are running them have done back to back blind testing on them, because they do have the potential to make things worse if they're not set up systematically, and they're not just a sticker you can forget about.
I’d also imagine that you could even validate with sensors on the frame
I am willing to accept the fact that a top level pro is able to pick up on subtle changes that I couldn't... I know some who tell me I'm pretty sensitive to suspension changes, so to say a rider who rides at a way higher level than I ever could may very easily feel something I'd miss doesn't seen crazy to me..
I tested one made by CounterShox, but the way the Atherton frame, the seattube is kinked and the weight wasn’t low enough. Felt great on moderate grade trails, but once the trail got steep, it feels like it raised the Center of gravity too much because the weight was higher than the bars. I had better results with weight on BB on TMD mounted above the BB on lower part seat tube. A DH frame with straight seattube, and TMD at the very bottom could work, but it would have have to be custom made based on your Seatpost/frame height. Personally I was surprised to see Ronan mount it high on Seatpost. But I’m also surprised they they mount on rear axle(but I haven’t tried that yet), so could work better than I imagine.
Yes we did this test with 6-axis sensor on front axle and handlebar. It records 2000 points of data every second. To me it was very noticeable with and without, easily could be detected on a blind test.
https://www.pinkbike.com/news/first-look-countersycles-tuned-mass-dampe…
I'm not sure that data shows the TMD at the handlebar is working as expected. The accelerations at the axle should be the same for the same trail, ridden at the same speed if the the front wheel keeps tracking the ground. if the trail is ridden faster then the wheel acceleration should be higher. What I'd expect the TMD to do is transfer less of the wheel accelerations to the handlebars and rider but these figures may even show the opposite because the wheel accelerations have decreased more than the bar accelerations.
From my understanding the difference of the graphs are mainly caused by the fact that the run with the countershock was shorter (the integral/area under the curves is smaller for countershock curves).
Kane also has a great point as to what you could expect when the TMD words as expected. But additionally you would have to keep in mind that only vertical accelerations are tracked here. It might be interesting so see if the other directions stay the same or not.
There were also an interesting discussion connected to this in a comment thread started by zoolandr in the pink bike article.
Time for a TMD thread now please.
But here’s some actual gossip: apparently there’s a new TLD helmet on the way (think Fox Dropframe). Surprised no one’s been caught riding it yet
there is also one for the lowers:
https://www.bikemetrics.de/shop#!/Equalizer-Gravity/p/772086631
Just add more TMDs all over the bike and skip the extra weights? Smoothest DH bike ever! 😆