Brutal
That's surprisingly odd to watch.
Was hoping for a Liteville 301
Isn't it scary how much the forks flex!
Isn’t it scary how much the forks flex!
And interesting how there’s comparatively little in a single crown lefty.
Shame they left the Pole one out 😈
That was fun.. The Jeffsy and the Nomad look like they’re gonna fold 😆
The hardtails are crazy how they pitch forward sucking it all up at the front.
The Norco Torrent at 2.40 is scary how much the fork gets a recoil flex. 😳
Some of those tyres look like they'd be pretty stretched after that.
Interesting that all the rear mechs hinge down and the chains go very slack.
Chain retention is good.
Isn’t it scary how much the forks flex!
Thats the part i was taking note of. Also some of the headtube area seemed to flex, but the majority of frames appeared very stiff.
Wouldn't want a much larger chainring on some of those.... 😁
All the shocks on all the bikes seem to give up the very last bit of their travel quite a long time after the majority on shock travel was used. Not sure why it’s not all used up as a smooth transition. Unless it’s the body movement of the rider causing it maybe?
Most of them have an initial bounce too before going into full bottoming out.
Must be the tyre briefly bouncing.
I’m always surprised how rigid the bottom of downtube/bb area is, but I know nothing about engineering. All the frames look tough.
Grim donut is a monster
I’m always surprised how rigid the bottom of downtube/bb area is
Going by what most people on here say, I’m more surprised that you can’t see the bars wanging up and down like a bamboo cane 😉
Rear tyre gets very close to the seat tube on the Actofive and Yeti.
Nicely handled by the Lefty!
I think it's interesting that the bikes all appear to "stall" on landing, I guess as the fork compresses and moves backwards, it's as if the rider keeps moving forward but the bike sort of stops. It would be really interesting to see some DH bikes and how much flex they get.
Blimey. Good find!...I found it both satisfying and slightly disconcerting at the same time.
Odd thought - Aside from frame materials, I wonder how much additional flex paint can take? (Ive binned frames after finding flaking paint at headtube joint)
Mesmerizing to watch... enjoyed that.
Rear suspension looks smooth in most but i do find the compression of the forks unnerving ....jerky, flexy and in seemingly the wrong direction relative to the impact 😬
Rear suspension looks smooth in most but i do find the compression of the forks unnerving ….jerky, flexy and in seemingly the wrong direction relative to the impact
Thats the limitations of tele forks. Because there is a bending moment on them then they stick in the bushes.
fadda
Full Member
Isn’t it scary how much the forks flex!
Given the enormous cantilever caused by longer travel and bigger wheels and the increased angle of impact caused by slack head angles, I'm actually surprised that they flex so little.
It is odd that as head angles have slackened that the telescopic elements of forks haven't really changed architecture to lessen the sticktion cased by impact, which must now be significant compared to the years when head angles were 75deg+.
Interesting but not very scientific. Most bikes look to be coming in at different angles and speeds, so the forces exerted on one will be a lot different to the next.
Gives a good testament to to the overall strength though - wonder how 10 or 20 yr old manufacturing designs and practices would hold up - bits of 6061 aluminium everywhere 😀
Interesting but not very scientific
Don't think it claims to be. It's just mad to watch. I wish it was even slower though.
It is odd that as head angles have slackened that the telescopic elements of forks haven’t really changed architecture to lessen the sticktion cased by impact, which must now be significant compared to the years when head angles were 75deg+.
Aye but that's kind of assuming that the force is downwards, inline with that 75 degrees. It's inwards towards the bike too which slacker angles must help with to a degree Shirley.
the fork crowns. not surprised they creak!
I'm very, very far from an expert, but it seemed to me that the bikes with the shock slung under the top tube handled the impacts better, in terms of maintaining forward momentum. Is this a thing?
Also, really demonstrated the way head angle gets slacker on FS bikes when suspension compresses and steeper on hardtails.
I wish it was even slower though.
Slow it down to 1/4 speed in the Youtube settings! Runs for 3 hours 😉
The Jeffsy and the Yeti must have some tyre size limitation before they make contact with the frame.
In the vid the Yeti tyre has no nobbles, yet see how close it gets!
I'm amazed none of them drop the chain given how much movement there is in the rear mechs. Narrow-wide chainrings must be doing their thing!
It also looks like some chain slap the ground, never thought that was a thing!
The stumpy at 1.15 seems to have a lot of frame flex (rather than fork flex - or could just be an illusion. Was impressed by the stiffness of the Spur/SIDs but again that could be expectation of one of the nicest and most expensive bike in class.
shock slung under the top tube handled the impacts better, in terms of maintaining forward momentum.
scientifically, no, the frame is a closed system and receives the force from the rear triangle however you choose to mount the shock and linkage, with all else being equal.
However... top tube shocks may tend towards a certain suspension design/curves, eg single pivots with a forward axle path at the end of their travel; compared to vpp/maestro with more vertical movement.
OR you could be seeing the link/shock moving forward, which visually convinces you they are maintaining forward momentum, althoug the front triangle and rider are no better off.
I clicked purely to see if the Grim Donut would snap, both pleased and disappointed in equal measure that it didn't...
It's how much the wheel base shortens that surprised me.
It makes perfect sense that it happens, especially as angles get slacker but I was surprised how dramatic it was.
Looked like the bounce/rebound in the tyres caused at least some of the uneven suspension compression.
The Trek (1:36 ish) still had a good inch or more left on the Zeb fork though!
Looked like the bounce/rebound in the tyres caused at least some of the uneven suspension compression.
Someone's given it a bit of thought.
Yeah the stall is fascinating, the effect of the tyre. Peter Verdone nails it.
So the tyre plays a massive role, much bigger than I ever thought, the tyre rebound causing all kinds of problem for the shock!