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My guess is a lighter frame
Might be flexy (two slim pivots on a long structure, granted, it could be triangulated), heavy, the loads are very one-sided with the shock only on one side. With bikes needing to be relatively light and still stiff and strong, triangulation is your friend. This goes against that completely.
The floating brake link appears to be completely parallel, so there should be no braking influence, except the system dropping into the travel during braking because of the rearward axle path, which the braking force on the ground would pull back. It doesn't matter if the link is above or below, it's the rotation of the brake link that matters.
And I'm not really sure you'd want that small of a radius on the arc of the axle path... Due to long swingarms used on bikes the arcs have a much longer radius. With the swingarm being longer and all
Such a short arc makes the suspension behave differently in different parts of the travel though in this case at zero travel and sag you have a lot of rearward travel with more or less vertical travel deep in the travel. Which is actually something that makes sense (good small bump sensitivity over rocks/roots and very vertical response on larger hits, which are usually drops and the like).
https://www.maxxis.com/catalog/tire-593-140-shorty-gen-2#
"After gathering years of data and feedback from our World Cup Downhill and Enduro World Series athletes, the Shorty is completely new for 2021. The knob layout has been altered to improve wet traction, cornering performance, and mud shedding abilities. The narrower 2.40" casing improves frame and fork clearance for when things get really sloppy and reduces weight."
Anyone know how their Knolly lawsuit is going?
BTW; top left corner, it says 2019.
It was a helpful point as it made it clear to me that for a trail bike, even a very aggressive one, I don't want an HP bike.
For a DH bike, it's the only way to go imo.
HP is the holy grail as far as suspension performance goes. But in terms of efficiency, weight, cost & maintenance it obviously has some Cons. For me, the only one of those I care about is the efficiency but it's a big one and I'm definitely no Pro XC racer.
Then the efficiency is dependant on sprocket size, as it's determined by the amount of link rotation - smaller sprockets, more rotation, more losses. That's why roadies use oversized pulleys in rear derailleurs. To lower the link articulation (and to spin the bearings slower too). The 99 % and 98 % are just a number, I'm confident in that even without any tests performed, based off logic and based off other friction tests (where losses, as mentioned, are over 1 % on standard drivetrains, it's more like 3 %).
Regarding HPP and idler issues, I think it could be solved with a bit of a paradigm shift. Coupled with a gearbox (with a non-concentric output compared to the BB axle) it's a non-issue (except for the drag in the gearbox). There will probably be a lot of development in this area, but 15T idlers are a simple first solution, not the ideal solution.
The lack of antisquat is also not true, why wouldn't it have antisquat? You can design negative or hugely positive antisquat characteristic in basically any suspension design, with idlers it's even easier if anything. It's just the idler position, if it's mounted to the front triangle (it gets complicated mounted to the swingarm or link, but more or less the same). The catch is with chain driven vehicles there are two antisquat components, one from the suspension geometry and the other from the chain. The chain pulling the suspension around gives you a certain level (adds antisquat with most standard layouts), while I'm not up to speed with the values, it's possible you have to take away the AS with the chain on high pivot bikes, depending on the pivot height. Because you also have the geometric antisquat, derived from the suspension geometry. If the pivot point (instant centre for multilink suspensions) is below the rear axle, you will get induced squat. If the pivot is above it (high pivot), you will get jacking when providing power to the rear wheel as it will want to fold under the BB.
So high pivot bikes have high inherent antisquat from the geometry with the chain fine tuning that. With standard layouts, you usually have low antisquat values with the chain adding a lot of it to make things work.
As for the angles, I'll leave alone the headangle as I have some thoughts on that that I would like to try out at some point if possible, but steep seat tube angles are a god send. Caveat, I'm tall, I'm 190 cm (6ft 3 or something) and I ride a 522 mm reach XL bike. I was previously on a Large Reign 2015, which was too small, but crucially, the seat tube angle was very slack (sub 70° actual). With tall riders, with the seat raised, the bent seat tubes give you a VERY slack actual angle, throwing you off the back, pedaling forwards, not downwards. So steep angles FTW. The issue with that is that you still need a given top tube length, otherwise you'll be cramped pedalling. Sure, loads of people say 'I don't care how it pedals, it has to rip on the downs'. Cool. Buy a DH bike. If you pedal your bike, you spend 90 % of a ride pedalling it (except when shuttling, where... DH bike argument). You adapt the fit to the largest percentage, it's the only thing that makes sense. So with steep seat tube angles, you get long reaches for decent top tube values.
Here's a kicker. Privateers and Poles are insanely short in the largest sizes! In the cockpit length metric. The largest Privateer is between the M and M/L size of my Bird in regards to the top tube length. And I've sat on an L version of my Bird and it's insanely short (though admittedly I'm used to a long bike...). I will be testing an XL Hightower (the XXL is very identical to my XL) to test things out, but yeah... Maybe people want a too slack bike, but most people buy bikes that are too small/short. Seen time and time again.
Yeah, longer bikes are a bit more cumbersome. Going from the Giant to the Bird I gained 75 mm on the wheelbase and 29" wheels. It is noticeable ont he really tight stuff (between the trees), but overall the performance of the bike is MUCH better allround. Even on the climbs. And tight switchbacks are not a case of an impossibility on the Bird and easy on the Giant, I just actually started to learn to do front pivots, otherwise it's kinda the same. The main disadvantage I found is relatively tight (180°) berms, where the angle of attack because of the larger wheels and the longer wheelbase changes so much, that I feel my front wheel trying to fold under me. But we're talking about a hairpin over a width of less than 4 meters, so REALLY tight and smooth berms.
mullet wheel setups in general are really awesome too, I’ve ridden my buddy’s specialized demo race which is a mullet (same setup as Bruni) and the cornering ability of mixed bikes is unmatched. So much front end grip paired with a nimble little back end means you can come thru turns at Mach 10, kick the rear end out, and then hook back up without losing any speed
As for geometries, to play the devil's advocate, my 4th ride on the ultra long bike, just riding along, getting to know the bike, was 4 seconds of my PB on my local trail. From that point on PBs and KOMs started falling. So... And it's a 150 mm bike BTW.
But notice that I never mentioned racing, I specifically mentioned pedalling. Meaning general riding, which is something most people tend to do.
The recent sb115 vs spur does a pretty good job of
Highlighting the pros and cons of modern geo. I think more conservative numbers are really great if you don’t have a lot of elevation change or care as much about the ups as you do the downs. But modern geo is just much better at going down. I do think there is a limit to how long you want to make a bike. I would also say that for hard tails I do not like modern geo at all. I’m riding way off the back if it’s steep or rough to use my legs as suspension. I feel way too stretched out as a result.