Behind the Numbers: Norco Sight

May 19, 2020 at 8:59
by Dan Roberts  
Behind the Numbers Norco Sight


Behind the Numbers is made possible by Creaform Portable 3D Measurement Technologies


Heading into round two of our Behind the Numbers trail bikes we have the 2020 Norco Sight. If you’d like to go back and see what we looked at for our first trail bike, check out the Commencal Meta TR 29 analysis.

Norco is one of the larger brands in the industry to be adopting the properly long and slack mantra that many other companies say, but don’t deliver to the degree of Norco. Their Sight was bumped up in terms of travel and size for 2020, and it points more at the aggressive, downhill side of trail bikes.

One standout feature that Norco does is evolving their geometry as the bike size changes. Dubbed Ride Aligned, there is a focus on keeping a front to rear balance for all the sizes by growing the chainstays as the front end lengthens. They even steepen the seat angles as the sizes grow to keep the rider’s weight in a more balanced position when seated. Few brands do this, and Norco deserve a tip of the cap for it.

The Sight may look like a lot of other bikes at the moment from 100 yards, and that’s mainly down to the layout. But ever since a certain patent expired, we’ve seen a lot of companies adopt this design and there are good reasons behind this that we can see from the suspension characteristics it gives.


Scanning

For the Sight, as well as the others we'll be doing in the future, we filled a van with test bikes from our local bike shop, The Factory in Fribourg, Switzerland, and headed off to Creaform’s French office in Grenoble.

Seeing as we had multiple bikes to do, one after another, Creaform’s MetraSCAN 3D was the tool for the job. The MetraSCAN is a 3D scanning solution aimed at shop floor condition in industry, where repetitive scans jobs are needed and potentially with much larger volume parts.


Behind the Numbers Norco Sight - Creaform Scanning
Behind the Numbers Norco Sight - Creaform Scanning
The C-Track unit keeps a watch on the handheld scanner and positions it in space.


Compared to the HandySCAN hardware previously used, it requires less reflective stick-on targets to locate the scanner in space. Instead, the MetraSCAN uses an additional C-Track unit to constantly watch the scanner and position it in space, with the spherical handheld scanner having multiple reflective targets all over it. The measuring volume of the system is about 16.6 cubic meters with a single fixed C-Track.

Reminiscent of the Martians in War of the Worlds, the C-Track can be moved around during a scan session, allowing you to get into all the nooks and crannies of a part and build up the 3D data you need. And by moving the C-Track around, you can scan larger objects than if the C-Track were to stay in one position. Multiple C-Tracks can also be linked together for these larger parts or to even create a metrology room, dedicated just to scanning.


Behind the Numbers Norco Sight - Creaform Scanning
Behind the Numbers Norco Sight - Creaform Scanning
The MetraSCAN 3D was the perfect tool for doing our repeated scans on the four bikes we took to the Creaform France office in Grenoble.


Once the initial setup was done for the bikes, with a small floor-mounted jig to fix the front wheel, it was a quick and easy process to setup the next bike and repeat the scan. With the setup and expertise of the Creaform team in France, we were able to accurately scan all four bikes in less than a day and safely return them to the shop without a single scratch.





Norco Sight Instant Centre
The Norco Sight uses a four-bar suspension system and so the instant center is a virtual point in space, depicted here by the engineering standard for showing an instant center - a cat.


The Norco Sight comes in two wheel sizes to cater for everyone’s preference, and we scanned the 29” version. Between the wheel sizes, reach, chainstay, effective seat angle, and seat tube length are the same. It’s only the head angle, bottom bracket height, fork offset, stack, and head tube length that change.

The Sight has 150mm rear travel, 160mm of fork travel, and touts much more progressive geometry than a lot of the other trail bikes out there today.

Norco Sight Analysis Details

Travel Rear: 149.6mm
Travel Front: 160mm
Wheel Size: 29"
Frame Size: M
CoG Height: 1,100mm
Chainring Size: 32T
Cassette Cog Sizes: 50T, 24T and 10T

Norco is one of only a few manufactures to evolve their chainstay length and seat tube angle as the sizes change. As the frame size grows, the chainstays get longer in 5mm increments and the virtual seat angle gets steeper. This is a standout point for Norco and the other manufacturers doing this. These changes work to keep the rider’s mass more balanced between the contact patches both when stood and seated.

The Sight uses a Horst pivot rocker link suspension layout, something tried and tested and also fairly common in its usage today, but with good reason. Compared to last week’s single-pivot suspension design, there's a disconnect between the mainframe and the rear axle with the Horst pivot. Something that can make some faux-bar suspensions systems look like the four-bar system like the Sight, but have different curves and options for the engineers to achieve their suspension goals.

With the inclusion of the Horst pivot it now means that the rear axle moves around a virtual point in space, called the instant center. As we move through the travel, this IC moves around in space, as opposed to being a fixed main pivot on the frame like the Commencal. This ability to move the IC around in a bigger window opens up more options to adjust and balance all the suspension characteristics.

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The instant centre moves around in space as the links that define it move with the rear wheel. The yellow dots represent the pivots of the bike and the red the IC.

Generally, the Horst pivot rocker link designs put all the suspension curves in a good starting range at the beginning of a bike's development. But that doesn’t guarantee that all bikes with this layout have good curves; it can still generate terrible curves and suspension traits. So, like with every suspension system, it still needs care and attention to have good suspension characteristics amidst balancing all the packaging, construction, aesthetics, and other concerns.

Another gold star for Norco is their Ride Aligned bike setup guide which is one of the best out there. The online guide uses your inputs of height, weight, and gender to suggest shock and fork setups covering pressures, tokens, and damping settings but also going as far as suggesting tire pressure and cockpit setup. There’s even adjustability in the setup guide to account for your riding skill, and it includes brilliant descriptions of each skill level, even adjusting for differences in setup for riders with a more forwards or rearward riding bias.





2020 Norco Sight Leverage Ratio

Leverage Ratio

The Sight has 18.43% progression with a starting leverage ratio of 3.22 and finishing at 2.62. Over the entire curve there’s an average leverage ratio of 2.85.

It uses a 185 x 52.5mm shock to generate its 150mm travel - just a note for when comparing back to the Commencal with its 130mm travel coming from a 50mm stroke.

The leverage ratio starts progressively until around the last third of travel where it begins to flatten out. Mike Kazimer reviewed the Sight 29 C1 back in February and needed to add an extra volume spacer to the shock to help tune for this end-stroke linearity. Initially starting with 30% sag, the bike was bottoming out a little too often for his liking. Upping to 25% helped with this but then brought some added harshness with the higher spring rate. In the end, he settled on that one extra volume spacer and 27% sag.

The Sight’s leverage ratio curve shape is remarkably similar to last week’s Meta TR 29, with the biggest differences coming from the values. But if we differentiate the leverage ratio curve there is a sign that the Sight actually has a subtle x^3 shape to it. This is something not seen from looking at just the leverage ratio curve and is a very subtle change to the Commencal’s x^2 shape, but differentiating the leverage ratio curve is a good way to zoom in and see the minute changes in it.

The ratios on the Sight are generally higher than on the Commencal, with those higher ratios putting more force into the shock and compressing it slower, which would usually call for higher spring rates and a slightly firmer damping tune.

30% shock stroke sag gives 32.44% rear-wheel travel. Not a hugely progressive leverage ratio so falls at about 2% of each other.

Mike commented that the bike felt more planted than poppy, something that can come from suspension setup, but in the case of the Sight comes from the slightly higher leverage ratios all round. Those higher ratios would allow the shock to move more readily into the travel when faced with rider inputs or impacts.

The Norco does have 3.8% more progression than the Commencal, but it’s likely these higher ratios combined with the end-stroke linearity that can give the feel of finding the bottom of the travel a bit more often. But that relatively smoothly changing leverage ratio curve again lends itself to a predictable feel and makes the bike react well to suspension adjustments.





2020 Norco Sight Anti-Squat

Anti-Squat

The Sight C1 29 comes with a 32-tooth chainring and SRAM Eagle gearing. Again, we took the 50, 24, and 10-tooth cogs as a good representation of the whole cassette.

Like a single pivot design, the Sight produces very close to straight lines for the anti-squat. For our analysis, all those curves start at the same 104% point. At 30% sag, there is 91% in the lightest climbing gear and would only result in a bit of squat from the load transfer when accelerating.

That percentage does drop as you go down the cassette, with 88% for the 24-tooth and 80% for the 10-tooth at sag.

There is a drop in the anti-squat curves as the bike goes through its travel, a bit more than the Commencal, down to just under 35% at its lowest point. But in the gears more associated with climbing there is less drop from start to finish, with the 24-tooth cog finishing at just above 55%.

The Sight’s brilliant seated position is also going to help the bike's climbing performance, not just due to being in a more comfortable position, but also balancing the rider’s mass between the contact patches more evenly than a bike with a really slack seat angle. Once pointed uphill that split between the contact patches becomes more rearward biased and the bike becomes more sensitive to the suspension squat from accelerating. The Sight’s seated position and the high anti-squat work together to statically and dynamically keep the load on the front wheel and make the bike’s long reach and slack head angle work really well when climbing.

The anti-squat may be a touch lower than the Commencal, and the leverage ratio is a touch higher, but the bike still provides a supportive feel when climbing in and out of the saddle.

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The red IC dot is carried over and creates the blue IC - rear axle line. Intersecting that with the chain line we get the instant centre of anti-squat, the green dot. The orange dot represents the 100% anti-squat mark.





2020 Norco Sight Pedal Kickback

Pedal Kickback

The Sight has 20mm more rear-wheel travel than the Meta TR 29 and so generates a bit more maximum pedal kickback in the 50-tooth gear, with 28.8 degrees in the big cog. But this then drops to 13.2 degrees in the 24T and 4.78 degrees in the 10T which is lower than the corresponding gears for the Commencal despite the extra travel.


Chain Stay Length vs Travel


Both the Commencal and the Norco have the same static chainstay length of 435mm and, surprisingly, they both finish with the same chainstay length of 455mm at the end of travel, despite the Norco having that extra 20mm.

If we take the same conditions as our previous test, riding along in the 24-tooth gear on the cassette and then rode off a 1m high drop that used 75% of our travel, how fast would we have to be going for the impact to not cause any pedal kickback?

In the case of the Norco, we’d have to be going 34.3km/h, or 21.4mph, for the pedal kickback to never be a problem. Only a fraction slower than the Commencal as the pedal kickback for the same parameters is fractionally less.

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Remember that pedal kickback is calculated with a fixed rear wheel and only looks at the influence on the crank. When we ride it can be a different matter. The blue line represents the bike at zero travel and the green shows how the cranks rotate backwards as the bike goes through its travel.





2020 Norco Sight Anti-Rise


Anti-Rise

That moving IC that we talked about can be used to generate really flat line anti-rise curves. In the case of the Sight it only varies by 1.4% from start to finish. That would mean that no matter where you are in the travel, the bike's response to rear braking would be the same. Your CoG would likely move as you went through travel, but this is true of all the other bike analyses.

The anti-rise hovers around 57% meaning that just over half the load transfer from rear braking would be counteracted. The remainder would go into having the suspension rise and could then work in conjunction with the dive in the fork to cause the load split between the contact patch to become more biased towards the front.

But there are a lot of bikes with anti-rise levels around the same as the Sight, which does strike a balance between combatting some of the load transfer from braking while allowing the suspension to move a little more freely while combatting the load transfer.

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It's only the red IC dot we need to calculate anti-rise. The orange one again represents the 100% anti-rise mark.





2020 Norco Sight Axle Path


Axle Path

There is a small amount of rearwards movement just before sag, 1.5mm. But from then on, it’s a forward’s trajectory for 16mm until bottom out. There is more overall movement when compared to the Commencal, but this is due to the extra travel that the Norco has. But the axle paths are again remarkably similar in their trajectory.

We once again come to the point that the Norco, while a bit more aggressively biased, is still a trail bike designed to go up, along, and down the hills. Unless the axle path is a clear driver in the development of a bike then it often comes after the other suspension characteristics and is more a result of achieving a good leverage ratio, anti-squat, and anti-rise curve.

If the axle path were to be a driving force in the bike's development, then several decisions have to fall in line with that quest for a truly rearward axle path. And contribute to many of the high pivot bike similarities in terms of suspension characteristics, layout, and packaging.


Swing Arm Length vs Travel


One interesting comparison point between the single-pivot Meta TR 29 and the four-bar Sight is the difference in swingarm length as we go through travel. For the Commencal, the swingarm length, or distance between the IC and rear axle, remains constant at 413mm. But for the Norco it starts with over double the swingarm length of 882mm and gradually shrinks to 553mm at the end of travel. This swingarm length effectively represents the radius of the curve at any point in the axle path, as it’s around the IC that the rear axle is rotating.





Assumptions in Analysis

For all the trail bikes we took size medium, and so we adjust our Center of Gravity (CoG) height to 1,100mm above the ground.

It’s good to remember that the analyses for anti-squat and anti-rise always assume a static CoG. In the real world, this is rarely the case, but needs to be done for analysis’ sake to allow it to be easily calculated and then compared to other designs and bikes. Once we have our analysis it’s then easy to add back in the real-world elements that are relevant to each of us and where we ride our bikes. For more chin-scratching about that, check out the Enginerding article on anti-squat.

There’s no industry standard for the fork in anti-squat and anti-rise analysis. We can either fix the fork travel to generate a single curve or we can adjust the fork travel as we go through the rear travel to create a window. For these analyses we leave the fork at fixed at full travel. Again, as long as these assumptions about AS and AR are known and understood, it’s easier to analyze and compare bikes.





Final Thoughts

bigquotesThe Norco Sight is overall a bigger bike from front to back and with more travel front and rear than last week’s Commencal Meta TR 29. It’s aimed a touch more towards descending and aggressive riding, but is still a well-balanced trail bike that can climb and comfortably descend, with brilliant geometry and predictable suspension, if a little easier to find the end of travel. These characteristics, both favorable and not, can be seen in the curves and values once we delve inside the suspension.

The Commencal might be a more evenly balanced for attacking both sides of the hills with its shorter travel and focus, but Norco chose a slightly more aggressive focus for the Sight that could see it configured to encroach into the enduro segment.

But as is commented in our review of the Sight, it climbs exceptionally with its mix of geometry and suspension, and can descend fast and predictably. And with Norco’s focus on achieving a good fit and balance for each rider size, it’s no surprise to see that it’s a really popular bike out on the trails.







152 Comments

  • 107 1
 Nerrrrrdddddssssss
  • 19 1
 This article shows that your 150mm bike is not a true 150mm. It's 149.6mm. Now everytime you had a bad ride. Remember you are 0.4mm short of rear travel. Good night.
  • 29 0
 The Sight and Optic are fast and really fun bikes.
  • 4 2
 I replaced the 160 Lyric with a 170 36 on my Sight. Very nice upgrade.
  • 1 0
 If there was one bike to do it all bike parks to XC rides would the Sight be it?
  • 3 1
 @Fullsend2-13: May I dare add the new Transition Sentinel to that list.
  • 2 1
 @Lando406: what about the Trek Remedy, YT Jeffsy and Santa Cruz Bronson?
  • 1 0
 @Fullsend2-13:

I haven’t ridden any of those, but the Sight has more progressive geo than all of them. I’ve been super stoked on my Sight’s ability to smash and play on everything and still climb really well.
  • 2 0
 @BrianColes: genuinely curious: if you need 170 mm why not choose the norco range?
  • 19 0
 52.5 mm shock for a 150mm of travel seems like a lot of leverage... Wonder what the pressures might be for 110 kg guy. My bike has 62.5 mm shock for 150mm of travel...
  • 3 0
 Id reckon you'd be getting close to maximum pressure allowed on the shock and get close to max damping.
I'm light at 75kg so I'm lucky and my sight works well for me but you could always pop your weight/details into the ride aligned app and see what comes out.
  • 11 0
 Looking around in forums/etc, this seems to be one of the big worries among owners and prospective buyers. According to the Ride Aligned setup app, the max weight listed is 240lbs, and thats recommends the max pressure for the shock.

The Sight was (is?) one of the bikes I have been really intersted in, but I'm ~200lbs geared up, and would be getting close to max pressure/max volume spacers.

I really wish they just went with a larger shock, or maybe did what Raaw did on their Madonna (two separate rocker links/shock sizes, depending on if you're over, or under 200lbs).
  • 6 11
flag feathers54 (May 22, 2020 at 2:49) (Below Threshold)
 im sorry but this really isn't an issue, I can name so many other bikes using this shock size with equal amounts of travel, you really think engineers would have chose the size if they thought the shock was going to blow up?
  • 2 0
 I’m 70kg and running 190psi for my sight@spudlord:
  • 6 1
 @feathers54: it might not be, but it's better to have lower LR. Coil helps to overcome the high sensitivity issues of air + high LRs
  • 5 13
flag feathers54 (May 22, 2020 at 4:10) (Below Threshold)
 @Lagr1980: im pretty sure the norco engineers r more qualified than you, there probably reason for what they've done?
  • 2 0
 I agree.
From my 1st gen sight 650b I ever thought that low ratio (i.e. relatively long shock stroke) with high ratio progression and light compression tune was desirable features on a full-sus...
  • 3 0
 @feathers54: there is a reason for sure, like standover height and short seat tube. Oh and sooo needed water bottle mounts lol...Is that a good enough reason? You decide, who am I to say.
  • 2 0
 Came here to inquire @dan-roberts about his thoughts on this subject. As much as I like Sight I feel it just wasn't engineered with this demographics in mind.
  • 12 3
 Do we really have this many body builders riding bikes or are we talking about obese people?
  • 2 0
 my enduro has 57 stroke for 170 travel...
  • 16 4
 @JohanG: It's easy to be in 200 lbs range, when you're not a midget
  • 4 3
 @JohanG so much for making riding more inclusive eh?
  • 2 0
 @ocnlogan: I am currently riding 2020 Sight Large- I weigh 255 pounds- Im riding max pressure, both hsc lsc at max setting and my sag is around 30%. I need to install more volume spacers ideally but it rides really well and doesn't feel sluggish at all.
  • 1 0
 @benderl85:

Which shock are you using?

Good info either way.

And for the people asking about obese people...

Once you get over about 6’ tall, it’s really not hard to get into the low-mid 200lb range, especially if the person has ever done any weight lifting in their past.

So I’d suspect that “most” of the people worried about max shock pressure on the sight are on L-XL frames.
  • 2 1
 Part of the reason I chose a Guerrilla Gravity - most of their products hover around 2.4 average leverage ratio. The Pistola and Shred Dogg are even lower - 2.36 averages.

Another great option for bigger guys is the new Foes Ridgeback. Only $2000 with shock for a Made in USA, low leverage, beefy 7.8lbs 140mm alloy frame.
  • 2 1
 @JohanG: It's pretty easy for us tall dudes to be heavy without being fat. I'm 6'3" and solid/muscular (not fat and not a big bodybuilder) and I'm 230lbs.
  • 2 2
 Just need a meg neg and you would be fine.
  • 10 0
 MegNeg would make things worse. It requires more air pressure to achieve proper sag, and for bigger guys that means exceeding maximum air pressure on the shock.
  • 1 4
 @JohanG: 6’4” and not built like a teen xc racer, but no body builder either. Just over 200 ready to ride. A bike like this Norco seems great on paper, until looking at this analysis and realizing that the pb reviewer had to add a spacer. That’s pretty much a deal breaker if you value mid stroke and bottom out support as much as I do.
  • 3 1
 The Super Deluxe builds will have plenty of room for increasing pressure. Due the different volume configurations of the Float X2 you would be running at or above max pressure (or looking at getting the shock retuned to the firmer compression tune).
  • 3 0
 @feathers54: a leverage ratio of 2.9 is pretty damn high. That requires a high compression stack, which in a heavy rider is going to require high pressure and shorten damper life pretty significantly.
  • 5 0
 The bike actually runs a 55mm stroke for 150mm of travel on all Fox builds. Only the Super Deluxe versions have 52.5mm, which have less than 150mm of travel. That was an oversight in the article. Also, I'm 106 kg and I don't have any issues with getting enough air in my shock. I also think Kazimer would have done better to remove all volume spacers and then add more air to 25% -28% sag instead of just adding spacers and sagging down. Makes the spring curve more closely resemble a coil shock, which works very well on this bike.
  • 4 0
 @DHhack: Mid stroke support is achieved by removing volume spacers and adding a small amount of air to the spring.
  • 1 0
 @grizzlyatom:

In the review Kazimer mentioned he tried 25% sag, 30% sag, and then settled on 27% sag and one additional volume spacer. So he wasn’t really “sagging down”.

Sounds like he was wanting more progression for larger hits, and a bit more supple off the top.
  • 1 0
 Depends how big is “big” I’m 6’4 215lbs and it offers way more tune ability for me at a 30psi increase with way more small bump and ramp up. Yea if you weigh 270 you are starting to look SOL no matter what change you make - get a different bike with more progressive leverage curve. @PHeller:
  • 1 0
 Check out the ride aligned app from Norco. The Float X2 would be maxed and the the Super Deluxe would have a bit of headroom. I'm about 106kg with kit and I am riding a Sight 29 in Large at 250-260 psi on the Super Deluxe, still playing around with the pressures.

www.norco.com/bike-setup-guide/bikes
  • 2 0
 130kg rider weight with gear, XL sight, running just under 320psi in the super deluxe shock. Rides great. Would ride better if I could drop 20kg, but I can ride the suspension stock. My last bike needed a custom tune to make the shock manageable.
  • 3 0
 @ReddyKilowatt: Im 6'1 180 and not a small guy, you have to be an absolute Unit at your height and weight. I assume you you just run through doors and say f*ck it to opening them? lol
  • 2 0
 @ocnlogan: All I'm pointing out is that he could have tried increasing rather than decreasing air volume in the shock. Sag is really a secondary indicator, while dynamic ride height and travel recovery is of primary concern. I've tried every reasonable combination of pressure/ volume spacer on my Sight, which I don't think Kazimer did. Too many riders simply add spacers until they don't bottom out. That's not really maximizing the adjustability of an air shock on a progressive frame. Progression on the latest bikes like the Sight is built into the linkage system, with the idea that the end user can use either a coil spring or a high-volume air shock. The spring doesn't need added ramp up at the end of stroke, and actually causes negative side-effects. When you do reduce volume, you get some really interesting rebound characteristics that can make it virtually impossible to tune the ride height and rebound damping. Simply put, this type of leverage curve needs more support in the middle 1/3 (that is where most of our riding takes place) of the travel, not the latter 1/3. Flattening the force curve rather than giving it excessive slope change is how you make the bike pedal/handle predictably, make the rebound damping most effective, and reduce bottoming out through successive hits.
  • 1 0
 @grizzlyatom: which then kills bottom out. That’s why this particular buyer wouldn’t work... for me and how/where I ride.
  • 2 1
 @DHhack: How do coil shocks work for so many WC racers? Bottom out resistance has more to do with rebound damping and mid-stroke support than end-of-stroke spring force. You won't get to the end of the stroke often if you have your dynamic ride height and spring rate set up correctly. Meg Negs on many Rockshox DH bikes do the same thing by increasing mid-stroke support. Mid-stroke is always king for suspension set up.

p.vitalmtb.com/temp_photos/10217/max_MEGNEG_30119.jpg
  • 2 0
 I had a 2012 Reign which is another 150mm bike. It bugs me with short stroke shocks that you have to really crank the shock pressure to compensate for the leverage ratio and lack of progression. I always ran the pressure way high which compromised small bump compliance but meant I didn't bottom it out all the time. Longer stroke shocks incorporated into these bikes give more control per click of adjustment and is what I hope my next bike will have.
  • 1 0
 @JohanG: I'm 290 pounds on a bike with gear. Not sure why you'd want to delineate whether that's body building or obesity. Norco has set the maximum rider weight for the Sight at 300 pounds so this bike by design should accommodate (and does) a wide range of riders.
  • 1 0
 @grizzlyatom: Interesting points. I'm 290 pounds with gear and running almost 320psi in the Super Deluxe shock. I don't bottom out, but I was thinking that may be because the pressure is so high. I was wondering about removing a spacer as well which seemed wrong but maybe...? Surprisingly with this suspension, the stock rebound tune is fine. Other bikes have needed custom tunes with the amount of pressure I need to run to keep sag reasonable.
  • 1 0
 @gnralized: You can still run light compression on this bike, just have to up the air. I'm 175 kitted up with 245lb air in a custom DPX with very little compression damping and it's light years better than the stock X2. On the other end, I know a pro on this bike with a custom tuned firm X2 who is happy and absolutely shreds it, but he's 200+ and might need that firm tune.
  • 1 0
 @grizzlyatom: Regarding the 55 Fox vs 52.5 RS thing - Fox's bumper on the X2 necessitates the longer stroke to get 150mm of non-bottom-out travel. Effectively, that 55 is a 52.5. A 55mm stroke in any other applicable shock (DPX, SD, Topaz) gets you 7mm more travel, as the stroke is actually 55mm to the bottom.
  • 2 0
 @PHeller: I had a bike with a 2.0 leverage rate...at 6'4 215ish I was running 140psi.
  • 1 0
 @grizzlyatom: sorry to say but they run a 55mm Fox due to the bottom out bumper on the 2020 Float X2 which doesn't allow full compression of the shock at bottom out; which is roughly 2-3mm less than the listed stroke. So the Sight does indeed achieve about 150mm travel at 52.5mm of stroke with both RS and Fox shocks.
  • 2 1
 @grizzlyatom: I’m not one of the top 50 guys on the planet so.... I’ve run coil and air, same bike and same trails. Both have the same problem on a bike with similar suspension traits as this Norco. To not bottom out 10-20 times on every 10 mile ride it needs to be oversprung and overdamped.
  • 1 0
 @grizzlyatom: heaps of hsc im guessing
  • 4 5
 @islander: So we should have a selection of bikes with compromised designs to accommodate a small portion of the market made up of unhealthy people? Downvote me if you're obese and in denial.
  • 4 5
 I don't even understand how this is a debate? It sounds like pinkbike is trying to be really nice about it and not call out Norco for making a bike that sucks. A 150mm travel all mountain bike that bottoms hard and often on less than extreme hits is a crap bike. You should be able to setup any bike at the recommended specs and be within a couple clicks and 5 psi of it being perfect. If not something is wrong.
  • 2 0
 @friendlyfoe: My sight hardly bottoms out at 30% sag. My previous bikes bottomed out much harsher and more frequently (SC Bro3,Bro2, Nomad3).
The leverage ratio does mean that the shock will need to generate higher damping forces at a lower oil flow rate for equivalent feel. Shock hysteresis effects will also be amplified. maybe @VorsprungSuspension can enlighten us.
  • 1 0
 @ocnlogan: I’m Riding Float X2
  • 3 1
 @JohanG: I'm 215lbs at 12%ish body fat. I don't want bikes that are going to roast the damper. Sorry.
  • 2 0
 @friendlyfoe: I know a few people on these bikes. The bottom outs are not any more often. Just go on the ride aligned app and select that you are a top rider on the ability level and run that setting. Problem solved and it feels absolutely fine and handles everything wonderfully.

P.S This same setting for the Optic is very good. f*ck the other settings... Add a Click of Low speed on the steeper trails.
  • 1 0
 @JohanG: speaking for myself, I’m always going to be a bigger guy (6’2”) but some heath issues over the last 2 years really limited my riding and I’m about 40lbs overweight. Even when I’m in pretty decent shape, I’m 190-200 lbs.
  • 16 0
 The only number I'm concerned with on my Norco sight is the UPS tracking number
  • 6 0
 I have Optic in my Sight for my next steed. Or vice versa. Damn that intriguing Norco Range.
  • 22 0
 You'll need some sniper optics with long range to get a good sight given how fluid those torrent storms can be.
  • 3 0
 @dirtyburger: Well done!
  • 2 1
 It seems like a great bike for a Raaw trail experience. You know, the type a Privateer would want.
  • 1 0
 In hindsight I should have opted for the optic@dirtyburger:
  • 7 0
 Wow. That’s all a bit too much.... and I’m an engineer!
  • 3 0
 @dan-roberts "It’s good to remember that the analyses for anti-squat and anti-rise always assume a static CoG. In the real world, this is rarely the case, but needs to be done for analysis’ sake to allow it to be easily calculated and then compared to other designs and bikes. "

Why assume a static COG? Why not assume instead some expected area where the COG will be. Then instead of presenting a single line in the kinematic graphs you present a line with upper and lower bounds lines based on the extremes of that COG area. Define the COG area as say a standard deviation of where the COG is located from some kind of telemetry data or barring that a reasonable assumption of what area the the COG will be in . You could even differentiate the expected COG range while climbing and while descending. I'd imagine the COG range while climbing would be higher, further forward and the std dev would be smaller relative to the descending position.

I'd guess that when comparing bikes in this fashion you'd see a lot of overlap of the areas between the upper and lower bound lines of each bikes kinematics which IMO is the more accurate analysis; i.e. ya, these 2 bikes have slightly different critical point placements but 90% of their kinematic areas overlap and thus the bikes feel really similar.
  • 1 0
 Probably a good idea but considering that what is presented here is already too much for 90% of the audience... ;-)
  • 2 1
 You got a supercomputer to model that kind of stuff?
  • 2 0
 I like the idea of calculating and displaying any analysis using the CoG position with more than a single line. Currently the industry is mostly using fixed CoGs and fork travels, which works OK as long as the assumptions are stated and you can understand the fundamentals of how it's calculated to then extrapolate to different CoG positions.
Right now I think @Happymtbfr is right, that we need to get the audiance all good with the current analysis before we go deeper. Maybe one day we could be showing anti-squat on a more complex graph that accounts for CoG position changes and fork travel changes. Maybe more importantly there's some work to be done on defining a clear industry standard for the CoG positions of different sized riders in different riding positions (stood climbing, seated climbing, stood braking for anti-rise). There's always work to be done and improvement to be had!
  • 1 0
 @dan-roberts: Imho, don't go too far.
AS values are limited, if you spend days calculating position you won't achieve a significantly better model. At that point, any damper setting, in the shock or in the fork, wil have much more effect on how the bike ride than the small errors on the antisquat you are calculating.
It's even worse with anti rise, forks spring rate is doing more for the rear suspension than any number from the frame (maybe with the exception of fork's angle)
It's ok as you do now, if it's not broken, don't fix it.
  • 2 0
 While I applaud the pedal kickback theme being given with the static/dynamic context (very rare to find this distinction being made on most articles) I think the reference gearing (24T) is a touch low, don't you think? I would say most of the times I end up using most of the travel I'm on higher gears, but that could be just me.

Also, since kickback is not an on/off thing, maybe a graph with y=pedal kickback angle and x=speed while all other assumed conditions stay the same could be interesting.

Anyway, great work @dan-roberts
  • 2 0
 Also how does the hub POE affect the kickback you actually feel. I am guessing a hub with a lower POE isn't going to be affected as much as a high engagement hub.
  • 4 0
 @fartymarty: A low POE hub can be affected just as much. Just likely won't happen as often.
  • 2 0
 So I ride 26t x 10-51, when climbing tech I’m in my largest cogs, do kickback got me is vert different from what folks are experiencing when climbing less steep terrain with low tech.

Kickback only matters when you’re powering up, over, through tech when climbing. Otherwise it’s on a downhill or flat where you can coast.
  • 1 0
 Completely understand. I took the 24T as we had already analysed it in our three different cassette gears and we could add in some more real world elements into the pedal kickback discussion. I've been working on that idea of a graph to show different gears and speeds for a fixed impact situation. I'm going to add in a few more written examples of the speed needed to avoid the pedal kickback in the coming articles. That way you can see how the speed really reduces as you go into the harder gears.
  • 1 0
 @dan-roberts: will you correct those speeds then? Im pretty sure the 34kmh kickback-avoid speed is actually wrong and should be something like 13kmh for the case treated here.
  • 2 0
 The tendency for the Sight to use travel non-judiciously almost led me to ditch it. Combine that with the X2 that would either be too harsh or blow through travel no matter what advice from Norco or tuners I took, I think I found the solution and I'm warming up to the bike quite a bit now. Geo and fit was always bang on, and now that the rear end is cooperating (DSD tuned DPX2), I'm excited as hell for summer...
  • 3 0
 Do like that bike. My 26" sight is a lesson in agility on anything except the really steep gnarly stuff. But thats probably just me.
  • 3 0
 Totally agree. My last bike was the 26 Sight, and it was an awesome do it all machine. The 29 version is high up on my next bike list.
  • 4 0
 Interested to know what the difference in travel will be with some bikes now going to different chain stay lengths per size
  • 3 0
 And the effect on the leverage ratio. The larger sizes will have higher leverage ratios and the heaviest riders too, making the shock work even harder. However, so long as you're not a chonk the Sight looks sorted.
  • 4 0
 @getonyourbike: am chonk. what do
  • 1 0
 @swenzowski: www.norco.com/bike-setup-guide/bikes probably stick to the super deluxe builds as their is more headroom with the max psi being 325 I think vs 250 with the Float X2. I'm 105kg around 260 psi on a Large 29 Sight with Super Deluxe.
  • 1 0
 @ppaulino: 300 w. Float X2
  • 1 0
 @bsdn06: Thanks for clarifying, wasn't sure! I think the super deluxe has more headroom if I'm not mistaken.
  • 2 0
 Generally it creates a longer lever and raises the leverage ratios. Like @getonyourbike explains. But, as I understand, Norco moves the entire suspension system backwards to create the longer chain stay lengths, rather than keeping all the pivot points in the same position and increasing the length of the chain stay. Given that they need a new main frame per size they can do all the necessary changes in the main frame. I know they've done this in the past, and could imagine they still do, but not 100% sure for their new bikes.
  • 1 0
 @dan-roberts: That is clever! Hopefully that's what they still do. Reduces the extra costs associated with size specific chainstay lengths too.
  • 1 0
 @getonyourbike: Yeah, it's a pretty smart way to do it with all things considered!
  • 1 0
 Curious to hear Mike Levy's comparison with what he's mentioned is his favorite bike of 2019 and "most capable trail bike I've ever ridden" the Pole Stamina 140? Most of the new big brand trail & endure bikes are following the geometry trends established by Pole, Nicholai and a few other boutique brands. As a long-low zealot, I think it's only getting better with this trend.
  • 1 0
 "The Norco does have 3.8% more progression than the Commencal, but it’s likely these higher ratios combined with the end-stroke linearity that can give the feel of finding the bottom of the travel a bit more often."

The Commencal is way flatter/linear-er at the end than the Norco...
  • 1 0
 How do those anti-rise formulas account for the location of the brake itself? On a single pivot, the rotational forces imparted to the frame from the wheel through the brake will tend to rotate the swingarm directly, which would tend to move the suspension into its travel. Where on a four-bar/horst-link that same rotational force doesn't to directly into the swingarm/chainstay, it goes into the seatstay, which is actually going to rotate the opposite way or not at all, depending on frame of reference, as the suspension compresses.

Pretty sure this single-pivot behavior is what people call "brake jack", where the suspension feels very firm under braking because the suspension is compressing (and stiffening a bit on any design that doesn't have a perfectly linear spring rate) despite the forward weight shift. It also causes a large reduction in traction when the weight shift is combined with the compression.

Brake-jack as a term isn't used as much any more, but was sometimes interchanged with anti-rise because statically it seems like compressing the suspension would counter much of the weight shift.
  • 1 0
 "There’s no industry standard for the fork in anti-squat and anti-rise analysis. We can either fix the fork travel to generate a single curve or we can adjust the fork travel as we go through the rear travel to create a window. For these analyses we leave the fork at fixed at full travel."

So, we are really comparing the seated-pedaling condition between bikes, because the CG is a good bit higher when the rider is standing off the saddle.

Wouldn't the real-world response for the rear AS curve under this condition be with the fork at sag? This would lower the AS % value by a little bit for each frame analyzed, but for a different amount for each bike depending on fork travel and HTA... So, to compare apples-to-apples between bikes you'd have to set fork sag at, say, 15% of fork stroke, and lower the CG by that 15% * sin (HTA).

What about AS after a certain point in the travel? It seems nonsensical: Have you ever bottomed the rear shock while pedaling? If I was about to hit something that big, I'd stand and prepare to take up the bump. So, maybe we can all ignore the AS values after, say, 70-80% of the travel? Where is that cut off?
  • 1 0
 There's been a bit of discussion about the current way anti-squat is calculated, and the assumptions needed. Hopefully the article we did on anti-squat made that clear and brought in some chin scratching for looking at that particular assumption. Currently I'm doing some analysis on the CoG position and fork travel influences on the anti-squat to best reflect the real world per bike while still keeping it understandable for the masses and easy to compare bikes. Maybe there's some work needed to define a standard in the industry for the CoG and fork travel, something consistent between manufacturers making it easier to compare bikes. It would also require manufacturers to actually publish their suspension curves, which very few do. Hence this suspension analysis series. Maybe in the not too distant future there will be a follow up article on anti-squat, taking what we've already done and going one step further to show these CoG and fork travel variations. I just have to make it not so geeky that people don't want to read it! And yes, I doubt there are many people pedalling at full bottom out. But there is more than one way to accelerate a mountain bike and we may as well look at the curve for the entire travel range to have a complete picture, even though towards bottom out their importance in the entire bike riding picture might be less important.
  • 1 0
 @dan-roberts
I could appreciate an article about linkage progression and vertical travel.
20% progression on a 120mm bike and 20% progression on a 200mm bike will not yield the same suspension "feel" despite sharing this number.
Is there a number that covers both progression and travel?
  • 1 0
 Total bottom out force, surely?
  • 1 0
 "In the case of the Norco, we’d have to be going 34.3km/h, or 21.4mph, for the pedal kickback to never be a problem"
I have been looking a lot without finding the basis for this calculation. I think I understand how this work: you feel the kickback as soon as your cassette spin faster than your hub body. My Problem is: how do you determine the spinning speed of the cassette? Don't you have to know the duration of the shock absorption to then calculate the rotational speed of the cassette?
I hope some of you guys can help figure this out, ( @Arierep @dan-roberts )
Thanks a lot in advance, cheers.
  • 1 0
 If you define a certain compression time for the bike to go through a range of travel, and you know the pedal kickback generated by that travel range, then you can calculate the cassette angular velocity from the gear ratio and equate it to a linear bike velocity.
  • 1 0
 @dan-roberts: Thanks, how do would you define this compression time? is arbitrary based on your experience? I can see it varying a lot depending on the settings of the shock/your weight etc...
  • 1 0
 @dan-roberts: actually i think its more ‘correct’ to look at peak shaft speed at start of impact and kickback rate in degrees per second instead of averaged over a compression event. Its also easier as you can simply take freefall speed as shaft speed directly and you dont need to make assumptions about how long compression takes.
  • 1 0
 These Behind the Numbers are excellent. One request, it would be nice to post the link to the first Intro Behind the Numbers piece in the opening of these articles. I'm probably the only one who hasn't memorized all these terms, so I end up searching for it.
  • 1 0
 There should be a link at the bottom of the article which takes you to the page with all the Behind the Numbers articles, including the intro one.
Or are there any particular terms you feel we need to explain more or better?
  • 1 0
 @dan-roberts: Thanks, I will remember to look for the link there when reading future BTN articles. In the past, I've needed to reference the cheat sheet Intro article well before I've made it to the end of the article. When I'm trying to understand the terms, the real world examples are most helpful, like the paragraph about how the steep seat tube angle and anti-squat work together. Anytime these terms that I'm vaguely familiar with are connected to riding experiences that I'm quite familiar with is most helpful for my non-engineer brain.

Besides just lusting after new bikes, what I enjoy from these articles is the mental focus of trying to understand it all. Thanks again.
  • 1 0
 @dan-roberts Re: the anti-squat numbers and CoG etc, how about checking this theoretical data with some ShockWiz experimental data? To see how much difference there is?
In the real world, you will load and unload suspension also because your body moves up and down while pedalling standing up. How this works together with anti-squat can be calculated of course but as an experimental physicist, I like to see experimental data too.
  • 1 0
 I need help! well, I wanna design and custom build a bike for myself. Do you have recomendation on software do design the linkage and kinematics and to design other pieces? Is there a library that could help?
  • 1 0
 @Mcbellamy: Whoa, thats a lot of information. Thank you! Also, is there a open source software?
  • 1 0
 Any idea what the leverage ratio does beyond 150mm? With 2.5mm more stroke a bit more travel could be achieved, but would the leverage ratio go regressive at some point?
  • 1 1
 A lot of bikes do this anyway
  • 3 0
 The X2 in mine is 55mm standard. Norco reckon it was needed to get the travel on Fox due to thicker bumper (so I am told by Norco aus). On a large and 80kg I am running 245psi. I think I like it better at 240psi though. Big hits I haven't felt harsh bottom and run stock volume spacers.
  • 2 0
 @PaulieAU: Yeah I heard the fox versions have 55 due to the bumper size (although I also don't think they do a 52.5, so that might also have something to do with it). There is clearance to run a rockshox with 55 mm stroke, particularly on the aluminium frames, which would give more travel than the rockshox 52.5 or fox 55. I just want to avoid getting weird suspension behaviour at the end of the travel.
  • 1 0
 @Bobadeebob: 2.5mm stroke at 2.62:1 gives you another 7mm of travel. From looking at that curve, I doubt anything wild will happen. The last part of the stroke is likely to be linear or very slightly progressive. So long as the frame doesn't eat itself, go for it.
  • 1 0
 I'm running a DPX with a 55mm stroke. I don't see a down side.
  • 4 0
 Loving my a1
  • 2 0
 Did you have the 2018/9 before it? If so, climb comparison please.
  • 1 0
 Same just got my 3rd ride in, thing is minty. Coming off a Capra 27.5, the Sight 29 A1 climbs better and is definitely more of a magic carpet vs the Capra.
  • 1 0
 What’s your rebound set at? I’ve got mine at 2clicks open@190psi@ppaulino:
  • 1 0
 @neilbarkman02: I played with 3-5 from closed, don’t have enough time to say what I prefer.
  • 2 0
 Just got an a1 and haven't taken it anywhere crazy but its so stable an planted, really surprised me!
  • 1 0
 It looks like the IC and axle are connected through the top of the chainring at pretty much every point in the travel. That’ll make for a really nice pedaling bike.
  • 1 0
 Not sure how many people are convinced by the numbers but everybody I know and their grandmother have bought one this year. I heard they are sold out.
  • 4 1
 I heard the bifocal rips
  • 1 0
 Where would the rider's COG be located for the purpose of these tests/analysis?
  • 1 0
 In the assumption section, they state a COG vertical position of 1100mm (from the ground).
  • 2 0
 do the canfield balance next!
  • 1 2
 Wondering how much of this applies to my Sight VLT. What an amazing bike. The 79 seat angle feels great, but doesn't make my Ripmo AF at 76 feel like a lawn chair after switching back to it.
  • 2 0
 Love my C2 29er sight. Beast.
  • 2 0
 Did you have the 2018/9 before it? If so, climb comparison please.
  • 6 0
 @rrolly: I had the 2019 Sight with 36 FIT4 K 150 mm fork. I also happen to have the 2018 Range with a 36 RC2 K 170mm.

The new Sight is a climbing machine and, other than speccing a shock on the L/ XL that does not have an adjustable LSC, they have nailed all the issues (minor) that I felt were weaknesses on the 2019 Sight.

Steeper seat tube brings centre of the saddle 63 mm further forward (@ 802mm saddle height), it has a slightly longer wheel base, longer rear triangle, slacker head angle but slightly off set by the shorter trail of the fork.

I have over forked it with a 170 mm Lyrik Ultimate RC2.

It climbs better than my 2020 Optic actually as I am even more centred (steeper seat tube and 5mm longer chain stay). It totally bombs descents with more ease than the 2018 Range (despite the similar suspension numbers, and despite the Vorsprung tuned Fox suspension on the 2018 Range) as one is naturally more centred. I cannot rave on enough about being even more centred than I felt on the 2019 Sight (which was my best ever bike until the 2020 Optic and Sight became available).

I am on a C9 Custom XL and I am 215 lbs riding weight. Ride Aligned suggests 235 psi for rear shock and 105 psi for fork. I ride fairly centred, clipped in and rarely sit back and drop my heels. Rockshox set up recommends 90 psi for the Lyrik.

After quite a bit of focused suspension set up laps with a ShockWiz and the stop watch, I am running 95 psi, 0 HSC, +3 LSC and +7 RB (from open/ faster) on the fork. Shockwiz suggests 90 psi and an extra token but the fork is about to get the C1 Seal head and foot nut upgrade which should increase initial sensitivity, ride slightly higher through lesser hits and ramp up like it has an extra token at the same pressure.

I am very happy with 255 psi with +6 RB on the rear SD Select +. Shockwiz suggests that I need to increase the LSC on the shock but I'll address that when I get Vorsprung to Tractive tune it.

Sorry short answer is that it is SO much better than the 2019 Sight it is hard to describe.
  • 1 0
 @andrewbikeguide: Nice details, thanks. What kind of terrain/where do you ride? When you say the 2020 climbs better, in what way?
  • 2 1
 I would love to see a VPP bike up next. Curious how the graphs will stack up.
  • 1 0
 That bike is cool and all, but that scanning tech is what really impresses me.
  • 2 0
 I don’t understand squat about this...
I just ride my Fkg bike hahahaha
  • 1 0
 Does this take account of compression of the FRONT shock working at the same time?
  • 2 0
 Keep em coming!
  • 1 1
 Whenever I see a "Behind the Numbers" article now I can't help but just think "Where's the Grim Donut!?"
  • 1 0
 If only they were in stock.
  • 1 0
 The animations on this are amazing. More of this, please.
  • 1 2
 Are you allowed to publish the dimensions from the scan? Or the raw scanned file?
  • 1 1
 I’d love to see one on the Maestro suspension for the Giant Reign 29!
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