Genuinely surprised they kept the twin chain transmission on the production bike.That is a lot of proprietary parts and complexity. I assumed they would just simplify...
Genuinely surprised they kept the twin chain transmission on the production bike.That is a lot of proprietary parts and complexity. I assumed they would just simplify it to a traditional idler set up. There must be some tangible benefits to justify it.
Besides better ground clearance, reduced drag, it also reduces chain growth of the bottom chain line, typical high pivot only reduces it on the upper chain line while derailleur has to compensate for even more chain growth at the bottom part. That through der. Clutch ads friction to the suspension. Weight and more bearings seems to be the only negative aspect here.
Genuinely surprised they kept the twin chain transmission on the production bike.That is a lot of proprietary parts and complexity. I assumed they would just simplify...
Genuinely surprised they kept the twin chain transmission on the production bike.That is a lot of proprietary parts and complexity. I assumed they would just simplify it to a traditional idler set up. There must be some tangible benefits to justify it.
Besides better ground clearance, reduced drag, it also reduces chain growth of the bottom chain line, typical high pivot only reduces it on the upper chain...
Besides better ground clearance, reduced drag, it also reduces chain growth of the bottom chain line, typical high pivot only reduces it on the upper chain line while derailleur has to compensate for even more chain growth at the bottom part. That through der. Clutch ads friction to the suspension. Weight and more bearings seems to be the only negative aspect here.
That new Pivot's long, upright seat tube and DW link suspension is making be wonder how it'd fare up a climbing trail with a nice wireless dropper post...
Glad to see in frame storage not being locked behind the carbon model like every other brand does (except Trek).
That is nice. Spec hasnt locked it away on the last stumpy evo. I think thats something they are probably sticking with. I still want to see an alloy enduro but its never gonna happen
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...
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 circle with the X in it), the mass effectively gets "left behind" during the acceleration, thus shifting the weight back over the rear wheel, causing the suspension to compress. This is extra annoying on a pedal bike, because the acceleration force is not constant, it ebbs and flows with every pedal stroke. If left unchecked, this bobbing causes a lot of energy loss.
OK, so onto anti-squat. In a linkage layout designed to combat squat (such as the Horst link depicted below), the force of the chain (which caused the bike to accelerate) is ALSO used to counteract the force caused by the rearward shift of the mass. This is achieved by placing the pivots of the rear triangle in such a way as to cause chain growth when the suspension compresses (i.e. the distance between the top of the chainring and the top of the cassette cog upon which the chain is resting becomes longer when the suspension compresses). When you then introduce a force vector along the chain, it causes the suspension to extend (the reverse action of chain growth). This is a mechanical movement that occurs in the linkage itself, it has nothing to do with a force being applied above the line from CoG to rear axle. Note that the main pivot point in this design (whether actual or virtual) is usually found somewhere on the same level or slightly above the rear axle. Anti-squat is measured as a number, 100 is basically when the force compressing the suspension (caused by the rearward movement of the mass) is equal to the force extending the suspension (generated in this case by the chain pulling on the linkages, causing the swingarm to move downwards).
And to conclude, the high-pivot with idler. Here, the anti-squat force is generated by the placement of the forward pivot at a point well above the rear axle. This means that any force applied to the rear axle in the forward direction below the main pivot will cause the connecting member (the swingarm) to want to rotate downwards, thus counteracting the squat-inducing force caused by the forward acceleration. This can be achieved without any chain growth if the idler is placed exactly inline with the main pivot. You can also play with the placement of the idler to add or subtract some "extra" anti-squat properties.
I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration.
You are right, a design with a pivot above the imaginary line between your CoG and the rear axle would be ridiculous and impractical, which is why every design relies on chain growth for antisquat.
Here are three pivot locations, the rear axle, and CoG. Both the low and the high solid red pivots are below that before mentioned imaginary line. You can see with the force arrows, if the rear wheel accelerates the bike+rider forward, the force vector between the forward acceleration and downward gravity acceleration drives forwards and downwards. The only way for the suspension to extend is for the pivot location to be above this line. This is the source of acceleration squat. The pink pivot location is the only one that will extend (but its in an impractical location).
Again, this is without a chain. The whole point of chaingrowth is to generate chain tension to overcome this. Again, if this were not so, where is the point where a high pivot is high enough to generate antiquat on its own without a chain?
Sorry for the delayed response, it was a while until I could watch the World Cup so I had to stay off Vital to avoid spoilers
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...
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 circle with the X in it), the mass effectively gets "left behind" during the acceleration, thus shifting the weight back over the rear wheel, causing the suspension to compress. This is extra annoying on a pedal bike, because the acceleration force is not constant, it ebbs and flows with every pedal stroke. If left unchecked, this bobbing causes a lot of energy loss.
OK, so onto anti-squat. In a linkage layout designed to combat squat (such as the Horst link depicted below), the force of the chain (which caused the bike to accelerate) is ALSO used to counteract the force caused by the rearward shift of the mass. This is achieved by placing the pivots of the rear triangle in such a way as to cause chain growth when the suspension compresses (i.e. the distance between the top of the chainring and the top of the cassette cog upon which the chain is resting becomes longer when the suspension compresses). When you then introduce a force vector along the chain, it causes the suspension to extend (the reverse action of chain growth). This is a mechanical movement that occurs in the linkage itself, it has nothing to do with a force being applied above the line from CoG to rear axle. Note that the main pivot point in this design (whether actual or virtual) is usually found somewhere on the same level or slightly above the rear axle. Anti-squat is measured as a number, 100 is basically when the force compressing the suspension (caused by the rearward movement of the mass) is equal to the force extending the suspension (generated in this case by the chain pulling on the linkages, causing the swingarm to move downwards).
And to conclude, the high-pivot with idler. Here, the anti-squat force is generated by the placement of the forward pivot at a point well above the rear axle. This means that any force applied to the rear axle in the forward direction below the main pivot will cause the connecting member (the swingarm) to want to rotate downwards, thus counteracting the squat-inducing force caused by the forward acceleration. This can be achieved without any chain growth if the idler is placed exactly inline with the main pivot. You can also play with the placement of the idler to add or subtract some "extra" anti-squat properties.
I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under...
I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration.
You are right, a design with a pivot above the imaginary line between your CoG and the rear axle would be ridiculous and impractical, which is why every design relies on chain growth for antisquat.
Here are three pivot locations, the rear axle, and CoG. Both the low and the high solid red pivots are below that before mentioned imaginary line. You can see with the force arrows, if the rear wheel accelerates the bike+rider forward, the force vector between the forward acceleration and downward gravity acceleration drives forwards and downwards. The only way for the suspension to extend is for the pivot location to be above this line. This is the source of acceleration squat. The pink pivot location is the only one that will extend (but its in an impractical location).
Again, this is without a chain. The whole point of chaingrowth is to generate chain tension to overcome this. Again, if this were not so, where is the point where a high pivot is high enough to generate antiquat on its own without a chain?
Sorry for the delayed response, it was a while until I could watch the World Cup so I had to stay off Vital to avoid spoilers
I'm struggling to work out who is less wrong here - but yes a bike absolutely has anti squat (and anti rise) without a chain on it. The bike is being pushed by the swingarm which can pivot, so the response of the rider weight means it will likely try to tip one way or the other. The chain is just a second torque being added to the equation which can offset that moment. I think this needs its own thread
In the webpage that shows the new stumpjumper alloy it also appears the "2025 demo", but I'm pretty sure that's the 2024 color scheme, does that means they are just going to try to push that model into 2025 and then release the updated one next year? After all the time that they've been testing the new one with ubb kinda sucks they went that road (if they did), same with the "new" enduro with just the udh upgrade and the thrilling new Matte black color 🥱
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...
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 circle with the X in it), the mass effectively gets "left behind" during the acceleration, thus shifting the weight back over the rear wheel, causing the suspension to compress. This is extra annoying on a pedal bike, because the acceleration force is not constant, it ebbs and flows with every pedal stroke. If left unchecked, this bobbing causes a lot of energy loss.
OK, so onto anti-squat. In a linkage layout designed to combat squat (such as the Horst link depicted below), the force of the chain (which caused the bike to accelerate) is ALSO used to counteract the force caused by the rearward shift of the mass. This is achieved by placing the pivots of the rear triangle in such a way as to cause chain growth when the suspension compresses (i.e. the distance between the top of the chainring and the top of the cassette cog upon which the chain is resting becomes longer when the suspension compresses). When you then introduce a force vector along the chain, it causes the suspension to extend (the reverse action of chain growth). This is a mechanical movement that occurs in the linkage itself, it has nothing to do with a force being applied above the line from CoG to rear axle. Note that the main pivot point in this design (whether actual or virtual) is usually found somewhere on the same level or slightly above the rear axle. Anti-squat is measured as a number, 100 is basically when the force compressing the suspension (caused by the rearward movement of the mass) is equal to the force extending the suspension (generated in this case by the chain pulling on the linkages, causing the swingarm to move downwards).
And to conclude, the high-pivot with idler. Here, the anti-squat force is generated by the placement of the forward pivot at a point well above the rear axle. This means that any force applied to the rear axle in the forward direction below the main pivot will cause the connecting member (the swingarm) to want to rotate downwards, thus counteracting the squat-inducing force caused by the forward acceleration. This can be achieved without any chain growth if the idler is placed exactly inline with the main pivot. You can also play with the placement of the idler to add or subtract some "extra" anti-squat properties.
I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under...
I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration.
You are right, a design with a pivot above the imaginary line between your CoG and the rear axle would be ridiculous and impractical, which is why every design relies on chain growth for antisquat.
Here are three pivot locations, the rear axle, and CoG. Both the low and the high solid red pivots are below that before mentioned imaginary line. You can see with the force arrows, if the rear wheel accelerates the bike+rider forward, the force vector between the forward acceleration and downward gravity acceleration drives forwards and downwards. The only way for the suspension to extend is for the pivot location to be above this line. This is the source of acceleration squat. The pink pivot location is the only one that will extend (but its in an impractical location).
Again, this is without a chain. The whole point of chaingrowth is to generate chain tension to overcome this. Again, if this were not so, where is the point where a high pivot is high enough to generate antiquat on its own without a chain?
Sorry for the delayed response, it was a while until I could watch the World Cup so I had to stay off Vital to avoid spoilers
"I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration."
No. At least not necessarily or not in all cases.
It's very well known that Red Bull has anti dive suspension geometry in the front (for braking) and anti squat geometry in the rear on their F1 car. At least they fine tuned it better than everyone else in the previous years, all the teams probably have it to some extent.
Antisquat (and antidive) geometry comes from cars, what bikes use is just an additional component due to chain drive that is very rarely used with cars. It's not something that was developed for bikes specifically. It comes from the motorcycle world. If anything, it's just so much more important than with other vehicles due to the nature of power delivery.
"I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats...
"I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration."
No. At least not necessarily or not in all cases.
It's very well known that Red Bull has anti dive suspension geometry in the front (for braking) and anti squat geometry in the rear on their F1 car. At least they fine tuned it better than everyone else in the previous years, all the teams probably have it to some extent.
Antisquat (and antidive) geometry comes from cars, what bikes use is just an additional component due to chain drive that is very rarely used with cars. It's not something that was developed for bikes specifically. It comes from the motorcycle world. If anything, it's just so much more important than with other vehicles due to the nature of power delivery.
Primoz, we are talking about bikes here 😁 so the question stands, does any bike out there has any antisquat with chain removed? If yes, how is the force generated?
There is a Test in the enduro magazine.
Didn't go through it, but the Pivot had the fastest lap for all 3 testers and they gave it best bike on test.
Besides better ground clearance, reduced drag, it also reduces chain growth of the bottom chain line, typical high pivot only reduces it on the upper chain line while derailleur has to compensate for even more chain growth at the bottom part. That through der. Clutch ads friction to the suspension. Weight and more bearings seems to be the only negative aspect here.
Or you could get a Ripmo AF for $2999 with GX eagle. (Or Deore for $3299)
Then you don’t have to support Giant.
From the other site. Mechanical Transmission spotted.
What are the odds are that they offer mechanical transmission above the SX level?
I could maybe see them offering it at GX and having that be the crossover point.
I’m seeing GX-level builds with unspecified derailleurs in my embargoed crystal ball…
I haven’t seen anything about it in the orb, but I’m really hoping the X0 tier survives in a cable actuated format as well.
@wellbastardfast it does look like it is possible afterall
Blurry pics, but it looks like plastic garbage.
This.
All super worthwhile for a racing prototype, I just didn't think it would see production.
It is super cool.
True, but at least it's possible the plastic's due to prototyping...
Wonder how high up in their range there's going to be a mechanical option
I can't see it going above GX.
That new Pivot's long, upright seat tube and DW link suspension is making be wonder how it'd fare up a climbing trail with a nice wireless dropper post...
The lugged frame looked better.
Glad to see in frame storage not being locked behind the carbon model like every other brand does (except Trek).
That is nice. Spec hasnt locked it away on the last stumpy evo. I think thats something they are probably sticking with. I still want to see an alloy enduro but its never gonna happen
They will be very cautious not to threaten their electronic high end stuff.
Also the market for mechanical high-end could be small, and already some good competition in there
It's not made production yet.
I like to support Giant, why not? 🤷♂️
This?
You can afford to spec (shitty) Fox when you haven't spent a dime on R+D since 2011.
What bike?
But we’re not supporting Giant 😉 Also forgot Marin has storage on an alloy frame too.
I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration.
You are right, a design with a pivot above the imaginary line between your CoG and the rear axle would be ridiculous and impractical, which is why every design relies on chain growth for antisquat.
Here are three pivot locations, the rear axle, and CoG. Both the low and the high solid red pivots are below that before mentioned imaginary line. You can see with the force arrows, if the rear wheel accelerates the bike+rider forward, the force vector between the forward acceleration and downward gravity acceleration drives forwards and downwards. The only way for the suspension to extend is for the pivot location to be above this line. This is the source of acceleration squat. The pink pivot location is the only one that will extend (but its in an impractical location).
Again, this is without a chain. The whole point of chaingrowth is to generate chain tension to overcome this. Again, if this were not so, where is the point where a high pivot is high enough to generate antiquat on its own without a chain?
Sorry for the delayed response, it was a while until I could watch the World Cup so I had to stay off Vital to avoid spoilers
I'm struggling to work out who is less wrong here - but yes a bike absolutely has anti squat (and anti rise) without a chain on it. The bike is being pushed by the swingarm which can pivot, so the response of the rider weight means it will likely try to tip one way or the other. The chain is just a second torque being added to the equation which can offset that moment. I think this needs its own thread
Until the front fell off.
In the webpage that shows the new stumpjumper alloy it also appears the "2025 demo", but I'm pretty sure that's the 2024 color scheme, does that means they are just going to try to push that model into 2025 and then release the updated one next year? After all the time that they've been testing the new one with ubb kinda sucks they went that road (if they did), same with the "new" enduro with just the udh upgrade and the thrilling new Matte black color 🥱
"I'm sorry, you are simply incorrect in your analysis. Virtually all antisquat comes from chain tension, and without it every vehicle with pivot-based suspension squats under acceleration."
No. At least not necessarily or not in all cases.
It's very well known that Red Bull has anti dive suspension geometry in the front (for braking) and anti squat geometry in the rear on their F1 car. At least they fine tuned it better than everyone else in the previous years, all the teams probably have it to some extent.
https://suspensionsecrets.co.uk/anti-squat-dive-and-lift-geometry/
Antisquat (and antidive) geometry comes from cars, what bikes use is just an additional component due to chain drive that is very rarely used with cars. It's not something that was developed for bikes specifically. It comes from the motorcycle world. If anything, it's just so much more important than with other vehicles due to the nature of power delivery.
Primoz, we are talking about bikes here 😁 so the question stands, does any bike out there has any antisquat with chain removed? If yes, how is the force generated?