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2020 MTB Tech Rumors and Innovation

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5/5/2020 5:34 AM

Primoz wrote:

What I think is they don't do much because the chain is relatively slack (tensioned only by the derailleur cage in fact). That means any articulation and rotation will take up relatively small amounts of energy (or power) since the friction losses will be reduced.

That same fact is why I think idler pulleys also sometimes maybe feel draggy (I haven't had the chance to ride a bike with one yet, so going off Internet banter here) and most certainly are noisy - idler pulleys are invariably small.

Story time. With the classical drivetrain layout your chain is taught, how much depending on the power output, from the last tooth in contact with the cassette to the first tooth in contact with the chainring. As soon as you get to the second tooth (on either side), the amount of force applied to the chain lowers because of elasticity of both the sprocket and the chain (and a bit due to geometry of the forces acting on the system and all). Ballparking here, but I'd say somewhere around 5 to 10 teeth in all your tension in the chain is gone (depending on the sprocket size of course, it's probably 2 teeth for a 10T sprocket and up to 10 on a 50T sprocket). A similar story happens with threads in bolts and nuts, almost 90 % of the load is carried by the first three threads, then it all tapers off.

How does that all connect together? Your chain losses come from the rotation of the links. The bigger the chainring/sprocket, the less each link rotates when it wraps around the sprocket. Plus in a classical drivetrain the chain only unwraps once (coming off the cassette) and wraps (wrapping around the front chainring) once when it is taught, therefore producing any meaningful loss in the system from friction. All other movement of the chain is in a relatively slack condition and has much lower losses.

The idler? It adds a whole another unwrapping and rewrapping of the chain in the powered state and I think the chain is taught all around it because it's essentially pulled from both sides. Add the fact that idlers are small, increasing the angle of rotation in the links and you get more losses, more noise from all the tension, etc.

I hope I made it clear enough, if anything is not clear I can easily try to explain it again smile

*I am not an engineer and have no actual knowledge of these sorts of things*

This is an interesting point brought up with idler pulleys - they definitely do not follow 'efficiency guidelines' like track cyclists do, where they make a gear ratio with the largest possible chainring + sprocket to minimize chain articulation.
That being said, it is the articulation of the chain that seems to matter more than the size of the ring. Would an idler like the prototype Norco Aurum (where it sat only a bit above the chainring) be inherently more efficient than the Aurum HSP since the chain articulates less, no matter the pulley size?
All that being said, why are companies using such small pulley wheels for idler bikes? I would like to think it's not a weight thing since an idler is going to add weight anyway - what's the difference in adding 200 vs 210 grams? Though that is enough to dissuade some. Is it an availability thing? Maybe no one is making 50 tooth pie plates for idler bikes for some reason? Is this the Illuminati?!?!?
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5/5/2020 7:29 AM

Status is definitely interesting, I’m sure it will sell well but the sub $2000 references above are way off. In those photos, it has the same exact spec as the sj evo comp which is $3700.

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5/5/2020 7:41 AM

TheSuspensionLabNZ wrote:

The drag complaint is funny because I would bet that at least 50% of people with derailleur bikes are experiencing more power loss dues to worn parts, cross-chaining, poor lube and poor cleaning practises than they would from a gearbox!

Primoz wrote:

I wrote this in the morning but it somehow got lost... Anywho.

The way I was taught in college is that each bearing has an efficiency of 0,99 and each gear pair also has an efficiency of 0,99 (in the case of steel gears, which we have with Pinion). It's generalisation, but still. In a Pinion gearbox, the driven branch will have at least 6 bearings and 2 gear pairs doing the transmissioning of power from the pedals to the chain. Take away two bearings to substitute the bottom bracket of a classic derailleur transmission and you have 4 bearings and two gear pairs, giving you an efficiency of 0,99^6 = 94 %. So by design, the Pinion will lose _at least_ 6 % compared to the classical transmission because of the components a cassette-derailleur transmission doesn't have. You win some of that back with a straighter chain in the case of the Pinion, while a dirty and worn drivetrain is neither here nor there, it's more or less equal for both sides (okay, you could argue this issue is exacerbated with a worn chain, buy maybe the bendiness is actually improved with wear).

The kicker? With a P1.12 gearbox besides the powered branch I mentioned you also spin additional 5 gear pairs (it's a 3x4 layout, a two stage gearbox) where at least one of those two needs to be bearinged. They are not powered, so power losses will be smaller than on the driven branch, but the losses are still present.

Now, I do believe Pinion is relatively okay, I wouldn't be surprised if a Pinion is less lossy on it's own than say a DH casing, half empty aggro tread tyre is.

An additional remark, gearboxes being heavy I think came out of Rohloff internal gear hubs, where planetary drives are used. These use at least 3 planet gears which means, by definition, at least 6 bearing pair contacts (with each planet interfacing with the sun and the ring gear). And 3 bearings. The more planets you have, the more losses you have. So a Rohloff will be on the back foot from the start. And it could be the reason gearboxes are though to be draggy.

TheSuspensionLabNZ wrote:

Yeah you're pretty spot on at 94% efficiency, thats consistent with the average measured power losses I've seen recorded for the pinion. If you compare it to the data from zerofrictioncycling.com, who have the best drivetrain data I have seen -

Factor in the vast differences in contamination resistance or absorption, differing levels of
chain and drive train maintenance, and real world differences between chains can easily be
10w+. There are cyclists using –unbeknownst to them – a poor performing lubricant and
with average attention to maintenance who will literally be running a 15 to 20w loss chain at
250w load, vs cycling buddies on a top performing lubricant with good maintenance sitting
anywhere between around 5 to 8w loss.


You can get bang on equal loss in power between the 2 (250w x .94 - 5w (for a good lube) = 230, 250w-20w (for a poor drivetrain) = 230!)

Taken from here - https://zerofrictioncycling.com.au/wp-content/uploads/2019/05/Key-Learnings-from-Lubricant-Testing-Round-1.pdf

And I agree, I think most peoples perception of Gearboxes comes from Rohloff hubs!

Strangely enough, Rohloff hubs are MORE efficient than Pinion, and even more efficient than a 1x11 drivetrain when you're in the lowest gear and have the most severe offset chainline. Of course a 2x11 is the most efficient of them all since you can maintain a straighter chainline.

https://www.cyclingabout.com/speed-difference-testing-gearbox-systems/

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5/5/2020 11:25 AM

Primoz wrote:

What I think is they don't do much because the chain is relatively slack (tensioned only by the derailleur cage in fact). That means any articulation and rotation will take up relatively small amounts of energy (or power) since the friction losses will be reduced.

That same fact is why I think idler pulleys also sometimes maybe feel draggy (I haven't had the chance to ride a bike with one yet, so going off Internet banter here) and most certainly are noisy - idler pulleys are invariably small.

Story time. With the classical drivetrain layout your chain is taught, how much depending on the power output, from the last tooth in contact with the cassette to the first tooth in contact with the chainring. As soon as you get to the second tooth (on either side), the amount of force applied to the chain lowers because of elasticity of both the sprocket and the chain (and a bit due to geometry of the forces acting on the system and all). Ballparking here, but I'd say somewhere around 5 to 10 teeth in all your tension in the chain is gone (depending on the sprocket size of course, it's probably 2 teeth for a 10T sprocket and up to 10 on a 50T sprocket). A similar story happens with threads in bolts and nuts, almost 90 % of the load is carried by the first three threads, then it all tapers off.

How does that all connect together? Your chain losses come from the rotation of the links. The bigger the chainring/sprocket, the less each link rotates when it wraps around the sprocket. Plus in a classical drivetrain the chain only unwraps once (coming off the cassette) and wraps (wrapping around the front chainring) once when it is taught, therefore producing any meaningful loss in the system from friction. All other movement of the chain is in a relatively slack condition and has much lower losses.

The idler? It adds a whole another unwrapping and rewrapping of the chain in the powered state and I think the chain is taught all around it because it's essentially pulled from both sides. Add the fact that idlers are small, increasing the angle of rotation in the links and you get more losses, more noise from all the tension, etc.

I hope I made it clear enough, if anything is not clear I can easily try to explain it again smile

Masjo wrote: *I am not an engineer and have no actual knowledge of these sorts of things*

This is an interesting point brought up with idler pulleys - they definitely do not follow 'efficiency guidelines' like track cyclists do, where they make a gear ratio with the largest possible chainring + sprocket to minimize chain articulation.
That being said, it is the articulation of the chain that seems to matter more than the size of the ring. Would an idler like the prototype Norco Aurum (where it sat only a bit above the chainring) be inherently more efficient than the Aurum HSP since the chain articulates less, no matter the pulley size?
All that being said, why are companies using such small pulley wheels for idler bikes? I would like to think it's not a weight thing since an idler is going to add weight anyway - what's the difference in adding 200 vs 210 grams? Though that is enough to dissuade some. Is it an availability thing? Maybe no one is making 50 tooth pie plates for idler bikes for some reason? Is this the Illuminati?!?!?

I think it's a packaging issue. A small idler is very compact and relatively easy to implement.

As for the two Norcos, I think you're aiming at the wrapping angle, not articulation. The wrapping angle doesn't matter, the link will rotate the same once it's starting to wrap around a chainring regardless of how it wraps. It's only where it unwraps that the wrapping angle defines. The link rotation is the same for a given number of teeth regardless of the wrapping angle.

The number of teeth of a chainring define the radius around which the chain wraps and that defines how much each link has to rotate in regards to the neighbour. This is also connected to the polygon effect that is exhibited on small chainrings (and is supposedly the reason Sram went 10-42 for their 1x11 drivetrain as opposed to a 9T smallest sprocket they were testing in development - supposedly the variation in speed could be felt through the pedals?). The less teeth you have, the tighter the angle between two sides of a polygon and the more the links have to rotate.

This is all thinking out loud without any numbers, calculations or tests to back it up, but to me it's sound logic. I could be wrong.

As for the idlers, it has to be a packaging/practicality issue. But I would try out a mule with a layshaft. You are limited to how low you can position the main pivot then, since you can bring a small idler much closer than a layshaft with a 32T sprocket (on the output side), but with clever packaging (overlapping primary and secondary sprockets and using a pair of 22T sprockets for the first stage) it might be possible to get relatively close. It would be heavier and more complex to package, so there's a question if the packaging and weight headaches are worth the marginal gains in efficiency and noise, but you can't know unless you try smile

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5/5/2020 1:40 PM

Primoz wrote:

I wrote this in the morning but it somehow got lost... Anywho.

The way I was taught in college is that each bearing has an efficiency of 0,99 and each gear pair also has an efficiency of 0,99 (in the case of steel gears, which we have with Pinion). It's generalisation, but still. In a Pinion gearbox, the driven branch will have at least 6 bearings and 2 gear pairs doing the transmissioning of power from the pedals to the chain. Take away two bearings to substitute the bottom bracket of a classic derailleur transmission and you have 4 bearings and two gear pairs, giving you an efficiency of 0,99^6 = 94 %. So by design, the Pinion will lose _at least_ 6 % compared to the classical transmission because of the components a cassette-derailleur transmission doesn't have. You win some of that back with a straighter chain in the case of the Pinion, while a dirty and worn drivetrain is neither here nor there, it's more or less equal for both sides (okay, you could argue this issue is exacerbated with a worn chain, buy maybe the bendiness is actually improved with wear).

The kicker? With a P1.12 gearbox besides the powered branch I mentioned you also spin additional 5 gear pairs (it's a 3x4 layout, a two stage gearbox) where at least one of those two needs to be bearinged. They are not powered, so power losses will be smaller than on the driven branch, but the losses are still present.

Now, I do believe Pinion is relatively okay, I wouldn't be surprised if a Pinion is less lossy on it's own than say a DH casing, half empty aggro tread tyre is.

An additional remark, gearboxes being heavy I think came out of Rohloff internal gear hubs, where planetary drives are used. These use at least 3 planet gears which means, by definition, at least 6 bearing pair contacts (with each planet interfacing with the sun and the ring gear). And 3 bearings. The more planets you have, the more losses you have. So a Rohloff will be on the back foot from the start. And it could be the reason gearboxes are though to be draggy.

TheSuspensionLabNZ wrote:

Yeah you're pretty spot on at 94% efficiency, thats consistent with the average measured power losses I've seen recorded for the pinion. If you compare it to the data from zerofrictioncycling.com, who have the best drivetrain data I have seen -

Factor in the vast differences in contamination resistance or absorption, differing levels of
chain and drive train maintenance, and real world differences between chains can easily be
10w+. There are cyclists using –unbeknownst to them – a poor performing lubricant and
with average attention to maintenance who will literally be running a 15 to 20w loss chain at
250w load, vs cycling buddies on a top performing lubricant with good maintenance sitting
anywhere between around 5 to 8w loss.


You can get bang on equal loss in power between the 2 (250w x .94 - 5w (for a good lube) = 230, 250w-20w (for a poor drivetrain) = 230!)

Taken from here - https://zerofrictioncycling.com.au/wp-content/uploads/2019/05/Key-Learnings-from-Lubricant-Testing-Round-1.pdf

And I agree, I think most peoples perception of Gearboxes comes from Rohloff hubs!

hamncheez2003 wrote:

Strangely enough, Rohloff hubs are MORE efficient than Pinion, and even more efficient than a 1x11 drivetrain when you're in the lowest gear and have the most severe offset chainline. Of course a 2x11 is the most efficient of them all since you can maintain a straighter chainline.

https://www.cyclingabout.com/speed-difference-testing-gearbox-systems/

Well this is completely unexpected. I would really like some more details about the test (not much were given) and a possible explanation for this.

There is a possible mistake there though, it's said a faster moving chain (Pinion) is less efficient than the slower mowing chain (Rohloff). I'd say it should be the other way around, a faster moving chain transfers the same power with less chain tension, meaning less force in the chain, which I think should be beneficial for efficiency. Again, I could be wrong though.

I'd really like an explanation for those numbers though.

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5/5/2020 3:03 PM

watchcwgo wrote:

Status is definitely interesting, I’m sure it will sell well but the sub $2000 references above are way off. In those photos, it has the same exact spec as the sj evo comp which is $3700.

As the first poster to make a “Sub-2000” reference...

I was not stating the build as pictured would be sub-2000, but rather that I think another good geometry full suspension bike that has builds starting under 2000 (in the spirit of the original Status) would be a good product position for a big company like Specialized to target. I also expanded and stated that a lower overhead sales model might help that position.

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5/5/2020 4:34 PM

watchcwgo wrote:

Status is definitely interesting, I’m sure it will sell well but the sub $2000 references above are way off. In those photos, it has the same exact spec as the sj evo comp which is $3700.

PlunderPath667 wrote:

As the first poster to make a “Sub-2000” reference...

I was not stating the build as pictured would be sub-2000, but rather that I think another good geometry full suspension bike that has builds starting under 2000 (in the spirit of the original Status) would be a good product position for a big company like Specialized to target. I also expanded and stated that a lower overhead sales model might help that position.

I feel like this is where Giant tried to go with the Stance, except they missed out on the whole 'good geometry' thing

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5/7/2020 7:46 PM

Unimpressed.

Pretty much another DHR knock-off except sharper ramp on some the knobs.

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5/8/2020 10:30 AM

Just a random thought but do you think Some companies Have put new product releases on hold until we return to some kind of normalcy?

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5/8/2020 1:27 PM

Now that’s a gr8 question

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5/8/2020 1:51 PM

therock911 wrote:

Just a random thought but do you think Some companies Have put new product releases on hold until we return to some kind of normalcy?

big question for sure. it would seem that any 2020/2021 product to be launched this spring/summer is already done. maybe there are fulfillment issues with production if product is coming out of china? i really wonder how scheduled 2022/2023 product be handled? the product managers always hint that they're working way down the line w/ product (b/c they have to plan that far ahead). will all that be pushed backed or nuked completely?

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5/8/2020 2:54 PM

therock911 wrote:

Just a random thought but do you think Some companies Have put new product releases on hold until we return to some kind of normalcy?

sspomer wrote:

big question for sure. it would seem that any 2020/2021 product to be launched this spring/summer is already done. maybe there are fulfillment issues with production if product is coming out of china? i really wonder how scheduled 2022/2023 product be handled? the product managers always hint that they're working way down the line w/ product (b/c they have to plan that far ahead). will all that be pushed backed or nuked completely?

I'm sure we'll start seeing some stuff start popping up in august/sept as usually happens as a ramp up for the next season. Kind of expecting RS to start showing off the Zeb around then for the last two EWS races or maybe for Trophy of nations. I'm sure their original plan was crankworks air DH and the EWS race in whistler.

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5/8/2020 2:58 PM

therock911 wrote:

Just a random thought but do you think Some companies Have put new product releases on hold until we return to some kind of normalcy?

sspomer wrote:

big question for sure. it would seem that any 2020/2021 product to be launched this spring/summer is already done. maybe there are fulfillment issues with production if product is coming out of china? i really wonder how scheduled 2022/2023 product be handled? the product managers always hint that they're working way down the line w/ product (b/c they have to plan that far ahead). will all that be pushed backed or nuked completely?

I don't think delays would be coming from China, I've read a few reports that they are back to normal production. Anyone else know if this is true or false?

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5/8/2020 3:40 PM

Mtbforlife4 wrote:

I don't think delays would be coming from China, I've read a few reports that they are back to normal production. Anyone else know if this is true or false?

China is pretty much back into full production, I have friends over there that work for factories producing different things, but its the shipping thats an issue with the bag log of stuff and certain counties not excepting things from certain countries and then when the country does get it they hold onto it for a week or so to quarantine it.

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5/8/2020 7:12 PM

peecee wrote:

China is pretty much back into full production, I have friends over there that work for factories producing different things, but its the shipping thats an issue with the bag log of stuff and certain counties not excepting things from certain countries and then when the country does get it they hold onto it for a week or so to quarantine it.

I'm pretty sure that I had the virus back in January from some CNC parts express shipped from China. I wish we had had time to quarantine parts for a week. Antibody test tomorrow or Monday. We'll see.

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5/9/2020 11:36 AM

Hope your OK brother, you gotta watch out for the bubble wrap its full of Wuhan air!

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5/9/2020 8:12 PM

Pedal4life wrote:

Hope your OK brother, you gotta watch out for the bubble wrap its full of Wuhan air!

Photo
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5/12/2020 2:43 AM

Looks like I was right. There’s a guy in NZ who has them Photo

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5/12/2020 4:23 AM

Jrp wrote:

Looks like I was right. There’s a guy in NZ who has them Photo

I know the shock will prob work very well but DVO should employ a new graphic designer as this looks horrible, looks like it belongs on a alien spacecraft from the 90’s!

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5/12/2020 4:42 AM

Jrp wrote:

Looks like I was right. There’s a guy in NZ who has them Photo

peecee wrote:

I know the shock will prob work very well but DVO should employ a new graphic designer as this looks horrible, looks like it belongs on a alien spacecraft from the 90’s!

I'd be terrified to use it incase people thought I drank monster.

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5/12/2020 5:50 AM

Jrp wrote:

Looks like I was right. There’s a guy in NZ who has them Photo

peecee wrote:

I know the shock will prob work very well but DVO should employ a new graphic designer as this looks horrible, looks like it belongs on a alien spacecraft from the 90’s!

Mike_Scubadog wrote:

I'd be terrified to use it incase people thought I drank monster.

I see what they are trying to do here. First we had Öhlins who have their signature yellow spring. Then Fox with their signature orange spring. Then Rockshox came along with their signature red spring. Formula have shown their purple spring and now DVO with their green spring. It's like purple anodizing goes with everything (BECAUSE), Magura HS-33 yellow goes with everything, blue RS SID goes with everything, Red Rockshox Lyrik/BoXXer go with everything etc...

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5/12/2020 6:29 AM

rumor has it that DVO shock is made in Wakanda and the spring is made from Vibranium

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5/12/2020 8:14 AM

Jrp wrote:

Looks like I was right. There’s a guy in NZ who has them Photo

Looks like a progressive spring! Yes!!!

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5/12/2020 3:24 PM
Edited Date/Time: 5/12/2020 3:29 PM

According to an employee who posts regularly on another forum -

Quote: "We are in testing stages with this guys and wont be available for a while 5 maybe 6 months and this green might not be an opton sorry".

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5/12/2020 3:33 PM
Edited Date/Time: 5/12/2020 3:34 PM

Im just looking at buying a new bike and thought i'd try the Canyon website and it looks as if this is a new old sender, I know its not the new sender with different shock position but I've not seen this sender colour pop up anywhere before and it has new on it.
Correct me if Im wrong thou
Photo

Photo

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5/12/2020 5:01 PM

new sender in July smile

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5/12/2020 5:48 PM

baronKanon wrote:

I see what they are trying to do here. First we had Öhlins who have their signature yellow spring. Then Fox with their signature orange spring. Then Rockshox came along with their signature red spring. Formula have shown their purple spring and now DVO with their green spring. It's like purple anodizing goes with everything (BECAUSE), Magura HS-33 yellow goes with everything, blue RS SID goes with everything, Red Rockshox Lyrik/BoXXer go with everything etc...

RS had a red spring in the late 90's

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5/12/2020 6:41 PM

Mike_Scubadog wrote:

I'd be terrified to use it incase people thought I drank monster.

baronKanon wrote:

I see what they are trying to do here. First we had Öhlins who have their signature yellow spring. Then Fox with their signature orange spring. Then Rockshox came along with their signature red spring. Formula have shown their purple spring and now DVO with their green spring. It's like purple anodizing goes with everything (BECAUSE), Magura HS-33 yellow goes with everything, blue RS SID goes with everything, Red Rockshox Lyrik/BoXXer go with everything etc...

peecee wrote:

RS had a red spring in the late 90's

Anyone know how easy it is to strip the paint off all of these springs?

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5/12/2020 7:25 PM
Edited Date/Time: 5/12/2020 7:26 PM

baronKanon wrote:

I see what they are trying to do here. First we had Öhlins who have their signature yellow spring. Then Fox with their signature orange spring. Then Rockshox came along with their signature red spring. Formula have shown their purple spring and now DVO with their green spring. It's like purple anodizing goes with everything (BECAUSE), Magura HS-33 yellow goes with everything, blue RS SID goes with everything, Red Rockshox Lyrik/BoXXer go with everything etc...

peecee wrote:

RS had a red spring in the late 90's

Mandingo915 wrote:

Anyone know how easy it is to strip the paint off all of these springs?

Simple, I have a media blast cabinet.

But try some aircraft paint remover to remove it chemically.

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5/13/2020 12:35 AM

baronKanon wrote:

I see what they are trying to do here. First we had Öhlins who have their signature yellow spring. Then Fox with their signature orange spring. Then Rockshox came along with their signature red spring. Formula have shown their purple spring and now DVO with their green spring. It's like purple anodizing goes with everything (BECAUSE), Magura HS-33 yellow goes with everything, blue RS SID goes with everything, Red Rockshox Lyrik/BoXXer go with everything etc...

peecee wrote:

RS had a red spring in the late 90's

Mandingo915 wrote:

Anyone know how easy it is to strip the paint off all of these springs?

Im sure most companies just make a black version

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