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that question is valid but sadly still unanswered.

preload destorys small bump sensitivity and should be avoided at any cost. its always better to set ride height via the right spring!
Total bollocks unfortunately. Your spring doesn't know the difference between a small bump when you have 4mm preload and 0 preload. All it knows is your weight already has it compressed 12mm.

No difference in small bump sensitivity.

Spring rate determines frequency response. Preload sets ride height.

Actually no because the Yeti recommended spring for my weight is a 425lb, PUSH wants to put me on a 450lb, I am actually running the spring rate recommended by the people who manufactured the bike...since I'm so slow amd you know so much about this then why did Kazimer test the sb165 at the same bodyweight as me with a 400lb spring... Again you are making assumptions.
Excellent. So is Yeti wrong, is Pinkbike wrong or is Darren wrong? Inquiring minds need to know?

And I encourage you to go back and read what you said about preload.

You make a lot of assumptions and throw a lot of opinions around Dougal without testing the same setups for yourself...you forget you are only running a 5lb heavier fork spring than me on a shorter travel fork.
See above about preload. I have owned and ridden coil spring FS bikes since 1997 and still do today. So I have a little experience there.

Yes I'm riding a firmer spring and getting more travel. You're not past 150mm yet right?

I think everyone in this thread should be banned. Me included, I'll take one for the team to stop this shitshow. 😂
Aww come-on. Where's your commitment?
 

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Discussion Starter · #563 ·
Dougal let me repeat yet again, a riders weight is dynamic on the bike. That's the first point. The second point that I'm sure you bloody well know as a suspension tuner is you don't only ride at sag state or deeper, the wheel goes negative too..when you have negative travel, say for instance a pothole and the tyre is forced by the supension into the ground near to full extension, it then has to compress from that point, if of which it is preloaded has to first reach the amount of force the preload is generating before the shock will start to compress, the faster you go the worse this will get as gravity and your body weight falls at a fixed rate but the fork extends much faster into the hole before your bodyweight can catch up....yet again THE RIDERS WEIGHT IS DYNAMIC ON THE BIKE...anyone would think you only ride around at sag point and stay stuck to the ground with only positive compression, but then again looking at the video you posted, that pretty much appears to be the case with you....
 

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Dougal let me repeat yet again, a riders weight is dynamic on the bike. That's the first point. The second point that I'm sure you bloody well know as a suspension tuner is you don't only ride at sag state or deeper, the wheel goes negative too..when you have negative travel, say for instance a pothole and the tyre is forced by the supension into the ground near to full extension, it then has to compress from that point, if of which it is preloaded has to first reach the amount of force the preload is generating before the shock will start to compress, the faster you go the worse this will get as gravity and your body weight falls at a fixed rate but the fork extends much faster into the hole before your bodyweight can catch up....yet again THE RIDERS WEIGHT IS DYNAMIC ON THE BIKE...anyone would think you only ride around at sag point and stay stuck to the ground with only positive compression, but then again looking at the video you posted, that pretty much appears to be the case with you....
It's like you think sag is a concept I've never heard of and are arguing against. But I'm not. You made that argument up after not reading what I've actually written.

Same for this "THE RIDERS WEIGHT IS DYNAMIC" that you keep screaming about. No-one has ever claimed otherwise.

I have no idea what you're on about or what you're trying to say. This is screaming at clouds tier.

Your idea about preload is however totally wrong. In your example above the spring is already past preload and working normally.
 

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Discussion Starter · #565 · (Edited)
If the riders weight is dynamic, and the rear shock extends to full travel whilst under preload and gets to the portion of the pothole for example where the suspension now wants to compress from top out what do you think will happen? The bump will have to create a force past the preload force before it will compress.

I don't know if you just play dumb to not have to answer the questions or come back with a valid argument but I really can't put it any more basic than that...I'm pretty damn sure most of the other readers here know exactly what I mean...and if they don't, well, some folk can't be helped I guess.

(Danzzz predicts Dougal copy and pastes last sentence and redirects at Danzzz, but won't now as Danzzz knows he would do it) fml as dumb as this thread is, the bs and banter is beyond predictable. Sure a lot are just playing devils advocate...
 

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If the riders weight is dynamic, and the rear shock extends to full travel whilst under preload and gets to the portion of the pothole for example where the suspension now wants to compression from top out what do you think will happen? The bump will have to create a force past the preload force before it will compress.
2.5mm preload on a 400lb/in spring produces a massive 40lb of preload force at the shock. That's less than 20kg. At the rear tyre that's like 6kg before the spring starts to move. At a time when the total bump force is over a magnitude more than that.

It's piss all and is less than the inertia of the rear wheel and bike being accelerated by the bump. The suspension literally blows straight past the preload point and no-one ever notices.
 

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If you have a 400lb spring, and you add 50 lb of preload, the bikes sag decreases. At sag, the next inch of travel will require 400 pounds of additional force.

If you have a 450lb spring and you add no preload at all, the sag will be be the same, and the next inch of travel will require 450 lb of force.

If you need your bike sprung for 400 pounds, but its riding a little too low, you add preload.

Obviously riders have dynamic weight shifts all over the bike. Thats why preload is important, preload doesnt change your base spring rate so your spring reacts how you want during dynamic riding.

That's literally all preload does.
 

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Discussion Starter · #569 ·
Correct it doesn't change the base spring rate, but it does change the initiation force from top out which is my point. The bike during aggressive fast riding over rough terrain will be reaching top out or near to it a lot of the time, if it didn't bike designers wouldn't aim for roughly a 30% wheel sag in the first place.
 

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Thats the thing, it doesnt change the initiation force even remotely. It changes how far the same amount of weight will compress the shock, it doesnt change the shock compressing or not.

Preload is not breakaway force.
 

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but it does change the initiation force from top out which is my point.
That does nothing.

The bike during aggressive fast riding over rough terrain will be reaching top out or near to it a lot of the time, if it didn't bike designers wouldn't aim for roughly a 30% wheel sag in the first place.
Still means nothing.
 

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Discussion Starter · #572 ·
Ffs watch....

Oh and Dougal you know that graph in Andrextr's video when you said anyone can draw a graph...funny, because Steve has drawn the same one... So is Steve wrong too?
 

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All it knows is your weight already has it compressed 12mm.
but what if not... imagine the wheel being in the air and hitting a small obstacle.
yeah it does not make a great deal, but we are aiming for the best, arent we?

i would always try to minimize the offset.
ifp forces are countered by the counter measure spring in rockshox shocks, minimizing preload optimizes your shock further.

Preload sets ride height.
and what would be the right ride height? or do you just want to equalize front/rear to acchieve a given geometry?
 

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Ffs watch....

Oh and Dougal you know that graph in Andrextr's video when you said anyone can draw a graph...funny, because Steve has drawn the same one... So is Steve wrong too?
I don't have the time to watch videos in the hope of finding an argument for you. At the least put in a time-stamp.

How much preload does your car suspension have? Do you have a car?
 

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but what if not... imagine the wheel being in the air and hitting a small obstacle.
yeah it does not make a great deal, but we are aiming for the best, arent we?

i would always try to minimize the offset.
ifp forces are countered by the counter measure spring in rockshox shocks, minimizing preload optimizes your shock further.
The wheel being in the air and hitting a small obstacle doesn't matter.


and what would be the right ride height? or do you just want to equalize front/rear to acchieve a given geometry?
The right ride height is the one that gives you the correct geometry and pedal clearance.
 

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Discussion Starter · #576 ·
And in one simple sentence you just proved you know nothing about the dynamics of riding a bicycle... You just compared a car, or a motorbike if you like to riding a full suspension mtb. No they are not the same thing and require different schools of thought, practically every suspension tuner worth his salt knows this.... That sentence right there Dougal is all I need to know, this conversation need not go any further.
 

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but what if not... imagine the wheel being in the air and hitting a small obstacle.
yeah it does not make a great deal, but we are aiming for the best, arent we?
Using travel for the lowest amount of force isnt the best. Thats why dropping pressure and stuffing a fork full of tokens ends up working terribly. You use tons of travel off the top over tiny bumps, the fork rides excessively low, and you've got nothing but ramp up left to take care of actual obstacles. Having it firmer off the top can increase performance.
 

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Discussion Starter · #578 · (Edited)
Using travel for the lowest amount of force isnt the best. Thats why dropping pressure and stuffing a fork full of tokens ends up working terribly. You use tons of travel off the top over tiny bumps, the fork rides excessively low, and you've got nothing but ramp up left to take care of actual obstacles. Having it firmer off the top can increase performance.
Tokens can't be compared to preload at all, one is changing the shape of the spring curve to be softer and less supportive at the start and middle, the other is limiting the initiation force, which you still seem to be saying isn't true.. I advise you and Dougal both watch Steves video above, and as for Dougal comparing automotive suspension applications to mtb there is no hope, I pitty anyone who sent him a shock or fork to tune... Clearly doesn't understand static vs dynamic sag, and that the rider is a seperate mass to the frame...

In a car or on a motorcycle the vehicle chassis etc makes up the majority of the mass and is all sprung... On a bicycle the rider makes up the majority of the mass, the sprung mass of the frame is relatively light weight compared to the spring rate and riders mass and the rider being detached from the frame means said riders weight is not always in sync with the sprung mass of the bike frame and therefore this means the riders weight is not 'always' sprung mass..aka dynamic. Automotive and MTB suspension applications are different, I literally cannot fkn believe he does not know this...
 

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Discussion Starter · #580 ·
i cant see why i doesnt matter if you look at the shock isolated.

do you mean the effect is neglectable and is overcast by other factors?
Forget what he means, he nailed home in one sentence how little he actually knows about how a rider interacts with the bicycle and subsequent affects on suspension by stating how much preload does your car have. Fml, all this time I thought he was trolling or playing devils advocate, but actually he is just a guy that plays with shims and oils and doesn't know wtf is actually going on.

I'm done here, godbless those who actually believe some of the crap he says and worse pays for his 'expertise'... This is my last post in this thread.
 
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