...although I have to admit that the above had even me scratching my head. Yes, bottoming under load could be fixed by adding preload...but the rest is not sensible (to me).
Understanding Preload
- Thread starter YellowDuck
- Start date
...although I have to admit that the above had even me scratching my head. Yes, bottoming under load could be fixed by adding preload...but the rest is not sensible (to me).
Only if the suspension is topped out...not when there is sag. Please don't argue just for the sake of it!
It depends if we are talking about applying preload to the front or the rear.
At any given position, anywhere between full extension and bottoming out, a preload adjustment will result in a different spring reaction force at that position.
I'm not arguing for the sake of arguing. I'm arguing because some people posting in this thread don't know what they're talking about.
Yeah, the suspension isn't actually preloaded when it bottoms out, it just adds load to the bump stop. So the term was used incorrectly but the point was that we want the load to go through the spring at all times, not the damper body or bump rubbers.
No one is disagreeing with that. You don't understand the premise of the discussion, try bre-reading the thread.
Okay, but aren't you coming at it from an odd direction, to talk about "at any given position" in the stroke? That has nothing to do with whether or not the suspension will feel stiffer in use, because when you add preload you are not operating at the same *position in the stroke*, you are operating at the same *spring compression*. That's the whole point (or at least my whole point in starting the tread), and you just confuse matters by posting quips like "yes it does" when what you mean is "yes it does in a certain technical context that I have in my head but have not shared". That is not helping anyone to understand anything, it is just baiting.
I understand what has been written perfectly well. You've made some completely wrong statements in this thread.
One makes adjustments to spring preload to alter how much fork/shock travel is being used. The subsequent change in ride height is a byproduct of a preload change, not the objective of it. Competent suspenion tuners will compensate for that change in ride height by making sliding the forks up/down in the tripes or by lengthening/shortening the shock.
Your spring preload is present all the time, not just at full extension, and is affecting your suspension at all times.
Actually I have seen installations where there is no preload even at full extension, rightly or wrongly. So are you going to tell me that turning the spring perch in that case has no effect on the suspension tuning, if it doesn't preload the spring?
The question makes no sense. Thats like asking if chain adjusters will adjust chain slack if there's no chain installed. If your spring perches don't contact the spring (at any time) then there is something wrong with your forks. If when fully retraced the perches are just barely touching the spring (effectively no compression) then turning it will compress the spring.. so yes it will preload the spring.
I have never encountered any shock or fork that has no installed preload. It's needed to keep everything in the fork/shock under tension so nothing smacks against anything else inside the fork/shock.
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You've reformulated the question so that turning the spring perch adds preload, but that's not a given. Say you come across a bike with too little sag. Then when you raise it to adjust "preload" you find that the spring sits uncompressed. The adjustment you make will not add or remove preload, so what do you call the adjustment? Answer the question.
That's an interesting analogy I'd like to use.
The analogy is more like improperly calling a chain slack adjustment a chain "tension" adjustment. There is no tension on the chain, there is none added or removed as a result of adjusting, and there is no target tension value being sought. So the correct name is chain slack adjustment, anything else will lead to confusion and misunderstanding.
The same applies to suspension "preload". The spring is not preloaded in normal use, none is added or removed as a result of adjusting, and there is no target preload value to aim for. "Preload" adjustment is the incorrect name. It leads to confusion and misunderstanding, which is what this thread is all about.
Your forks were improperly assembled.. that's what i'd call that.
You're talking about stuff that makes no sense. Forks with zero assembled preload? I've never encoutered anything like that. Never even heard of anything like that. If something does get built like that it was done so in error.
I hope no one believes the misinformation you're dumping onto this forum. I'm not going to try to correct you anymore since you're so determined to be wrong.
This would be indicative of a spring rate which is too high (by a lot).
Or it's free length could be too short. But yeah it wouldn't the optimal set up, but sometimes people have to make do.
