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Offline triple_kid

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Re: How suspension and geometry works
« Reply #10 on: July 06, 2010, 01:43:02 PM »
thanks for the advice thirdway. I'll give that ago  :028:
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Offline Mackeral_Fillet

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Re: How suspension and geometry works
« Reply #11 on: July 11, 2010, 04:48:43 PM »
*Originally Posted by thirdway [+]


Daytona forks have poor high speed damping which makes things quite harsh. You can drop off the compression damping which should help a bit, but really they need to be revalved and resprung to suit your weight.

Hiya. Triple_Kid has the 09 forks which are much better than the previous Daytona set. I dont really think they need to be resprung/revalved to be fair, but obviously that would improve what is already a great fork.

Cheers :)

Offline triple_kid

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Re: How suspension and geometry works
« Reply #12 on: July 24, 2010, 06:05:44 PM »
im still not 100% sure i understand what pre-load is used for. There seems to be conflicting statements. From what I can tell preload is exactly what it says... additional force applied to the spring so in effect it has less distance to travel before it absorbs the movement from the forks??? AM i right in thinking if I was to remove preload this would not have an effect on the stiffness of the springs just the amount of travel before the springs "loads" and compression damping kicks in and stop the forks from bottoming out?

The daytona forks do seem to be a bit on the stiff side compared to the standard ST offering. Ive taken one click off the rebound and wound half a turn of preload to give a bit more static sag. The daytona forks are awesome when pushing on but can feel harsh at sedate speeds 30-50. I was thinking of taking slow / high speed compression... thinking to try slow speed compression first as at speeds the forks do there job magnificently.

What am i best adjusting, compression / rebound to slightly soften the forks?

MY HEAD HURTS  :087: :087:
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Offline triple_kid

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Re: How suspension and geometry works
« Reply #13 on: July 24, 2010, 07:25:10 PM »
*Originally Posted by nikko [+]
I said right from the off that this thread shouldn't be a sticky because its too ambiguous.  No criticism of 3way whatsoever, its bloody hard to nail this subject because the parameters are so variable.


But a tec sticky has to be spot on IMO because being a sticky implies credibility.


Triple kid, rather than just give my take I'll post up a linky - when I can find the ####  :038:






Thanks Nikko... mutchas gracias  :031:
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Offline triple_kid

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Re: How suspension and geometry works
« Reply #14 on: July 25, 2010, 12:20:49 PM »
can anybody tell me at what speed does high speed compression take over low speed comp???

the daytona manual says sweet FA about it  :027:
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Offline thirdway

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Re: How suspension and geometry works
« Reply #15 on: August 16, 2010, 06:36:32 PM »
*Originally Posted by nikko [+]
its not the speed of the bike.............its the speed at which the suspension operates internally ie compression rating

start here, some of this is spot on

en.wikipedia.org/wiki/Suspension_(motorcycle)

still tryin to find the other one..........

What he says but a bit more.


Slow speed compression effects the braking and cornering forces applied to the bike. In other words, less compression means more dive on the brakes and likewise with geometry changes in corners.

High speed compression is more about comfort.It's the way the suspension reacts to high frequency bumps. The harder the suspension is set, the more it kicks off bumps/jars wrists etc.

The main thing you need to know about pre-load setting is that it should be adjusted to givethe right amount of sag for rider and machine (plenty written above about where that needs to be). If you can't get it close to these measurements then you need to have a new spring fitted.

One last point on the compresion damping. It's rare that a manufacturer will give you much latitude for adjustment (infact my speed triple had the twiddly bits but they didn't actualy give any adjustment whatsoever). The reason is that they don't want you altering the handling so dramatically that they get sued. Modified forks from the like of Maxton have huge adjustability and come with explicit warnings about straying too far from their preferred set up.
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Offline specky

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Re: How suspension and geometry works
« Reply #16 on: November 13, 2010, 11:17:52 PM »
I found a good way of balancing the preload between front and rear when I was adjusting my head light beam height. I found if i sat on my bike with the head light beam on a wall the beam would raise suggesting the rear was softer than the front. I raised the rear preload in small amounts until the rear did not squat any more. This has worked a treat for me as it has cured my bikes tendency to run wide in bends while accelerating.

Offline Rockbob

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Re: How suspension and geometry works
« Reply #17 on: December 14, 2010, 01:22:40 PM »
Hi very interesting thread i have been riding bikes for years and am ashamed to admit suspension set up is a mystery to me.
A couple of years ago i had a 05 Ninja which was bloody awful on rough bumpy roads and twitchy on corners, a friend of a friend of a friend  put me touch with a guy who used to be a race mechanic (cant remember which team it was) who for a few "sheckles" would help set the bike up for me, the first thing he did was put me on a set of scales noted how much i weighed and put the bike back to factory settings we then went for a ride, after the test ride which he followed on his zx10, and on my response to questions on how it felt and what he had seen he adjusted both front and rear the result after a few more micro adjustments was amazing i felt like the king of the road the bike was so stable and confidance inspiring. 
" If Your Ears Don't Bleed It Ain't Rock & Roll"

Offline Rockbob

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Re: How suspension and geometry works
« Reply #18 on: December 14, 2010, 05:37:19 PM »
 :431:not sure what happened to the rest of my reply.................. but i wanted to say the morole of my tale was if you don't fully understand how suspension works leave it to someone who does !!!
" If Your Ears Don't Bleed It Ain't Rock & Roll"

Offline williamr

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Re: How suspension and geometry works
« Reply #19 on: January 11, 2011, 11:16:58 AM »
Without getting involved in the complexities of setting up suspension, pre-load has one very simple job.

It's there to ensure that the shock is within its correct operating range, so that it neither tops out nor bottoms. With rider and bike supported by the suspension it should have an amount of sag equal to about 1" or 1/3rd of its operating range. The fact that it does alter the ride height is no relevant. It should not be used to alter the ride height, although many riders do use it that way. Neither does it alter the spring rate.

If you're riding on roads smooth enough that the full operating range of the shock isn't used you can use pre-load to tweak ride height a little, but that isn't its intended use.

By altering ride height at the rear you're effectively altering the steering geometry - the head angle and trail. That's best done by adjusting the front fork height, keeping geometry changes and suspension changes seperate.

So with preload (sag) and steering geometry set, you can then play with the real suspension settings of damping and spring rate (but altering spring rate - usually be replacing the spring unless your forks are air assisited) will require re-setting the sag.

Rob

 


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