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hmmmm..... marketing ploys maybe..  I just go by what i've been told.  so sorry if it's inaccurate -- ill have to speak to guy who told me that in the first place.

fair comment though.  Is there any difference at all between the two methods? 

There are quite a few major brands being released with both methods of adjustment these days.  is this just so you can go lower?  what's the story there...

sorry if i touched a nerve there,  though, what i said was what i've heard from a few people,  so may be some bad info going around there.

From a purely suspension engineering point of view the need for adjustment of the length of the shock is very simple. As usual it boils down to cost cutting.

For example, R32/33/34 Skylines have a number of different lengths of shock absorber, as well as the rear fork/eye differences. This means you have to make a different shock body for each model due to this requirement for different lengths. Bilstein, for example, make 5 different front shock lengths for these models of Skylines. But if you have an adjustable length shock body, you only need one model. Hence cheaper to manufacture, cheaper to ship and cheaper to stock (less required). One shock length instead of five = 80% reduction.

Also if you make the shock bottom interchangeable between fork and eye style, that reduces the number of rear shock derivatives you need to make/ship/carry by 50%.

Now if you add that bottom screw on mount adaptability to other cars, you find quite a lot of interchangeability. So the 80% reduction in manufactured shock bodies numbers may in fact end up many times that. All you need to do is make the adaptors different, not the whole shock. A lot of the cost of making shocks is tooling up to make the shock body, so any reduction in that area is important.

A well known legal requirement is to ensure the springs are trapped at all times, excessively lowering the bottom spring seat can sometimes lead to non trapped springs. This is why flat wire tender/helper springs are used, in extreme cases you may need 2 helper/tender springs to achieve the lowest height adjustment. But if you reduce the length of the shock body you can avoid this need and save the cost of a helper/tender spring. Being flat wire, the cost of making a tender/helper is in fact higher than making the main coil from round wire. So the cost saving from this is very worthwhile.

BUT (there is always a but), the problem is this cost cutting easily extends to the valving. Logically if I have reduced the number of different shock bodies, I will also need to reduce the variety of shock valving to maximise the cost reduction. The thought of an R33GTR front shock running the same valving as an R32GTST is quite a frightening one. Most certainly one that simplistically adjusting the rebound rate is not going to overcome.

The bottom line, it is done to save money.

:angry: cheers :P

I don't believe that sydneykid, even though i'm more knowlegable about motorcycle suspension i believe it would have the same basic principles. Changing the preload on a motorcycle barely affects the ride height at all, but it does make the action of the suspension happen faster. If the spring is compressed more than usual to begin with i'd believe it would compress and uncompress faster.

I don't believe that sydneykid, even though i'm more knowlegable about motorcycle suspension i believe it would have the same basic principles. Changing the preload on a motorcycle barely affects the ride height at all, but it does make the action of the suspension happen faster. If the spring is compressed more than usual to begin with i'd believe it would compress and uncompress faster.

So what you are saying is the spring rate increases as you compress the spring?

Since the spring compresses when you sit on the bike, that means the spring rate is higher with you on the bike than it is with you off the bike?

The spring rate is even higher when you have a pillion, because the spring compresses even more?

Try this test.

1. Put the spring height adjuster on the lowest setting

2. Measure how far off the ground the tailight is

3. Then sit on the bike and measure how far off the ground the tail light is

4. The difference between those two measurements is how much your weight compresses the spring (ie; the spring rate)

5. Put the spring height adjuster on the highest setting

6. Measure how far off the ground the taillight is

7. Then sit on the bike and measure how far off the ground the tail light is

8. If you are right, the difference between those two measurements should be less than that the measurement in #4. ie; the spring should compress less because the spring rate is higher (according to your logic).

Do you want to try the test, or can you already see how illogical your assessment is?

:) cheers :)

Oi, what does this all mean, Can i adjust my suspension so that the ride is less harsher or not???

Cheers

If you have adjustable shock valving, then you can soften the shocks.

That may help, maybe even enough so that you are happy.

But based on other people's experience, that is most unlikely.

The only way to soften the spring rate is to buy lower rate springs.

Springs cost around $100 each, so allow $400 (plus labour if you can't DIY) to swap to lower rate springs.

The alternative is to sell your Teins and take advantage of the Group Buy.

The 4 X Bilsteins and 4 X Whiteline springs will cost around $1100.

You might be able to sell the Teins for $700

So you might still only spend $400 (plus labour if you can't DIY) but you will get new, superior engineered (for Australian conditions) shocks and springs.

Hope that helps

:) cheers :)

PS; if you want to know what your current spring rates are, go to this thread and post up the dimensions and I will work out what the spring rates are for you

http://www.skylinesaustralia.com/forums/in...showtopic=79157

Edited by Sydneykid

i sold my HKS hyper-Ds for 500 plus shipping to a member of this forum, and bought whiteline springs/shocks and new dust covers and also strut tops

all up i think it was about 1250 and i installed myself, so 750 to upgrade the suspension.

dont forget u will need the stock strut tops if your coilovers come with their own, so dont arrange to sell them and get new suspension without them.

btw lately i have seen them for sale on ebay, when i got mine it look me a long time to find a set and in the end bought them of someone off the forum who bought coilovers.

i sold my HKS hyper-Ds for 500 plus shipping to a member of this forum, and bought whiteline springs/shocks and new dust covers and also strut tops

all up i think it was about 1250 and i installed myself, so 750 to upgrade the suspension.

dont forget u will need the stock strut tops if your coilovers come with their own, so dont arrange to sell them and get new suspension without them.

btw lately i have seen them for sale on ebay, when i got mine it look me a long time to find a set and in the end bought them of someone off the forum who bought coilovers.

Hey, ive been driving around more lately and had mates in the car and everyone has basically convinced me that the suspension is MAD and that i'd be an idiot to sell it. Plus i am getting used to the bumpyness, it makes it feel more sporty.

My dad wasn't too impressed though. Theres a funny squeaking noise whenever u go over bumps. My dad reckons that the seals are gone on the shocks but apparently teins have a rep of being really noisy so im not sure. I'll prob take it down to centreline when exams are over, see what they reckon

Thanks for ur help guys, if i decide to adjust the suspension i'll prob just take it down to the mechanics (Pedders are extremely unhelpfull).

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