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Hey guys i just bought some 2nd hand koni spring shock combo and the springs are blue ish kind of like the picture below.
Have koni written on them but no matter were i look on the internet i cant find spring rates for them.
Does anyone have any data ?
Thanks

Any alphanumeric printed on the outside of the springs?

koni 110 on the rear
and koni 109 on the front

Ring KINGS springs on the Gold Coast, usually very helpful and give them the numbers.
Cheers

There not king springs tho
kings are yellow
these have koni stamped on the springs

How's your German - here's the Koni manual for them: <www.koni-rus.ru/manuals/koni_1110-7030-tuv.pdf>

trying to translate now wish me luck lol
thanks mate

mx589 wrote:There not king springs tho
kings are yellow
these have koni stamped on the springs

I fully realize that they are not KINGs springs however they could shed some light on the KONI numbers

If you can do basic maths, have vernier calipers & a calculator it's easy enough to work out:

k = (W^4 x G) / (8 x D^3 x N) or written out k = (W x W x W x W x G) divided by (8 x D x D x D x N)

k - spring rate (lb/in)
W - wire diameter (in)
G - 11,000,000 (psi) - close enough for spring steel modulus of rigidity
D - PCD of Coil (in) i.e. coil outside diameter minus wire diameter
N - number of active coils = 6.5 by your photos

The photo shows all springs have 7.5 total coils. The ends closest to camera are open, but the far ends look to be closed (hard to tell in photo)
If both ends are open N=7.5, but if one end is closed, N=6.5.

Sorry to work in lbs & inches, but I'm old school

ahhh wasp ic ic may call them this week then
rs2000 wow 2 many numbers im lost already
That german pdf i google translated some of it and not anything in there about spring rates that i could see

RS2000 wrote:The ends closest to camera are open, but the far ends look to be closed (hard to tell in photo). If both ends are open N=7.5, but if one end is closed, N=6.5.

Tops appear to be closed from following pic: http://contour.org/ceg-vb/forum/modific ... rings-info

Thanks for the link
they are the same springs as what i have

Yeah, believe they're the Koni recommended springs for the MX5 NB.

Thanks for the info mate

I was looking for the same information but unable to find it, so ended up measuring the set I had and thought I'd put the info here for anyone looking for it in the future...

Front - Koni 109
Wire diameter 0.465 inch (11.8mm)
Coil OD 4.135 inch (105mm)
Active Coils 5.75 (The top and bottom spring platforms "deactivate" about a full)

Rear - Koni 110
Wire diameter 0.425 inch (10.8mm)
Coil OD 4.135 inch (105mm)
Active Coils 6 (The top and bottom spring platforms "deactivate" about a full coil)

So using RS2000's formula we end up with
Front 226 lb/in (4.0 kg/mm)
Rear 146 lb/in (2.6 kg/mm)

which fits in nicely with the usual 3:2 ratio on the front to rear rates.