Stack Differences

I switched my MV from:

Piston

20 .11 x5

18 .11 x2

11 .25 x2

17 .30 x3

collar

8 .15 6id

to this:

20 .11 x3

18 .11 x2

16 .11

14 .11

11 .25 x2

17 .30 x3

collar

8 .15 6id

Bike is an '08 yz450f. Fork springs are .48, shock spring is stock (5.5 i think). Im 170lbs, intermediate mx. Im thinkin it should now have a little less ls comp. but gaining some hs comp?? Float is .20 on both setups. Was blowing through the stroke a little on the first stack so im hoping the second stack will help. Any opinions?? Depending on how it feels tomorrow, im already thinking i may want to add another face shim, and close the float up to .15 but i'll start with what ive got. Thanks in advance for your opinions :smirk:

at least you softened the stack

i'm not sure whether that's what you was looking for

A shim stack is linear. So you can't make a difference in high and low speed damping this way.

If the stack bottoms on the 17 0.30's you could gain high speed damping by reducing the opening distance.

With your stack you only make the bending line rounder. I think you won't feel it.

when ever you remove face shims on a mid you are always going to loose both high and low speed damping even with more shims in the taper

if you are 170, and running a 5.5kg shock spring what are your sag #'s?

are they within spec? 5.5 seems a little stiff for your weight. you may want to go with 105mm-108mm. then check the static numbers to see if the spring is right for you.

also, the pivot shim (clamp) in the mid is having an effect on the stack stiffness in the mid. if you add taper, the stack does become softer, but if you change the clamp, you can stiffen the stack that way as well. imho of course.

Hhmm. So what if I add back the two face shims, and take out the 16 .11? Then I would have the five original face shims in there, and my float would change from .20 to .10?? From the original stack with the five face shims, i was looking for a little bit more damping everywhere, and for the forks to stay a little higher in the stroke on downhill heavy breaking. Would closing the float to .10 be too gnarly of a change? Thanks for the input btw.

Sag #'s are fine, cant remember exactly but they were within spec when I got my suspension back form the Company that originally revalved it for me.

if you want to hold the fork up more, you should close the float but dont increase stiffness. Only close it by the minumum amount as it soon adds to the stiffness.

I switched my MV from:

Piston

20 .11 x5

18 .11 x2

11 .25 x2

17 .30 x3

collar

8 .15 6id

to this:

20 .11 x3

18 .11 x2

16 .11

14 .11

11 .25 x2

17 .30 x3

collar

8 .15 6id

:

I would set you up this way.

mid

20.11x4

18.11x2

16.11

14.11

11.25x2

17.30x3

float .15

rebound

20.1x4

13.1

18.1

16.1

14.1

12.2 or 12.1x2

base

32.11x20

30.11

28.11

26.11

24.11

22.11

20.11

18.11

16.2

no passives on comp adjuster

if to stiff pull 5 of the 32.11 and re-test.

350cc outer

comp 10 R 10

.48 springs

455, The MV comp stack you suggest is exactly where im going next i think. Rode yesterday and i can tell you that even though the second stack was in fact I little softer, it had much better action all the way through the stroke. It was too soft for me, and didnt keep the front end up like I wanted under hard braking, but it didnt bottom hard at all. In fact, I was purposely over jumping a step down and landing in the flats on the front end and even though it bottomed, it just seemed to kiss, not CLANK!! A smaller float to keep it up, and one more face shim to add a little more damping everywhere I think will be a super good setup.

dustin, bottoming isn't controlled by the mid (ok, that's not 100% true because everything plays together).

But what you experienced and analyzed correctly is the diving of the front end when braking.

That's exactly what is pretty much influenced by the mid

I realize that as well. I just wanted to inform some folks that even though the stack was a bit softer, it didnt blow through the stroke near as bad as the first stack does. Also, even coming into turns lower than before, it wasnt harsh deep in the stroke at all like the first stack tended to be. I was just pointing out that IMO it is a better MV setup than stacking the face with little taper like the first setup, thats all. i was thinking that since the stack is softer, that it would blow right through the stroke and bottom harshly, and it didnt. Thanks for your input though, I have def learned a ton in the last few weeks.

Dustin, list your current base stack and passives if any?

BV looks like this;

piston

32 .11 x16

30

28

26

24

22

21

20

19

18 .15

17 .25

20 1.6 washer x2

11 .25

BV looks like this;

piston

32 .11 x16

30

28

26

24

22

21

20

19

18 .15

17 .25

20 1.6 washer x2

11 .25

Looks fine and should work well once you add that extra 20.11 to the mid. :smirk:

Thanks for your input 455. Im thinking it will be dialed now for sure!

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