Fork Preload

[xa-mont]

Hey guys,

Got around to setting sag tonight on my forks (05 GSXR 600 Showa's) and shock (06 ZX10R).

Shock was spot on right off the bat. (35mm rider sag, 10mm static sag)

Forks however were a different story, i have the preload wound all the way in and i still have shitty numbers. (40mm rider and 15mm static)

I am thinking this means i need a stiffer spring in the front??? is that right???

Does having the preload wound all the way in cause any issues?

Also with my testing i locked up the front quite a few times under heavy brakes... so i think a better front tyre is in order (got some metzler thing on there now)

[xa-mont]

BTW, i also tried the cable tie method on the forks and it still bottoms out with full preload (and a little endo)

[oldskool]

Try more fork oil Suzuki's tend to not like heaver for oil so make sure the oil is fresh and make the air gap with spring out a little less ie more oil not too much but have a play.

[DiscoDan]

don't give up on the tyre yet, it will be locking because it's bottoming out and has no more suspension travel to absorb the bumps

[xa-mont]

i am getting a new rear tyre soon anyway (my wear indicators have somewhat disappeared), so figure i may as well get a front at the same time.

[oldskool]

I only use Pirelli tires now super corser like shit to a.

[scotty]

i just got my supers for my RGV, there the SC ones, hooooooowwwwwllly fark there sooooo sticccckkkyyy(and my pants)

[crazymofo]

are you un-weighting the front end to get your over all free length measurements on your forks?

if so, subtract 15mm from that number then reset your sag from that, the showas on the late model gixxers and hondas have piss weak top out springs that are quite long. they can give a false free-length measurement. so if the free length is 140mm, minus 15mm, giving you 125mm true length, set sag show 90mm of fork left (35mm of sag). job done.


put a cable tie on the fork leg, and tune excess fork dive with compression damping, you should have about 8-9mm of fork left from the top of the bottom of the forks and the top of the cable ties after a hard ride.
set rebound fairly quick/soft as the showa's are pretty slow to rebound on fast repetetive bumps.

the more preload you set, the less, small bump sensetivity you will have.

the zx10 rear shock is fairly light on its rebound, give it a little more.

test and set both front and rear rebound by pushing down on either end and observing its return rate, it should be as fast as posible with out over extending and then re-settling (double movement)back it all the way off, and keep adding till the re-settling stops. once done go ride and fine tune as you go.

cheers.joe.

[xa-mont]

Thank for the advice mate, i will give it a go tonight with a little more compression damping and see if i can get rid of the bottoming out (that is my main concern).

One thing that i forgot to mention is that the front end only saw about 5-10mm of difference in rider sag from the soft side of half way to fully wound in hard, does this indicate another problem?

[crazymofo]

yeah its the fucked top out spring they put in them.

what i suggested about preload on the front is from my personal experience racing my gsxr 1000 with 09 600 forks fitted (same set up as your forks)
but this page from racetech should help you understand...
http://old.racetech.com/popupwindow/preload.asp


cheers.joe.

[xa-mont]

Thanks a lot for the info mate, i'll have a fiddle with it tonight.