KahnBB6

iTrader: (5)

I've posted a bit here about the Gixxer_Drew suspension in the past and recently. I love how it rides and I've been very happy, but I do have one minor issue that seems to have become more frequent now. This may or may not have to do with some bad sections of road on my usual routes now.

I have not lowered the car much at all. It's a 600/325 version that I installed in 2010 before it came to light that helper springs were probably needed with ALL Gixxer setups including 500/250. This wasn't explicitly in the instructions in 2010.

Preload was VERY hard to achieve upon installation but, again, as per where the discussions in the Gixxer_Drew thread on SF went, this didn't seem to be much of an issue. Now I think it actually is.

I am getting a rear clunk that sounds like a spring but it simply comes off as "PONG!". It happens nearly every time I drive now. It isn't the shock tower perches and I can't see anything that looks amiss when inspecting the right rear of the car. Believe me, I looked for every single correct torque spec I could find when installing both this suspension and my TT sway bar.

Despite this, the car drives perfectly and even after getting it aligned it doesn't exhibit any strange handling characteristics at all.

Is this the custom suspension or is there perhaps a need to replace the used rear swaybar endlinks or another part of the factory suspension?

Another thing is that I installed a set of M2 dual catbacks a few months ago. I wonder if those pipes being of a slightly different bend and hitting some part of the suspension could be causing this as well?

Any educated guesses would be appreciated guys. Again, other than this occasional PONG noise there aren't any issues with handling or strange unpredictable behaviors. Just the noise.

Da Coupe

iTrader: (7)

Hey Kahn, I love the gixxer setup. I went with 500/250 and it's perfect for the street. Better than others I've tried like tein cs, tein flex, and cusco zero 2r. I'll never go back to jdm coilovers. But I do get the clunk when going over speed bumps from front and rear. I do have preload set as Drew prescribed and I rock a bone stock ride height. I'm getting the car corner balanced and aligned this week and might go 1" lower. Don't want to compromise the suspension geometry but I don't think an inch will hurt. I do have to admit I love being "high". I plow through all the bumps.

INTIMAZY

iTrader: (5)

Not sure what the nature of this clunk is. I've had my 500/250 setup a few months now and am actually lowered ~1.5" from stock ride height with no clunks or need for helper springs. Spring preload is basically zero when suspension is hanging. I have the spring perches adjusted to just the height where the spring sits in the perch and hat without any slop. No need for helper springs since the spring is fully seated even when hanging. This is all with the 'newer' style Supra shock that may or may not have a longer shock body. No rubbing in the fender, although the harness is relocated anyway just to be safe.

I would check endlinks especially if you have sway bars. They are a major cause of suspension noise in general.

Da Coupe

iTrader: (7)

Yea the clank boggles me. I have sufficient preload which makes me wonder why it would clank. I suspect the coil over sleeve is hitting on the shock body. I've seen some ground control sleeves with rubber grommets that go between the sleeve and shock. I might try that when I get a chance. After more driving through speed bumps it's actually just coming from the fronts. It's more like a quick rattling.

INTIMAZY

iTrader: (5)

I have cheapo ebay sleeves and they are SNUG! Especially with the dust cap banged firmly on top of them.

Did you cut the sleeves? Mine didn't need cutting on the lower c-clip shock groove

Da Coupe

iTrader: (7)

Yea mine were cut by the previous owner. Good to hear yours don't make any noise cuz mine bugs the crap out of me. I'm starting to wonder if it's the preload. Everyone on here and SF is lowered with no preload (I don't think helper springs add much preload compared to actual springs but just keep the springs seated) and don't have the clunk or clank.

KahnBB6

iTrader: (5)

Hey DaCoupe! Good to hear you're enjoying it. As I mentioned, so far I am still okay with 600/325 for the street but I have also given thought to going to your spring rates as I will be returning to L.A. later this year. Personally I'd go with a good JDM coilover system but from my research this was a budget-friendly and excellent alternative for roughly $1k. I'm very happy with it.

But you and the others in this thread have described a "clunk". Mine is more of a pronounced "PONG!" from the right rear shock area. I originally theorized this was due to the springs there reseating since there was almost no preload (no helper springs on mine with the newer and longer Bilstein design). Now I have a new theory: since my bump stop appears to have fallen from the shock top hat area to the shock piston area, I actually think it's getting caught between spring compression states and is popping around in there-- hence the "PONG!" noise. I need to check it thoroughly to confirm that.

I definitely don't have a "clang", "clunk" or "thunk" noise from the suspension. Occasionally from my Torsen LSD, yes (and I won't get into this here but it's fairly normal operation for that component).

Other than that noise I am experiencing ZERO handling issues or irregularities. The suspension works very well for what it was designed to do.

INTIMAZY, I will check my rear endlinks. Those were not replaced when I swapped in my Supra TT rear sway bar and they may be due. I can't remember if I need the SC endlinks or Supra TT endlinks or if that even matters. Research time soon.

LEXXIUM

iTrader: (1)

I have the same issue, I haven't looked into it but my end links are old and exhaust is fat enough to hit the sway bar on certain ocations.
I'd replace end links first and go from there, how are your rear sway bar bushings?

KahnBB6

iTrader: (5)

LEXXIUM, my rear swaybar bushings were brand new TT pieces when I did that swap. So we're the subframe mounts. Swaybar end links were reused but so far I've never had a technician point then out as worn during an alignment.

Da Coupe

iTrader: (7)

Hey Kahn I figured out my clanking issue. Totally unrelated to the coil overs. Sometimes my ears play tricks on me. As for your issue... is the bump stop really that big to get caught on the coils? And how much preload are you putting? I think with your spring rates a snug fit with the collar would do. I ended up using koni progressive bump stops meant for the Nissan SE-R which fit perfectly. I've also been thinking about revalving my bilsteins to handle 20% stiffer springs but still use the 500/250 setup. I don't think that's ever been done. Subaru Sti's use under 300lb rates fr/rr and feel great on the street. I'm guessing its the aggressive dampening..

INTIMAZY

iTrader: (5)

All Bilsteins are pretty overdampened from the factory. It's the nature of the beast. Revalving for a 20% stiffer spring would not be useful for handling nor ride comfort.

Also keep in mind, the location of the spring affects the effective spring rate. Can't compare an STi spring rate to our double A-arm since they use a strut up front. Same goes for Mustangs. They used to use 250lb springs up front as an upgrade!!!