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      05-26-2017, 02:51 PM   #1
d00bies
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jrz rs2 coilovers are bouncy

A lot of people say these coilovers are really good. I installed them on my f82 and the front is pretty bouncy. I maxed out rebound and compression up front. Is there something im missing? Still has about 1 finger gap so its not lowered all the way. Anyone know the stock spring rates on the jrz rs2 coilovers? Thnking about getting some stiffer springs.
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      05-26-2017, 02:54 PM   #2
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You probably adjusted the rebound in the wrong direction is my guess.
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      05-26-2017, 03:22 PM   #3
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First, there's no need to max out R and C damping on the street (and track), plus higher damping is not always better. Adding too much C damping on the street will make the car "bouncy". What are your spring rates? For now, try setting R at the middle setting and then set C ~3-6 "clicks" below the middle setting. R at the middle setting still may be too much for the street - if you lower the R setting always set C to a lower setting to minimize "bouncyness". FYI, this is not how you'd setup (or start to setup) the suspension for the track.
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      05-26-2017, 03:25 PM   #4
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Quote:
Originally Posted by d00bies View Post
A lot of people say these coilovers are really good. I installed them on my f82 and the front is pretty bouncy. I maxed out rebound and compression up front. Is there something im missing? Still has about 1 finger gap so its not lowered all the way. Anyone know the stock spring rates on the jrz rs2 coilovers? Thnking about getting some stiffer springs.
On the street, stiffer springs will not reduce the "bounciness"; a softer spring will smooth out the bounce. I've seen JRZ RS2 come with different spring rates but mine was: Front 500lb main spring + 150lb tender spring. Rear 700lb main spring.

I swapped my front main spring to 350lb. It's a bit too soft. I suggest a 400lb would be perfect for the street.

But before you go that route, try adjusting the compression/rebound on the rear first. This will eliminate almost all the "bounce". Start from this and adjust to taste...

STREET SET UP

FRONT
Compression: 5
Rebound: 9

REAR
Compression: 2
Rebound: 5

Note: 0 is full soft
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      05-26-2017, 03:27 PM   #5
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      05-26-2017, 06:32 PM   #6
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Quote:
Originally Posted by exo-shell View Post
On the street, stiffer springs will not reduce the "bounciness"; a softer spring will smooth out the bounce. I've seen JRZ RS2 come with different spring rates but mine was: Front 500lb main spring + 150lb tender spring. Rear 700lb main spring.

I swapped my front main spring to 350lb. It's a bit too soft. I suggest a 400lb would be perfect for the street.

But before you go that route, try adjusting the compression/rebound on the rear first. This will eliminate almost all the "bounce". Start from this and adjust to taste...

STREET SET UP

FRONT
Compression: 5
Rebound: 9

REAR
Compression: 2
Rebound: 5

Note: 0 is full soft

I tried this set up too. Ended up doing 15 rebound and 9 compression in the rear. The rear is perfect. But the front I've tried all the settings recommended on the forum. Still pretty bouncy at slow speeds. I like to ride pretty stiff, even for daily. I'll try to lower down the compression in the front and see how that goes. So far not really happy with these coilovers, it might be the settings but if its not, definitely not good coilovers for track. I've used a lot of different coilovers in my life, so i know what good coils feel like. Figured i give these a try since everyone on here says theyre one of the best for the f80 chassis.
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      05-26-2017, 07:25 PM   #7
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Quote:
Originally Posted by d00bies View Post
I tried this set up too. Ended up doing 15 rebound and 9 compression in the rear. The rear is perfect. But the front I've tried all the settings recommended on the forum. Still pretty bouncy at slow speeds. I like to ride pretty stiff, even for daily. I'll try to lower down the compression in the front and see how that goes. So far not really happy with these coilovers, it might be the settings but if its not, definitely not good coilovers for track. I've used a lot of different coilovers in my life, so i know what good coils feel like. Figured i give these a try since everyone on here says theyre one of the best for the f80 chassis.
If you say you've tried the exact settings I posted and it still didn't work out for you, then I don't know what to tell you. This is the setting I've been running on my JRZ RS2's for the past year and my F80 is really quite comfortable and flat. Justin at Auto Talent has ridden in my car and can attest to this.
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      05-27-2017, 08:01 AM   #8
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Quote:
Originally Posted by d00bies View Post
I tried this set up too. Ended up doing 15 rebound and 9 compression in the rear. The rear is perfect. But the front I've tried all the settings recommended on the forum. Still pretty bouncy at slow speeds. I like to ride pretty stiff, even for daily. I'll try to lower down the compression in the front and see how that goes. So far not really happy with these coilovers, it might be the settings but if its not, definitely not good coilovers for track. I've used a lot of different coilovers in my life, so i know what good coils feel like. Figured i give these a try since everyone on here says theyre one of the best for the f80 chassis.
What are your current spring rates? Do you have the RS2 Touring or RS2 Sport dampers? The damping of the Touring version is setup to be more street friendly and, therefore, cannot handle higher spring rates.

How slow is "slow speeds"? If you're talking speeds < ~10 mph, especially when coming to a stop, higher-end track-biased dampers can have a bouncyness feeling under these conditions. It certainly doesn't mean the damper won't perform well on the track.
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      05-27-2017, 08:51 PM   #9
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Give it more rebounds.
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      05-28-2017, 09:28 PM   #10
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Bouncy huh...

First let's confirm that you're adjusting the dampers in the correct direction. Full soft is clockwise, and full stiff is counter clockwise. JRZ is backwards compared to most manufacturers.

Next, as a test, set the compression to full soft and set the rebound to 50% aka 12 clicks out / counter clockwise.

Lastly, make sure your tires are set to an appropriate pressure, likely in the low to mid 30's.

This setup should feel 'soft' during bump soak up, without post-bump oscillation.

What's difficult to articulate is how you define 'bouncy'. For some people that could be excessive damping in the chassis while for others it could be too little damping. Try to really describe what's not working the way you expect. The RS twos have a lot of damping range so I'd be very surprised if you're looking for something with even more rebound damping force.
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      05-30-2017, 12:40 AM   #11
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Quote:
Originally Posted by d00bies View Post
A lot of people say these coilovers are really good. I installed them on my f82 and the front is pretty bouncy. I maxed out rebound and compression up front. Is there something im missing? Still has about 1 finger gap so its not lowered all the way. Anyone know the stock spring rates on the jrz rs2 coilovers? Thnking about getting some stiffer springs.
Find out what front and rear rates you ordered your kit with then we can chime in on suggestions. Hold of on stiffer springs until you can figure out why your car is "bouncy".
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      05-30-2017, 10:16 AM   #12
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Quote:
Originally Posted by d00bies View Post
I tried this set up too. Ended up doing 15 rebound and 9 compression in the rear. The rear is perfect. But the front I've tried all the settings recommended on the forum. Still pretty bouncy at slow speeds. I like to ride pretty stiff, even for daily. I'll try to lower down the compression in the front and see how that goes. So far not really happy with these coilovers, it might be the settings but if its not, definitely not good coilovers for track. I've used a lot of different coilovers in my life, so i know what good coils feel like. Figured i give these a try since everyone on here says theyre one of the best for the f80 chassis.
Are you using the Touring or the Sport kit? If you're on the Touring with the stock springs, I think I know exactly what you're talking about.
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      08-23-2019, 10:30 AM   #13
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Hello, hate to revive an old thread but better than starting a new one right? Anyways, I recently installed the jrz RS two touring with GC plates. I'm also experiencing alot of bounce at low speeds. The high speed rebound seems fine but the high-speed compression can also be felt over small shallow bumps on the highway.

My kit has no helper springs, so only the stock jrz rates. My stripped dc5 track car on inferior fortune autos feel less bouncy without too much bump.
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      08-28-2019, 04:05 PM   #14
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Quote:
Originally Posted by 991dc5 View Post
Hello, hate to revive an old thread but better than starting a new one right? Anyways, I recently installed the jrz RS two touring with GC plates. I'm also experiencing alot of bounce at low speeds. The high speed rebound seems fine but the high-speed compression can also be felt over small shallow bumps on the highway.

My kit has no helper springs, so only the stock jrz rates. My stripped dc5 track car on inferior fortune autos feel less bouncy without too much bump.
I had the same issue with both the RS ONE Touring and the RS TWO Touring, though it was a bit better controlled with the RS TWOs. The front end was always very, very twitchy. Pretty much constant small/short twitches as opposed to big/long bounces...if that distinction makes any sense. I tried pretty much every setting I could and I never found a way to "quiet" it down. No matter how stiff or soft I set the dampers, I always had that twitchy feel. I wonder if the Sport kits with the linear springs are just a bit better behaved in that regard?
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      09-09-2019, 06:03 PM   #15
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Quote:
Originally Posted by 991dc5 View Post
Hello, hate to revive an old thread but better than starting a new one right? Anyways, I recently installed the jrz RS two touring with GC plates. I'm also experiencing alot of bounce at low speeds. The high speed rebound seems fine but the high-speed compression can also be felt over small shallow bumps on the highway.

My kit has no helper springs, so only the stock jrz rates. My stripped dc5 track car on inferior fortune autos feel less bouncy without too much bump.
Did you get your RS2ís through the Apex group buy? I have that exact same setup and have the same symptoms. I just had the fronts put on a shock dyno and we discovered they were valved extremely soft causing the low speed bounce. They were so soft the tech though I had them custom valved that way. He said the RS2ís donít normally come that way so it could have been just the production run for the group buy.
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      09-10-2019, 11:38 PM   #16
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Quote:
Originally Posted by bravehart38 View Post
Did you get your RS2ís through the Apex group buy? I have that exact same setup and have the same symptoms. I just had the fronts put on a shock dyno and we discovered they were valved extremely soft causing the low speed bounce. They were so soft the tech though I had them custom valved that way. He said the RS2ís donít normally come that way so it could have been just the production run for the group buy.
Hey man, no I did not get it from the group buy. It was just a standard jrz rs2 touring kit and I got the GC plates afterwards. I called jrz USA and Brian told me to try this setting for street: Front: +8 rebound +6 compression Rear: +7 rebound and +4 compression. It did make a difference however the bounce still exist. I am getting used to it, hopefully the trade off at the track would be worth it. Kinda wish I went with AST or other comparable brands at this price point.
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      09-11-2019, 08:01 PM   #17
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If MCS offered coils without the need for camber plates that would be my first choice.

That and Tractive set.

There has to be a remedy for the bounce with the JRZ considering the cost.
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      09-11-2019, 08:32 PM   #18
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Iím getting the fronts revalved. The rears seem to be ok. I have a half track day Tues so Iíll report back how they feel both on and off track.
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      09-11-2019, 08:35 PM   #19
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Kinda sux all the money I saved on the group buy Iíve spent fixing a brand new set of coils overs.
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      09-16-2019, 05:29 PM   #20
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Quote:
Originally Posted by bravehart38 View Post
Kinda sux all the money I saved on the group buy Iíve spent fixing a brand new set of coils overs.
So did you find out from apex if your rs2 had the touring or the sport valving? I feel you man keep me posted on how things work out. The bounciness is getting old since I daily the car and my friend on stock struts and swift springs ride better.
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      09-16-2019, 07:14 PM   #21
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Feel the same way about my rs two kit. Very bouncy. Still playing around with the settings and using other members suggestions. Worry it's the reason I've gotten some terrible creaking noises from the dash.

I'm also getting some knocking noises from the front end, but when I jack it up, it's all in place and nothing can really be moved by hand. I'm using the ground control camber plates.

Not super pleased, but will keep at it until I've done all I can do.

Since doing so, I've been asked by two bimmer shops why the hell I would mess the stock suspension at all considering bmw's efforts in tuning it with edc. I'm starting to wonder myself
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      09-17-2019, 10:14 AM   #22
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I had a set and they were the same way. You could feel the car continue to bounce at stop signs. Not nearly enough rebound. I bought them used and figure they must have had touring valving.

Finally ended up on MCS doubles and these are much better (and can be easily rebuilt in the USA).
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