Need Help Suspension experts
#1
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I have BC coilovers on swift springs. My drivers front suspension has developed a dull knock when going over small bumps at very low speeds. At higher speeds 40km/hr and higher, the sound goes away. I removed the top components and torqued to spec. The suspension does not appear to be leaking when I had a look at it on a hoist. I made a few video clips to capture the noise its making.
first clip is one I made in car
second clip is one I made with the phone sitting directly on top of damper corner.
Any suggestions are welcomed......
first clip is one I made in car
second clip is one I made with the phone sitting directly on top of damper corner.
Any suggestions are welcomed......
#5
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I brought my car to a friends house who has a hoist. He took it apart and did exactly that, nothing fixed. The more I search, it appears to be a common issue with the brand and a simple cartridge replacement will do the trick. I emailed BC USA, hopefully they can shed some light.
#6
Tech Info Resource
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You're expecting a lot from a low end piece. Tein is no better. If you want something to deliver, you need to look at Ohlins or Penske. The video alone is enough to make me not want to waste a dime on cheap shocks. While BC might call this good, it's total crap and in no way represents a good way to adjust preload on any suspension device. All it does is sets the bar very low for failure.
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#8
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You're expecting a lot from a low end piece. Tein is no better. If you want something to deliver, you need to look at Ohlins or Penske. The video alone is enough to make me not want to waste a dime on cheap shocks. While BC might call this good, it's total crap and in no way represents a good way to adjust preload on any suspension device. All it does is sets the bar very low for failure.
Last edited by Compthis; 08-30-14 at 10:16 PM.
#9
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The knock issue is usually the upper bushing compression. The center crush tube is just a hair too short for the amount of torque you can put on the nut. So an impact driver (not impact wrench) but something with a much lower torque limit is required to get the stack to compress into the tube. The second thing that sometimes happens is the circlip on the shaft sometimes rolls over which prevent the stack from compressing as well. BC''s are still the best bang for the buck and can be very reliable if this issue is resolved. I think most of the time when people change the spring cartridge, they are reassembling the shock, so it has a tendency to resolve itself just from the re-compression of the bushing.
We just received the Ohlins R&T setup that we have been working on for the past 3 1/2 years Friday. This includes spring rates appropriate for the F as well as new valving. Testing this coming week and might get out the the track on Friday.
We just received the Ohlins R&T setup that we have been working on for the past 3 1/2 years Friday. This includes spring rates appropriate for the F as well as new valving. Testing this coming week and might get out the the track on Friday.
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Redefining Lexus Aftermarket Parts Since 2001
-- We are your Lexus suspension experts--
BCR - KW - PENSKE - OHLINS - HKS - GREDDY - STANCEPARTS
Links - Arms - SuperPro Poly Bushings - Solid Bearing Conversions - Motor Mounts
RB BBK's and 2P Rotors, G-Loc pads, Radium Fuel Systems
Custom Fabrication Design and Machining - Industrial 3D Printing - Laser Cutting
2018 USTCC Sportsman Class Champions - 2018 NASA ST5 National Champions
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#10
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The knock issue is usually the upper bushing compression. The center crush tube is just a hair too short for the amount of torque you can put on the nut. So an impact driver (not impact wrench) but something with a much lower torque limit is required to get the stack to compress into the tube. The second thing that sometimes happens is the circlip on the shaft sometimes rolls over which prevent the stack from compressing as well. BC''s are still the best bang for the buck and can be very reliable if this issue is resolved. I think most of the time when people change the spring cartridge, they are reassembling the shock, so it has a tendency to resolve itself just from the re-compression of the bushing.
We just received the Ohlins R&T setup that we have been working on for the past 3 1/2 years Friday. This includes spring rates appropriate for the F as well as new valving. Testing this coming week and might get out the the track on Friday.
We just received the Ohlins R&T setup that we have been working on for the past 3 1/2 years Friday. This includes spring rates appropriate for the F as well as new valving. Testing this coming week and might get out the the track on Friday.
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#11
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The knock issue is usually the upper bushing compression. The center crush tube is just a hair too short for the amount of torque you can put on the nut. So an impact driver (not impact wrench) but something with a much lower torque limit is required to get the stack to compress into the tube. The second thing that sometimes happens is the circlip on the shaft sometimes rolls over which prevent the stack from compressing as well. BC''s are still the best bang for the buck and can be very reliable if this issue is resolved. I think most of the time when people change the spring cartridge, they are reassembling the shock, so it has a tendency to resolve itself just from the re-compression of the bushing.
We just received the Ohlins R&T setup that we have been working on for the past 3 1/2 years Friday. This includes spring rates appropriate for the F as well as new valving. Testing this coming week and might get out the the track on Friday.
We just received the Ohlins R&T setup that we have been working on for the past 3 1/2 years Friday. This includes spring rates appropriate for the F as well as new valving. Testing this coming week and might get out the the track on Friday.
The only thing I can suggest at this point is if you can create a video showing step by step what you want me to do so there is absolutely no way I'm missing a thing. It would be greatly appreciated.
Last edited by Compthis; 08-31-14 at 11:07 AM.
#12
#13
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If all the parts were designed and built with the right tolerances, there should be no issue. The fact that I'm having this issue with two corners is a testament to an inferior product. The only thing I'm getting out of the buck I spent is the bang. In my case, their suspension has a 50% failure rate. I had the suspension professionally installed by Defcon Racing who did every other modification to my car flawlessly. Days later, I brought the car to suspension expert Scott Murfin at http://www.canalignment.com/ who is the chief instructor for the Ontario Time Attack series where he made his adjustments to the suspension and aligned my F to make sure I didn't cut corners. That visit cost me $400 alone. I've emailed you regarding the issue numerous times, your customer service is great, no complaint there. You've offered me trouble shooting tips but nothing has worked. This suspension failed before a year of use and what's worse, the car was stored for 5 months of the year. So within 6 months of road use I'm left holding the empty bag. Ultimately it's my fault for buying a cheap product, you get what you pay for.......I've tried everything you told me through email and even what you just posted. Nothing works.....
The only thing I can suggest at this point is if you can create a video showing step by step what you want me to do so there is absolutely no way I'm missing a thing. It would be greatly appreciated.
The only thing I can suggest at this point is if you can create a video showing step by step what you want me to do so there is absolutely no way I'm missing a thing. It would be greatly appreciated.
as with any part, labor and setup are so far out of the scale of the original product in cost that if you are going to go to these lengths, you likely should invest more in the shocks anyway. I deliver alignment specs that any shop should be able to hit and really beyond that is a few damping settings that you set to your preference and ride height. If you are going to do a serious setup, you want more adjustment in your shocks anyway, at least divorced compression and rebound adjustment. So my advice to anyone on a budget is just consult with me first on setup targets and I will get you very close. In most cases hiring a high profile or high end shop really will not get you much further than piece of mind as there are just not that many settings to tinker with, likely even less from a professionals perspective so you might both be frustrated for no reason..
Mike
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Redefining Lexus Aftermarket Parts Since 2001
-- We are your Lexus suspension experts--
BCR - KW - PENSKE - OHLINS - HKS - GREDDY - STANCEPARTS
Links - Arms - SuperPro Poly Bushings - Solid Bearing Conversions - Motor Mounts
RB BBK's and 2P Rotors, G-Loc pads, Radium Fuel Systems
Custom Fabrication Design and Machining - Industrial 3D Printing - Laser Cutting
2018 USTCC Sportsman Class Champions - 2018 NASA ST5 National Champions
Redefining Lexus Aftermarket Parts Since 2001
-- We are your Lexus suspension experts--
BCR - KW - PENSKE - OHLINS - HKS - GREDDY - STANCEPARTS
Links - Arms - SuperPro Poly Bushings - Solid Bearing Conversions - Motor Mounts
RB BBK's and 2P Rotors, G-Loc pads, Radium Fuel Systems
Custom Fabrication Design and Machining - Industrial 3D Printing - Laser Cutting
2018 USTCC Sportsman Class Champions - 2018 NASA ST5 National Champions
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#14
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Thanks for your response, I appreciate you spear heading this. I just want to include a picture I took today to also show how much of the adjustment collar I'm using. With the car sitting as high as it is, and running 16k fronts, premature wear on the damper should not be an issue. With the factory wheel on factory spec tires sitting on the ground, the floor to fender measurement is 26-5/8". So that's no where close to "slammed" as one may say.
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Last edited by Compthis; 08-31-14 at 06:49 PM.
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