Very strange front end shake and wobble....
11-10-04, 11:20 AM
#31
EV ftw!!!
Thread Starter
Originally posted by rominl
same here, and it has to be heavy rain. my theory is that's how you can get enough water in that channel
same here, and it has to be heavy rain. my theory is that's how you can get enough water in that channel
11-10-04, 12:19 PM
#32
Lexus Fanatic
iTrader: (20)
Hameed you can just switch to the 997 when it rains in the future. You know that bad boy handles great in the rain with no balance problems. 
11-10-04, 12:39 PM
#33
EV ftw!!!
Thread Starter
Originally posted by bitkahuna
Hameed you can just switch to the 997 when it rains in the future. You know that bad boy handles great in the rain with no balance problems.
Hameed you can just switch to the 997 when it rains in the future. You know that bad boy handles great in the rain with no balance problems.
11-10-04, 10:02 PM
#34
Originally posted by bitkahuna
Hameed you can just switch to the 997 when it rains in the future. You know that bad boy handles great in the rain with no balance problems.
Hameed you can just switch to the 997 when it rains in the future. You know that bad boy handles great in the rain with no balance problems.
11-12-04, 03:02 PM
#36
Pole Position
Originally posted by rominl
haha that's not a bad idea at all indeed! time to talk to my wife about getting another car for the rain now
haha that's not a bad idea at all indeed! time to talk to my wife about getting another car for the rain now
11-12-04, 11:30 PM
#38
Lexus Champion
That was quite a detailed response from the Professor character... the bottom line is, when I worked at HRE, we became aware of this problem some time after beginning to sell the reverse-drop center wheels. A customer in Miami called to complain about a vibration in the rain. After some head scratching and testing, we decided the customer was, in fact, right.
The "drop center" region of the wheel is necessary to physically mount the tires on all wheels. The "water retention issue" is only present on so-called "reverse drop center wheels", aka 'flat style lip.'
With a "Conventional" or "standard" profile rim, the drop center is located towards the 'face' or front of the wheel. Due to this configuration, no channel exists for water to accumulate in. N o issue possible here!
For styling reasons, the "reverse" style rims are currently very popular. To achieve this large 'full face' wheel spoke style, the "center" (plate that comprises the wheel spokes) portion is basically the full diameter of the wheel. This necessitates moving the drop center region of the wheel to the rear, or inside of the wheels. Unfortunately, this creates a channel that can collect water or other liquids directly behind the wheel assembly nuts.
With small amounts of liquids, or large amounts at low speed, the vibration does not manifest itself. Since no wheel is PERFECTLY round, larger amounts of water will tend to migrate towards a high spot (actually a depression if you could see it from the liquid's point of view) where it essentially gets stuck as centrifugal force builds. This acts like a giant wheel weight, and throws the wheel/tire assemble out of balance.
HRE's engineer and I did exhaustive testing and brainstorming in attempt to solve this issue. We created spiral 'dams' made of clay in hopes of directing water out of the channel and the wheel- tests proved the water would simply pass right over the dam, and in some cases even exxagerated the problem by trapping the water between the dams.
We toyed with closed-cell foam inserts, but this created other issues. Increasing the size of the drop-center region (to decrease the channels' width) would work well, but makes it all but impossible to assemble the wheels...
OZ has a neat solution to this on their Superlegerra 3 wheels, but it is patented and (frankly) makes the wheels quite heavy (18x10 weighs 26 lbs... my 20x10.5 HREs weigh 27 lbs!). Also, it requires a blind fastener which can strip or create issues if the wheel ever needed to be serviced... as you can see, besides the patent infringement issues, there are valid technical issues with this compromise.
Basically, most (if not all) of the three-piece Japanese and American-made reverse drop center wheels will have this issue if enough water is present. Most people will live with it because they love the 'look' this style of rim provides. So, there is the age-old question- do you warn every single potential customer and put yourself out of business in the process? Or do you simply suggest that the customer move to a more arid climate once an issue occurs?
No easy answers here.... my suggestion: if you have a sweet set of aftermarket wheels, spend $10 on an Absorber, and keep it in the trunk!
Best regards,
Bob Hale
Director of Marketing
Zone Wheels USA
The "drop center" region of the wheel is necessary to physically mount the tires on all wheels. The "water retention issue" is only present on so-called "reverse drop center wheels", aka 'flat style lip.'
With a "Conventional" or "standard" profile rim, the drop center is located towards the 'face' or front of the wheel. Due to this configuration, no channel exists for water to accumulate in. N o issue possible here!
For styling reasons, the "reverse" style rims are currently very popular. To achieve this large 'full face' wheel spoke style, the "center" (plate that comprises the wheel spokes) portion is basically the full diameter of the wheel. This necessitates moving the drop center region of the wheel to the rear, or inside of the wheels. Unfortunately, this creates a channel that can collect water or other liquids directly behind the wheel assembly nuts.
With small amounts of liquids, or large amounts at low speed, the vibration does not manifest itself. Since no wheel is PERFECTLY round, larger amounts of water will tend to migrate towards a high spot (actually a depression if you could see it from the liquid's point of view) where it essentially gets stuck as centrifugal force builds. This acts like a giant wheel weight, and throws the wheel/tire assemble out of balance.
HRE's engineer and I did exhaustive testing and brainstorming in attempt to solve this issue. We created spiral 'dams' made of clay in hopes of directing water out of the channel and the wheel- tests proved the water would simply pass right over the dam, and in some cases even exxagerated the problem by trapping the water between the dams.
We toyed with closed-cell foam inserts, but this created other issues. Increasing the size of the drop-center region (to decrease the channels' width) would work well, but makes it all but impossible to assemble the wheels...
OZ has a neat solution to this on their Superlegerra 3 wheels, but it is patented and (frankly) makes the wheels quite heavy (18x10 weighs 26 lbs... my 20x10.5 HREs weigh 27 lbs!). Also, it requires a blind fastener which can strip or create issues if the wheel ever needed to be serviced... as you can see, besides the patent infringement issues, there are valid technical issues with this compromise.
Basically, most (if not all) of the three-piece Japanese and American-made reverse drop center wheels will have this issue if enough water is present. Most people will live with it because they love the 'look' this style of rim provides. So, there is the age-old question- do you warn every single potential customer and put yourself out of business in the process? Or do you simply suggest that the customer move to a more arid climate once an issue occurs?
No easy answers here.... my suggestion: if you have a sweet set of aftermarket wheels, spend $10 on an Absorber, and keep it in the trunk!
Best regards,
Bob Hale
Director of Marketing
Zone Wheels USA
Last edited by SoCalSC4; 11-12-04 at 11:36 PM.
11-13-04, 06:53 AM
#39
Pole Position
Originally posted by SoCalSC4
OZ has a neat solution to this on their Superlegerra 3 wheels, but it is patented and (frankly) makes the wheels quite heavy (18x10 weighs 26 lbs... my 20x10.5 HREs weigh 27 lbs!). Also, it requires a blind fastener which can strip or create issues if the wheel ever needed to be serviced... as you can see, besides the patent infringement issues, there are valid technical issues with this compromise.
OZ has a neat solution to this on their Superlegerra 3 wheels, but it is patented and (frankly) makes the wheels quite heavy (18x10 weighs 26 lbs... my 20x10.5 HREs weigh 27 lbs!). Also, it requires a blind fastener which can strip or create issues if the wheel ever needed to be serviced... as you can see, besides the patent infringement issues, there are valid technical issues with this compromise.
Thanks for your "insider" feedback that validates that there is something strange happening and that there are solutions to the problem.
11-13-04, 11:59 AM
#40
wow thanks for the explanation professor! this is awesome info bob. so it basically helps to confirm and explains in details how the thing occurs and why. and i am glad to see that hre did put the effort in trying to find a solution for the problem. too bad it wasn't successful
but to be honest, at least just for me, i don't care much. firsrt of all it doesn't rain much here in cali (yay!), and even if i drive my car daily, it's all good. plus, when it shaked i sorta just keep my speed up or slow it down a little to eliminate the problem so it's not too bad
thanks again bob, your engineering insight is very very useful!
but to be honest, at least just for me, i don't care much. firsrt of all it doesn't rain much here in cali (yay!), and even if i drive my car daily, it's all good. plus, when it shaked i sorta just keep my speed up or slow it down a little to eliminate the problem so it's not too bad
thanks again bob, your engineering insight is very very useful!
12-07-04, 08:16 AM
#41
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wow, finally an answer from HRE's perspective. So after all this, i really wasn't crazy?
Originally posted by SoCalSC4
That was quite a detailed response from the Professor character... the bottom line is, when I worked at HRE, we became aware of this problem some time after beginning to sell the reverse-drop center wheels. A customer in Miami called to complain about a vibration in the rain. After some head scratching and testing, we decided the customer was, in fact, right.
The "drop center" region of the wheel is necessary to physically mount the tires on all wheels. The "water retention issue" is only present on so-called "reverse drop center wheels", aka 'flat style lip.'
With a "Conventional" or "standard" profile rim, the drop center is located towards the 'face' or front of the wheel. Due to this configuration, no channel exists for water to accumulate in. N o issue possible here!
For styling reasons, the "reverse" style rims are currently very popular. To achieve this large 'full face' wheel spoke style, the "center" (plate that comprises the wheel spokes) portion is basically the full diameter of the wheel. This necessitates moving the drop center region of the wheel to the rear, or inside of the wheels. Unfortunately, this creates a channel that can collect water or other liquids directly behind the wheel assembly nuts.
With small amounts of liquids, or large amounts at low speed, the vibration does not manifest itself. Since no wheel is PERFECTLY round, larger amounts of water will tend to migrate towards a high spot (actually a depression if you could see it from the liquid's point of view) where it essentially gets stuck as centrifugal force builds. This acts like a giant wheel weight, and throws the wheel/tire assemble out of balance.
HRE's engineer and I did exhaustive testing and brainstorming in attempt to solve this issue. We created spiral 'dams' made of clay in hopes of directing water out of the channel and the wheel- tests proved the water would simply pass right over the dam, and in some cases even exxagerated the problem by trapping the water between the dams.
We toyed with closed-cell foam inserts, but this created other issues. Increasing the size of the drop-center region (to decrease the channels' width) would work well, but makes it all but impossible to assemble the wheels...
OZ has a neat solution to this on their Superlegerra 3 wheels, but it is patented and (frankly) makes the wheels quite heavy (18x10 weighs 26 lbs... my 20x10.5 HREs weigh 27 lbs!). Also, it requires a blind fastener which can strip or create issues if the wheel ever needed to be serviced... as you can see, besides the patent infringement issues, there are valid technical issues with this compromise.
Basically, most (if not all) of the three-piece Japanese and American-made reverse drop center wheels will have this issue if enough water is present. Most people will live with it because they love the 'look' this style of rim provides. So, there is the age-old question- do you warn every single potential customer and put yourself out of business in the process? Or do you simply suggest that the customer move to a more arid climate once an issue occurs?
No easy answers here.... my suggestion: if you have a sweet set of aftermarket wheels, spend $10 on an Absorber, and keep it in the trunk!
Best regards,
Bob Hale
Director of Marketing
Zone Wheels USA
That was quite a detailed response from the Professor character... the bottom line is, when I worked at HRE, we became aware of this problem some time after beginning to sell the reverse-drop center wheels. A customer in Miami called to complain about a vibration in the rain. After some head scratching and testing, we decided the customer was, in fact, right.
The "drop center" region of the wheel is necessary to physically mount the tires on all wheels. The "water retention issue" is only present on so-called "reverse drop center wheels", aka 'flat style lip.'
With a "Conventional" or "standard" profile rim, the drop center is located towards the 'face' or front of the wheel. Due to this configuration, no channel exists for water to accumulate in. N o issue possible here!
For styling reasons, the "reverse" style rims are currently very popular. To achieve this large 'full face' wheel spoke style, the "center" (plate that comprises the wheel spokes) portion is basically the full diameter of the wheel. This necessitates moving the drop center region of the wheel to the rear, or inside of the wheels. Unfortunately, this creates a channel that can collect water or other liquids directly behind the wheel assembly nuts.
With small amounts of liquids, or large amounts at low speed, the vibration does not manifest itself. Since no wheel is PERFECTLY round, larger amounts of water will tend to migrate towards a high spot (actually a depression if you could see it from the liquid's point of view) where it essentially gets stuck as centrifugal force builds. This acts like a giant wheel weight, and throws the wheel/tire assemble out of balance.
HRE's engineer and I did exhaustive testing and brainstorming in attempt to solve this issue. We created spiral 'dams' made of clay in hopes of directing water out of the channel and the wheel- tests proved the water would simply pass right over the dam, and in some cases even exxagerated the problem by trapping the water between the dams.
We toyed with closed-cell foam inserts, but this created other issues. Increasing the size of the drop-center region (to decrease the channels' width) would work well, but makes it all but impossible to assemble the wheels...
OZ has a neat solution to this on their Superlegerra 3 wheels, but it is patented and (frankly) makes the wheels quite heavy (18x10 weighs 26 lbs... my 20x10.5 HREs weigh 27 lbs!). Also, it requires a blind fastener which can strip or create issues if the wheel ever needed to be serviced... as you can see, besides the patent infringement issues, there are valid technical issues with this compromise.
Basically, most (if not all) of the three-piece Japanese and American-made reverse drop center wheels will have this issue if enough water is present. Most people will live with it because they love the 'look' this style of rim provides. So, there is the age-old question- do you warn every single potential customer and put yourself out of business in the process? Or do you simply suggest that the customer move to a more arid climate once an issue occurs?
No easy answers here.... my suggestion: if you have a sweet set of aftermarket wheels, spend $10 on an Absorber, and keep it in the trunk!
Best regards,
Bob Hale
Director of Marketing
Zone Wheels USA
12-13-04, 06:39 AM
#43
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Join Date: Dec 2004
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shaking
the shaing that you are experiencing at certain high speeds is actually a common problem with the GS and is NOT related to 3 pc wheel designs. the shaking is sudden and pretty noticable and shakes the steering column too. the easiest way to sum up this problem is that it has to do with how the car reacts to the tires you are using (so it is a GS and a tire problem) in gerneal, tire with deeper tread designed for wet traction cause more violent shake.
i have alot of experience with this topic and here are some factors to consider based on tests:
GS OEM tires shakes a bit at 60mph but are the best choice for smooth operation (GY Invicta).
Continential Cont Extreme Contact tires will shake at both 60 and 75 mph--not violent, but noticable.
BF Goodrich Traction TAs will violentally shake at 75 and 80.
there is very little you can do to eliminate this weird occurence.
i have alot of experience with this topic and here are some factors to consider based on tests:
GS OEM tires shakes a bit at 60mph but are the best choice for smooth operation (GY Invicta).
Continential Cont Extreme Contact tires will shake at both 60 and 75 mph--not violent, but noticable.
BF Goodrich Traction TAs will violentally shake at 75 and 80.
there is very little you can do to eliminate this weird occurence.
12-13-04, 06:45 AM
#44
EV ftw!!!
Thread Starter
Re: shaking
Originally posted by steveslex
the shaing that you are experiencing at certain high speeds is actually a common problem with the GS and is NOT related to 3 pc wheel designs. the shaking is sudden and pretty noticable and shakes the steering column too. the easiest way to sum up this problem is that it has to do with how the car reacts to the tires you are using (so it is a GS and a tire problem) in gerneal, tire with deeper tread designed for wet traction cause more violent shake.
i have alot of experience with this topic and here are some factors to consider based on tests:
GS OEM tires shakes a bit at 60mph but are the best choice for smooth operation (GY Invicta).
Continential Cont Extreme Contact tires will shake at both 60 and 75 mph--not violent, but noticable.
BF Goodrich Traction TAs will violentally shake at 75 and 80.
there is very little you can do to eliminate this weird occurence.
the shaing that you are experiencing at certain high speeds is actually a common problem with the GS and is NOT related to 3 pc wheel designs. the shaking is sudden and pretty noticable and shakes the steering column too. the easiest way to sum up this problem is that it has to do with how the car reacts to the tires you are using (so it is a GS and a tire problem) in gerneal, tire with deeper tread designed for wet traction cause more violent shake.
i have alot of experience with this topic and here are some factors to consider based on tests:
GS OEM tires shakes a bit at 60mph but are the best choice for smooth operation (GY Invicta).
Continential Cont Extreme Contact tires will shake at both 60 and 75 mph--not violent, but noticable.
BF Goodrich Traction TAs will violentally shake at 75 and 80.
there is very little you can do to eliminate this weird occurence.
Last edited by Hameed; 12-13-04 at 06:46 AM.
12-13-04, 08:20 AM
#45
Forum Administrator
iTrader: (2)
Re: shaking
Originally posted by steveslex
the shaing that you are experiencing at certain high speeds is actually a common problem with the GS and is NOT related to 3 pc wheel designs. .
the shaing that you are experiencing at certain high speeds is actually a common problem with the GS and is NOT related to 3 pc wheel designs. .
The problem we're discussing here is totally different than the one you describe.... this one is based on water retention inside the rim due to wheel design and not the tires.
There are lots of threads about the GS wheel wobble at 60mph and other speeds if you care to search for them. This one, however is for a different reason
.