bradesp
08-04-2014, 09:27 PM
Guys,
I've been hoping to "emerge" locally with a killer ride, but dang if I'm not vexed...
After acquiring my first ever Miata 2000' in Sept 2012 and investing serious $$$ in suspension / performance mods I still have an unacceptable shimmy when I drive the car... randomly below 60, and consistently above 60 with severity ranging from light to moderate.
I had Glenn at Long Road Racing do some of my early work, but when I reached out to him today, he informed me he's no longer doing direct customer maintenance :-)
So, who do you know that is a NINJA at diagnosing the root cause of driveline / vibration / shimmy issues? PLEASE HELP!
Below are the details of my setup / frustration!
Bradesp
Details of my 2000' LS
I know too well that some Miata owners NEVER experience a shimmy, while others have a constant shimmy at certain speeds (32mph and 65mph being the most common). Despite doing all the "recommended things" my shimmy just doesn't want to go away
Emilio from 949 racing suggested I find a driveline technician that truly understands driveline setups, suspension, geometry, and most importantly, is skilled at knowing what components to isolate and test for possible source of chassis shim.
Advice I got from 949 Racing in California (the manuf of the wheels on my Miata):
Remove each wheel. Do not remove balance weights. Install on wheel balance then rotate by hand. Measure runout (wobble) both vertical and horizontal. Measure both tire and wheel. Spec for the wheel is .020 runout. You will not notice vibration until about .080" runout. We recommend replacing any wheel or tire past .120"
If wheels check out OK, put car on hoist. Start, put in top gear and accelerate to speedometer reading that matches your vibration on the road.
Here's What I've Done So Far:
Flyin Miata X-Brace Installed
Custom Tuned Coil-Overs Installed - FatCat
Flyin Miata Front Sway Bar Installed
Installed NEW Racing Beat Adjustable Sway Bar END LINKS
OEM Rear Sway Bar Removed - Recommended by FatCat based on custom Coil-Over setup
Ride Height Adjusted Per Coil-Over Manuf Specs
Corner Balance Adjustment Performed
Alignment - done AFTER coil-over installation and ride-height adjustment
Install new Miata Performance Tie-Rod Links
Installed lightly used control arms
Installed lightly used lower ball joints
Installed new drive shaft and U-Joint
New MIata Race Wheels Installed - 949 Race Wheels -6UL
New Tires Installed - RoadForce Balanced 3x at two different locations to achieve sub 10lb #'s... Unfortunately two wheels are NOT below 10lbs. Some other MIata owners claim that anything over 10lbs of road force (using the Hunter 9700) will induce shimmy on a Miata
I've been hoping to "emerge" locally with a killer ride, but dang if I'm not vexed...
After acquiring my first ever Miata 2000' in Sept 2012 and investing serious $$$ in suspension / performance mods I still have an unacceptable shimmy when I drive the car... randomly below 60, and consistently above 60 with severity ranging from light to moderate.
I had Glenn at Long Road Racing do some of my early work, but when I reached out to him today, he informed me he's no longer doing direct customer maintenance :-)
So, who do you know that is a NINJA at diagnosing the root cause of driveline / vibration / shimmy issues? PLEASE HELP!
Below are the details of my setup / frustration!
Bradesp
Details of my 2000' LS
I know too well that some Miata owners NEVER experience a shimmy, while others have a constant shimmy at certain speeds (32mph and 65mph being the most common). Despite doing all the "recommended things" my shimmy just doesn't want to go away
Emilio from 949 racing suggested I find a driveline technician that truly understands driveline setups, suspension, geometry, and most importantly, is skilled at knowing what components to isolate and test for possible source of chassis shim.
Advice I got from 949 Racing in California (the manuf of the wheels on my Miata):
Remove each wheel. Do not remove balance weights. Install on wheel balance then rotate by hand. Measure runout (wobble) both vertical and horizontal. Measure both tire and wheel. Spec for the wheel is .020 runout. You will not notice vibration until about .080" runout. We recommend replacing any wheel or tire past .120"
If wheels check out OK, put car on hoist. Start, put in top gear and accelerate to speedometer reading that matches your vibration on the road.
Here's What I've Done So Far:
Flyin Miata X-Brace Installed
Custom Tuned Coil-Overs Installed - FatCat
Flyin Miata Front Sway Bar Installed
Installed NEW Racing Beat Adjustable Sway Bar END LINKS
OEM Rear Sway Bar Removed - Recommended by FatCat based on custom Coil-Over setup
Ride Height Adjusted Per Coil-Over Manuf Specs
Corner Balance Adjustment Performed
Alignment - done AFTER coil-over installation and ride-height adjustment
Install new Miata Performance Tie-Rod Links
Installed lightly used control arms
Installed lightly used lower ball joints
Installed new drive shaft and U-Joint
New MIata Race Wheels Installed - 949 Race Wheels -6UL
New Tires Installed - RoadForce Balanced 3x at two different locations to achieve sub 10lb #'s... Unfortunately two wheels are NOT below 10lbs. Some other MIata owners claim that anything over 10lbs of road force (using the Hunter 9700) will induce shimmy on a Miata