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Clutch is slipping when shifting at redline... New clutch?

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Clutch is slipping when shifting at redline... New clutch?

 
Old 05-30-2013, 05:00 AM
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This has been discussed many times over the years - the issue is the pressure plate is too weak to hold the flywheel and friction disc together at high rpm. Honda in 2004 put a much heavier flywheel in the car, among other changes. Many people think the CDV removal fixes the slip, but removing the CDV doesn't fix the issue since it is really the PP that is causing the slip.

The easy way to tell if the clutch is slipping is to do the lug test. If the clutch grips fine and only exhibits slip at the redline shifts, then it is the natural behavior of the current PP and flywheel combination. I bet you that if you pop the clutch on a 2-3 shift at 5k rpm, there will be zero slip, but if you do it at 8k rpm, there will be slip because of the grip threshold of the current PP.

The fix generally is to either put in a lighter flywheel (AP1) or a stronger PP (ACT PP), or both. Removing the CDV will make the shifts feel more direct.

Either:
- shift slower, you'll be just as fast and not damage the car
- replace the pp with a firmer one
- replace the flywheel with a lighter one
- replace the flywheel and pp

Remove the CDV with one of these and the car will feel more "direct", but I'd recommend you change the clutch system before you bother with the CDV.
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Old 05-30-2013, 05:22 AM
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Originally Posted by Saki GT View Post
This has been discussed many times over the years - the issue is the pressure plate is too weak to hold the flywheel and friction disc together at high rpm. Honda in 2004 put a much heavier flywheel in the car, among other changes. Many people think the CDV removal fixes the slip, but removing the CDV doesn't fix the issue since it is really the PP that is causing the slip.

The easy way to tell if the clutch is slipping is to do the lug test. If the clutch grips fine and only exhibits slip at the redline shifts, then it is the natural behavior of the current PP and flywheel combination. I bet you that if you pop the clutch on a 2-3 shift at 5k rpm, there will be zero slip, but if you do it at 8k rpm, there will be slip because of the grip threshold of the current PP.

The fix generally is to either put in a lighter flywheel (AP1) or a stronger PP (ACT PP), or both. Removing the CDV will make the shifts feel more direct.

Either:
- shift slower, you'll be just as fast and not damage the car
- replace the pp with a firmer one
- replace the flywheel with a lighter one
- replace the flywheel and pp

Remove the CDV with one of these and the car will feel more "direct", but I'd recommend you change the clutch system before you bother with the CDV.


He is 100% correct about this issue and the solution.
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Old 05-30-2013, 04:14 PM
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Originally Posted by Saki GT View Post
This has been discussed many times over the years - the issue is the pressure plate is too weak to hold the flywheel and friction disc together at high rpm. Honda in 2004 put a much heavier flywheel in the car, among other changes. Many people think the CDV removal fixes the slip, but removing the CDV doesn't fix the issue since it is really the PP that is causing the slip.

The easy way to tell if the clutch is slipping is to do the lug test. If the clutch grips fine and only exhibits slip at the redline shifts, then it is the natural behavior of the current PP and flywheel combination. I bet you that if you pop the clutch on a 2-3 shift at 5k rpm, there will be zero slip, but if you do it at 8k rpm, there will be slip because of the grip threshold of the current PP.

The fix generally is to either put in a lighter flywheel (AP1) or a stronger PP (ACT PP), or both. Removing the CDV will make the shifts feel more direct.

Either:
- shift slower, you'll be just as fast and not damage the car
- replace the pp with a firmer one
- replace the flywheel with a lighter one
- replace the flywheel and pp

Remove the CDV with one of these and the car will feel more "direct", but I'd recommend you change the clutch system before you bother with the CDV.
EXACTLY the symptoms i have

shifting at 5k is perfect, nothing slips but at 8k it slips!

lets say i want to fix the problem, and not shift slower,

should i might as well replace the clutch, the PP, and Flywheel at the same time because the tranny is out of the car?
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Old 05-31-2013, 01:38 AM
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If it slips it slips point blank. U need to replace the clutch. Don't waste time with aftermarket cuz the OEM is better than that. If u burned the flywheel u need to replace with a new OEM one and they cannot be resurfaced. Buy a clutch kit from Orielys which is made by Sachs which is good stuff and has lifetime warranty. Replace flywheel from a dealer ordered one and u will be back in business.
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Old 05-31-2013, 04:40 AM
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Originally Posted by Seven11 View Post
lets say i want to fix the problem, and not shift slower,

should i might as well replace the clutch, the PP, and Flywheel at the same time because the tranny is out of the car?
I'm the kind of person who'd prefer to pull everything apart once, and I don't have the time to inspect and then order parts, so I'd put all new parts in at the same time, including the throwout bearing and friction disc.

- OEM AP1 flywheel - about 10 pounds lighter than AP2, it will make the engine feel "lighter" and rpm will change quicker
- ACT PP - about twice the grip of OEM, it will bite harder
- Remove CDV - suppresses driveline shock by regulating engagement speed, removing it will speed the clutch engagement

I personally plan to replace my OEM with an AP1 flywheel and ACT PP when it wears out. This seems to be the fix that most people like when staying stock overall with the car. Once I make that chance, I'll decide if I want to remove the CDV.

Side note - you can replace an AP2 clutch slave cylinder with an AP1 unit that does not have the CDV in it, or pull the CDV out of your AP2 unit. If you buy and swap the AP1 unit in, you can go back and forth and test the difference.
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Old 05-31-2013, 03:53 PM
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Originally Posted by Saki GT View Post
Originally Posted by Seven11' timestamp='1369959266' post='22577118
lets say i want to fix the problem, and not shift slower,

should i might as well replace the clutch, the PP, and Flywheel at the same time because the tranny is out of the car?
I'm the kind of person who'd prefer to pull everything apart once, and I don't have the time to inspect and then order parts, so I'd put all new parts in at the same time, including the throwout bearing and friction disc.

- OEM AP1 flywheel - about 10 pounds lighter than AP2, it will make the engine feel "lighter" and rpm will change quicker
- ACT PP - about twice the grip of OEM, it will bite harder
- Remove CDV - suppresses driveline shock by regulating engagement speed, removing it will speed the clutch engagement

I personally plan to replace my OEM with an AP1 flywheel and ACT PP when it wears out. This seems to be the fix that most people like when staying stock overall with the car. Once I make that chance, I'll decide if I want to remove the CDV.

Side note - you can replace an AP2 clutch slave cylinder with an AP1 unit that does not have the CDV in it, or pull the CDV out of your AP2 unit. If you buy and swap the AP1 unit in, you can go back and forth and test the difference.

cool, thanks a lot

i guess i will be changing the a bunch of components
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Old 05-31-2013, 04:10 PM
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yeah, the clutch in my 09 is retarded. i have been driving manual tranny cars for over 20 years. this is ridiculous. to say that a 2-3 and 3-4 good shift at redline results in multi second slippage to the next redline is "designed in" or "normal" is just plain bonkers and a TERRIBLE engineering solution. soon i will have to bite the bullet with a stronger pressure plate. at the same time i will get an AP1 flywheel. the current setup is just plain almost un-driveable for me in a 'fun' manner as the shifts are simply horrible. love everything else about the car, but when i first drive it with 1900 miles on it i thought that someone had smoked the clutch and sold the car to me. never would i have guessed honda re designed the AP2 to be driven by my now dead grandmother. oh well. it'll get there
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Old 06-01-2013, 05:15 PM
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i dont know what happened

but for the past couple days, i was able to shift at full redline with only a little bit of slip of the clutch

felt like everything gripped but the Clutch Delay Valve let it slip just a bit
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Old 06-01-2013, 08:18 PM
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Originally Posted by Seven11 View Post
i dont know what happened

but for the past couple days, i was able to shift at full redline with only a little bit of slip of the clutch

felt like everything gripped but the Clutch Delay Valve let it slip just a bit
i guess you learned to drive the car like rob-2 was trying to tell you LOL jk. i've experienced that as well. some days it wont happen and others it will. it all depends how quickly you slam through the gears like everyone was saying.
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Old 06-02-2013, 12:47 AM
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Originally Posted by icantbeseen1 View Post
Originally Posted by Seven11' timestamp='1370135734' post='22580946
i dont know what happened

but for the past couple days, i was able to shift at full redline with only a little bit of slip of the clutch

felt like everything gripped but the Clutch Delay Valve let it slip just a bit
i guess you learned to drive the car like rob-2 was trying to tell you LOL jk. i've experienced that as well. some days it wont happen and others it will. it all depends how quickly you slam through the gears like everyone was saying.
yuuuup, just learned how to drive... within the past couple days. Even though i was driving a manual car since i was 16 (i am 28 now)

you're right, drove after filling up a full tank and tried to shift quick and the clutch slipped bad.
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