Clutch problem?
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 859
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Clutch problem?
This is in regards to my pop's zo6. He has a RPS Twin Carbon Clutch. Recently, he's been having a few problems that we believe to be clutch related, just looking for opinions before we tear it down. The clutch pedal sometimes sticks to the floor and it won't return. When coming to a stop and down shifting, it makes a loud clack when coming to stop. When in first gear, with the clutch all the way in, the car starts to move. When sitting still, he can't put car in reverse, has to kill motor and put it in reverse and then start it. He said he can shift better without the clutch than with. Is there an adjustment possibly?
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has it always acted this way since the install?... it sounds to me like the clutch might have worn down a tad bit and the slave will not engage the pressure plate far enough to release it from the discs, that would explain it creeping forward while in gear even with the clutch pedal depressed and making it difficult to shift into reverse... I am not familiar with how the rps clutches are designed but my act twin has shims on the pressure plate studs that can be used for adjustment as the discs wear down so that could be a possible fix or you might even look into a tick master cylinder
Instructor
Joined: Jan 2011
Posts: 176
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From: Buffalo Grove Illinois
I had same issues exactly. My master cylinder wasnt working correctly. It would not fully disengage the clutch, hence the car moving with clutch all the way down. The pedal stuck to the floor frequently too until I pulled the pedal up with my toe. I started to have these issues after I had a twin-disc clutch installed. I installed a Tick master and all those issues went away.
Replace the master. It is a pretty easy job and no tear down of the drivetrain needed. I would bet that this is your issue.
Replace the master. It is a pretty easy job and no tear down of the drivetrain needed. I would bet that this is your issue.
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 859
Likes: 1
Clutch problem?
Originally Posted by TwinTurboZ51
I had same issues exactly. My master cylinder wasnt working correctly. It would not fully disengage the clutch, hence the car moving with clutch all the way down. The pedal stuck to the floor frequently too until I pulled the pedal up with my toe. I started to have these issues after I had a twin-disc clutch installed. I installed a Tick master and all those issues went away.
Replace the master. It is a pretty easy job and no tear down of the drivetrain needed. I would bet that this is your issue.
Replace the master. It is a pretty easy job and no tear down of the drivetrain needed. I would bet that this is your issue.
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Just an FYI to prepare your dad for the increase in pedal pressure. Personally, I would say it was about a 25 to 30% (~) increase. Now that I've become so accustomed to it, I don't even notice it any longer. On the BIG plus side, NO pedal-sticking-to-the-floor syndrome whatsoever.
HTH
Btw, yes I also have an aftermarket twin-disc clutch, but it's a McLeod RST however.
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tick offers a stock bore master that won't increase pedal pressure from what it already is
Pro
Joined: May 2012
Posts: 666
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From: Milwaukee WI
there is a 13/16 and 7/8" tilton, which is what you want if you want something good. The 13/16 only moves a tiny bit more fluid than stock though, and its slightly more pressure. Tick sells the 7/8" only i thought?
The 7/8" is super noticeable at first but you get used to it in a couple weeks. I feel like its easier to control then stock now that I am used to it. It is heavy but its not unmanageable for a normal sized adult male.
The 7/8" is super noticeable at first but you get used to it in a couple weeks. I feel like its easier to control then stock now that I am used to it. It is heavy but its not unmanageable for a normal sized adult male.
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From: Anthony TX
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St. Jude Donor '08
The very first thing that I would try is a good clutch system bleed. If there is any air at all in the system, it will do the same thing. If you are POSITIVE that bleeding will not correct the issue, YES,,, Replace the MASTER CYL!
Once you do that, MAKE SURE its properly bleed.
IF, you go the TICK Master Cyl replacement route, You will have to learn how to properly adjust the clutch peddle adjustment rod.
Improper adjustment and you risk having the same issues your having now. Too much rod and you will have constant pressure on the pressure plate springs and clutch slippage under power.
If you have excessive peddle rod length you also risk over compression of the pressure plate springs and pressure plate spring damage.
See what a good bleed does for you. Do you have a remote bleeder??
Bill
Once you do that, MAKE SURE its properly bleed.
IF, you go the TICK Master Cyl replacement route, You will have to learn how to properly adjust the clutch peddle adjustment rod.
Improper adjustment and you risk having the same issues your having now. Too much rod and you will have constant pressure on the pressure plate springs and clutch slippage under power.
If you have excessive peddle rod length you also risk over compression of the pressure plate springs and pressure plate spring damage.
See what a good bleed does for you. Do you have a remote bleeder??
Bill
Last edited by Bill Curlee; Aug 3, 2015 at 04:00 PM.
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 859
Likes: 1
Clutch problem?
Originally Posted by Bill Curlee
The very first thing that I would try is a good clutch system bleed. If there is any air at all in the system, it will do the same thing. If you are POSITIVE that bleeding will not correct the issue, YES,,, Replace the MASTER CYL!
Once you do that, MAKE SURE its properly bleed.
IF, you go the TICK Master Cyl replacement route, You will have to learn how to properly adjust the clutch peddle adjustment rod.
Improper adjustment and you risk having the same issues your having now. Too much rod and you will have constant pressure on the pressure plate springs and clutch slippage under power.
If you have excessive peddle rod length you also risk over compression of the pressure plate springs and pressure plate spring damage.
See what a good bleed does for you. Do you have a remote bleeder??
Bill
Once you do that, MAKE SURE its properly bleed.
IF, you go the TICK Master Cyl replacement route, You will have to learn how to properly adjust the clutch peddle adjustment rod.
Improper adjustment and you risk having the same issues your having now. Too much rod and you will have constant pressure on the pressure plate springs and clutch slippage under power.
If you have excessive peddle rod length you also risk over compression of the pressure plate springs and pressure plate spring damage.
See what a good bleed does for you. Do you have a remote bleeder??
Bill
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 859
Likes: 1
Clutch problem?
Just wanted to thank everyone for your help. We bled it and it didn't help, so we put in a new clutch master cylinder and all is well now. Again, huge thanks to you guys because we would have dropped the entire drivetrain thinking it was the clutch
Melting Slicks
Joined: Jun 2005
Posts: 2,396
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From: Sicamous BC
Having owned a RPS street lite twin carbon, it will not full release with stock hydraulics. My fix was a McLeod MC, it is a slightly larger bore than the stock MC so only a slight increase in pedal which is already brutal with the RPS clutch.
I fought the release issue, they claimed it would work with stock hyd's......it will not. I tried shimming it, had it in & out several times, sent it back to them twice. In the end the pedal pressure was to much for my style.....& the attitude of the company owner
I fought the release issue, they claimed it would work with stock hyd's......it will not. I tried shimming it, had it in & out several times, sent it back to them twice. In the end the pedal pressure was to much for my style.....& the attitude of the company owner