Gentlemen,
I've been daily driving the car in its current form (post swap etc) for ~4 years.

A few days ago my clutch pedal started feeling soft (this is the clutch I have with the ITR motor & tranny). The best way to describe the feeling is like if I was starting the car in 2nd gear (of course, I was in 1st gear). I checked the fluid, it was good. Since the master and slave cylinders are cheap ($33 shipped - Dorman Lifetime Warranty) and since it had been a while since I last bled the system, I decided to go heavy handed and proceeded to swap both. I then put ATE DOT4 Blue fluid and bled it again.

No change: pedal is still softer than usual, car feels like it's in a higher gear while taking off (engine wants to bog down) even if I am in 1st gear.

Since I had a fork snap back in my DSM days (ACT 2700lbs), I had this one reinforced at the same time the car was getting swapped a few years ago, so I doubt the fork is damaged or bent. Here's a picture of it:



Any input on what you think might have happened will be greatly appreciated. I am fearing a pressure plate issue, but I sure hope that's not the case.

Cheers!

 

Update: 90% sure it's the clutch.

Went for a spin and floored her in 1st and 2nd, seems to hold 1st gear without issues all the way to redline, but started slipping as soon as we put 2nd gear.

 

Wow.....thats a bit excessive. Never had a fork snap in two on a Honda, or heard. But its cool that you made safety procedures. I just hope the additional weight shouldn't effect the hydraulic setup.

 

As you mentioned, this is a clutch issue. Was the clutch pedal height properly adjusted?

 

There's a misconception that a slipping clutch means that you should bleed the system and get new cylinders. This is false.

Master and slave cylinders only serve to DISengage the clutch. Fluid bleeding, and cylinders do not help to engage the clutch. It is mechanically engaged via springs. The fork also ONLY serves to disengage the clutch. A reinforced fork cannot make a clutch feel harder or grip better.

Nomenclature:
-DISengaged: disk is disconnected from driveline. (Happens when you push the pedal DOWN and everything is working properly). Fluid provides force to DISengage the clutch.

-Engaged: disk is connecting the driveline to the engine. (Pedal UP, everything working properly).

If you removed all the fluid and both cylinders from the car and threw them into the depths of the ocean, the clutch would forever be doomed to be fully engaged via the clutch springs in the pressure plate. But they'd throw you in fish jail for life for polluting the ocean.

If your clutch is slipping, the only way the hydraulic components could be the culprits is if they are mal-adjusted. If there is no freeplay in your clutch pedal, the master cylinder is always slightly pushing on the clutch and disengaging it.

Adjust your freeplay first.

If that doesn't work...you have a slipping clutch.

The fact that your clutch feels softer than usual probably means the springs are no longer pressing on the disk hard enough to let it grip.

Does the clutch feel soft compared to what it usually feels like? Or are you comparing it to a DSM clutch? Honda hydraulic clutches feel soft. Its awesome.

Also worth noting....a brand new clutch will feel softer than a broken in clutch...generally speaking.

 

Thanks for the input, all.

I had a fork snap before, it's terrible. Didn't want to take chances.

Due to issues with the pedal bushings/spring (way too much play), I adjusted the pedal all the way up. I already have a new set of OEM bushings/spring to rebuild the pedal mounting mechanism.

Yes, I agree with the above, the only reason I went heavy handed and swapped both MC and SC was because the pedal felt different, clutch was engaging in a weird way, they were cheap enough and I wanted to exclude components and get to the culprit as fast as possible. The slipping was noted after the MC and SC were changed, on a test drive the following day.

Agreed. And since I have the pedal backed all the way up (tons of freeplay), I excluded hydraulic components from the equation and wrote my update earlier this morning: "90% sure it's the clutch"

The clutch feels softer than what it normally felt. I couldn't possibly compare it to the DSM clutch, which had a 2700lbs pressure plate. This one is like 1600 or something.

 

Well...your clutch might be fine.

RonJeremy@Ht and I go back and forth about this. But pedal height and freeplay can be set independently.

Set your freeplay so you have a half inch or so. Then see if the clutch still slips.

 

Quick Update:





Like they say... a picture is worth 1000 posts.

Hope it helps someone. Thanks for chiming in, all.

 

What clutch and pressure plate combo is that? Did you mix and match them by chance?

 

ACT AI4-HDSS. Original and complete clutch kit, straight from ACT.
I must say that clutch had about 50k miles of daily driving and just a handful of very gentle launches. I think it held up pretty well, just surprised the pressure plate failed that way. I'd never seen that.

 

So did you purchase this clutch yourself or did it come with the car? Unnecessary quick shifts, by dropping the clutch and gunning it, might have cause the clutch itself to have worn out.

 

I bought the clutch in 2011 (when I did the swap) and put all the miles on her myself. She's never been abused.
Even the very few times I've launched her, it was relatively low rpm and gentle disengaging.

 

My only conclusion is that

A) the soft line that is ran long with the clutch line is expanding or worn out
B) that clutch is already going.