Flat shifting and a slipping clutch.

So I put my summer tires back on my car a few weeks back and last night the weather was fantastic, so I went out to a quiet stretch of freshly paved parkway to play around a bit.

I take my time shifting which is probably why I've never had some of the problems other members of the forums have had getting into 3rd gear under hard acceleration. This doesn't generally bother me because I don't normally care much about working through the gears really quickly. I try to get fully into gear fairly gently before I step on it, generally before a corner into 2nd and then getting on it after I've finished turning or down an on ramp in 3rd. I don't normally drive my car too hard, but when I do I notice a bit of turbo lag between up shifts. I know it's because I'm off throttle when I shift and because I take my time shifting and the turbo spools down because of it, but like I said, this isn't usually a big deal to me.

I wasn't interested in tooling around at high speeds or racing last night, just doing a few launches, short shifting into second, and then trying to flat shift into third to see how much it kills the turbo lag. I tried a few times without success; coming off throttle on an up shift is instinctive after 10 years of driving stick. Feather the clutch into a firm take off in 1st. At around 4,000 rpm clutch in, shift into second and come out on the clutch again when the motor has dropped revs to match vehicle speed going smoothly into gear. Blast up to around 5,000 rpm before going into third. Rinse and repeat three or four times without problems until I finally get my right foot to stay on the gas between 2nd and 3rd.

When I finally manage to stay partly on throttle between gears, it holds revs at about 4,000 before I clutch out into third. I wasn't trying to keep it pegged between gears, having not done this in a while and never in this car, but as I clutch back out I got fully on the throttle again. When it goes into gear, instead of killing turbo lag and getting a noticeable surge into gear, the vehicle accelerates hardly at all and my engine spins up to about 6,500. My clutch was slipping. Badly.

I stop. I smell clutch. I stop horsing around with trying to flat shift my car, drive home, and worry about what might be going on with my car since a lot of people on here seem to have very few problems doing this, and the first time I do it I glaze my clutch.

I've been noticing that my friction point has been getting wider over the last little bit. It used to bite early and bite hard, with a very small range of pedal movement between being out of gear and being in gear. Now it bites early, bites kinda gently, and it feels like the clutch is still partly disengaged until very close to the top of the pedal travel. I don't slip the clutch or do hard launches a lot, I rev match every shift up or down, I don't ride the clutch, and I don't keep the clutch pedal in at a stoplight (IE: sit in neutral clutched out, clutch in and engage first just as the light turns green). I've tracked it once, wasn't going to start taking it to the strip until the spring/summer as I finally start making some mods to the car to help track gains, and generally take it pretty easy with my shifts as explained above. I have 12,000 miles on this car over 17 months of ownership.

Has anyone else had any of these issues? If so, how did you resolve them? Get hard times at the dealership over what they consider a wear component? I've heard of other people having done hundreds of drag runs on the stock tranny without any issues. Having transmission problems after limited hard use and careful shifting in general is a fairly big concern for me, and I'm curious if it's widespread or if I am just an outlier.
 
Sounds like you glazed the clutch somehow during one of those launches. Could you have tried to control wheelspin with clutch pedal slippage rather than with the throttle? Not trying to say the crash was due to pilot error, just trying to diagnose.

I can't kill my clutch. At least not so far. Many, many hard launches. Just in driving between business appointments today I ended up at a redlight on a newly paved road with no one around. I did not do a clutch dump for a hard launch from first, but I did flat or power shift at 5500 into second and then again at 5500 into third, still having to modulate with the go pedal the transition to second. I was surprised that on that "green" asphalt that the tires lit up bigtime in third. Not just a chirp, have you, but an, "oh s***, I didn't really expect that much burn" of probably 40 feet.

If your clutch face is glazed and does not get its grip back after cooling down, you may have to go in and replace the clutch. I see no need to upgrade to a higher stage clutch or pressure plate unless you just want to, given how strong the stock clutch and pressure plate seem to be.

Another possibility would be something in the hydraulic servo part of the system that is not letting the clutch completely engage. But when you get that acrid smell, that tells me you're probably glazed and probably have a clutch disc that might now make a good Frisbee or discus.
 
And stop trying to power shift!! I only know of one other guy here that has had a slipping clutch, but he had over 60k on his car. I don't power shift, but when racing, I can squeal the tires good in 3rd :D
 
hey that guy would be me! what mods do you have? cause i had about 58k on when i got my DP and RP and thats when it started slipping on me.
 
Sounds like you glazed the clutch somehow during one of those launches. Could you have tried to control wheelspin with clutch pedal slippage rather than with the throttle? Not trying to say the crash was due to pilot error, just trying to diagnose.

I can't kill my clutch. At least not so far. Many, many hard launches. Just in driving between business appointments today I ended up at a redlight on a newly paved road with no one around. I did not do a clutch dump for a hard launch from first, but I did flat or power shift at 5500 into second and then again at 5500 into third, still having to modulate with the go pedal the transition to second. I was surprised that on that "green" asphalt that the tires lit up bigtime in third. Not just a chirp, have you, but an, "oh s***, I didn't really expect that much burn" of probably 40 feet.

If your clutch face is glazed and does not get its grip back after cooling down, you may have to go in and replace the clutch. I see no need to upgrade to a higher stage clutch or pressure plate unless you just want to, given how strong the stock clutch and pressure plate seem to be.

Another possibility would be something in the hydraulic servo part of the system that is not letting the clutch completely engage. But when you get that acrid smell, that tells me you're probably glazed and probably have a clutch disc that might now make a good Frisbee or discus.
I don't try to control traction in any car with the clutch. I have always tried to get on and off the clutch as quick as possible to minimize clutch wear, even in first. I wasn't really shooting for a fast hole shot here, anyway, I just went into first as per usual with a minimum of clutch wear before working up to third.

I'm also concerned that the hydraulics are having an issue, which may be affecting how much pressure the pressure plate is generating. Given the way the clutch pedal feel has been changing over the last few months and how the friction point has been moving and lengthening up the pedal, I think something is actually wrong. I know the clutch and drive train on this car are beefy, which is one of the reasons why this behaviour surprises me, especially considering I am putting down stock power, sans mods.

I guess I'll take it into the dealership to look at it and hope they don't try and tell me this is my fault.
 
It might just be a dud, I know of some Civic Si's that had clutches going out on them at 3,000 miles. Meanwhile my '99 Prelude with 167k still has the stock clutch.
 
Feathering the clutch into a firm take off in 1st is probably a chunk of the problem. I have read a lot of people doing that. Control wheel spin with throttle, not clutch! That IS smoking your clutch.
 
No, it's not. You "feather" or slip the clutch in first every time you take off from a stop. My launches were firm not hard, same as most of my regular daily driving, launching around 1,500 RPM and trying to get off the clutch as soon as possible while keeping the launch smooth. I said very specifically that I wasn't trying to get a good hole shot, and I wasn't regulating tire spin with the clutch. I was no where near cooking the tires in first. I don't get onto it hard until I'm in second (or fully into first, at the very least) when I can reasonably rev match all my shifts up or down either with throttle on a down shift or timing on an up shift.
 
Guys, I think you're both right but talking about two different things.

Yes, you do feather the clutch with a little intentional slippage as you tip into the throttle in first gear.

But the kind of feathering that glazes a clutch is riding the clutch at WOT to transfer the power away from the slipping tires to the lining of the clutch. Get great 60 foot times that way for about two launches then the acrid smell from the clutch and it's toast. The OP says he did not do that, so I lean toward either a defective clutch lining or a hydraulic issue.
 

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