Yesterday, 12:03 PM | #1 |
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Clutch Judder: Flywheel Heat-soak?
Hi all,
I saw an earlier thread on this but wanted to see if there were any recent experiences. I have a 2018 M2 I bought with 13k on it, it now has 23k, so still low miles. The car has many modifications, but isn't tuned currently... may have been n the past and I imagine it was driven hard. I've had no issues with it whatsoever. I've had the card for 1.5 years now. Recently I drove the car for a bit longer than usual (I don't drive it very far that often). By the end of some highway driving and then stop-and-go waiting to exit an off ramp, the car developed pretty bad "judder" when engaging the clutch to first. No issues with second, etc. Only from a stop into first. This has never happened before under any driving conditions. The next day, and since then (about a week now), when the car is cold there's no issue at all. Still, I have driven the car longer distances here and there and this issue never happened. I read in some other posts speculation that heat soak could be impacting the flywheel, causing some warping that leads to rough clutch engagement. I also have no idea if the flywheel or clutch is not stock (so many other parts are after-market it's definitely possible, but I have no idea if that's a common mod for this car). Has anyone else experienced this? Just curious, and while I will ask my mechanic, since this is new behavior, I'm curious if anyone else has experienced this. Could this also just be the clutch "going"? I've never had that happen in a car before so unsure what that feels like (again, though, it's not just slipping/not engaging, it's fairly rough judder/stutter). Any experience you have to share is appreciated, again, just curious. Thanks. |
Yesterday, 12:15 PM | #2 |
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my e90 and my old VW golf do that on occasion, usually moreso when its really cold out. I could theorize at the cause all day long but i definitely dont know anything for sure.
on my e90 shitbox that i dont care about, i just intentionally slip the clutch a bit to get things warm fast, lol. I wouldnt do that on my F87 though!! The clutch and flywheel in my e90 is relatively new too, so i dont think its anything going out. It might to some degree be failing engine or transmission mounts, allowing the drivetrain more movement than it should and more easily creating a slapping/oscillating motion thats felt as judder in the cabin. This is a complete guess.
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Yesterday, 01:19 PM | #3 | |
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Drives: 2018 M2 6MT
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It only occurs if I’ve been driving for awhile and I take it slow with the clutch engagement. If it get going quickly and limit the amount of time in the slippage zone, the clutch hooks up pretty nicely in first, even with everything fully warmed up. I noticed the judder is far more pronounced in Sport mode than in Comfort mode. |
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Yesterday, 05:49 PM | #4 |
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Experience this as well in my daily driven 2017. Got it with 1600mi on it, and it did it since new basically. This and the CDV bullshit where the bite point seems to move around is one of the few quibbles with the F87.
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Yesterday, 07:18 PM | #5 | |
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Yesterday, 08:06 PM | #6 |
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Dang. So this is normal-ish. I was beginning to think I was going crazy. How could I be so smooth leaving the garage, and so bad coming back? Doesn't help that I have a steep driveway, and I have to feather the clutch as I hit the driveway and into the garage.
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Today, 12:59 AM | #7 |
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I think the issue is a combination of oem throttle mapping, the dual mass flywheel and maybe even the oem tune (power/torque curve). Around 9 months ago I got a new custom tune/throttle mapping and instantly no more shudder.
Mileage at that time was 120K km and I'd had the shudder since very early km. Like others experience I had no shudder when cold, only when hot & only 1st gear from stationary or near stationary, in Sport was worse (Sport+ worse again). The cause seemed to be letting revs drop (even just slightly) after the clutch started to engage, that seemed to induce some sort of resonance with the flywheel/clutch. The softer Comfort throttle makes it much easier to smoothly maintain/slightly increase revs as the clutch is engaging but not so in Sport/Sport+ especially at low speeds of a carpark or stop-go traffic. Problem with Comfort is the rev hang and almost delayed throttle response (& I don't like the higher coolant/oil temps). I got the new custom BM3 tune and the shudder disappeared. This was my 3rd custom BM3 tune (1st from this tuner) and with all tunes I've had Sport+ throttle deleted & replace with Sport, so whether in Sport, MDM or DSC OFF I have identical throttle mapping. Even so with the 2 previous tunes I still had the shudder. The new tune has 2 changes, in the BM3 Map Configurator we set the "Throttle Response (Sensitivity)" at 10% for Comfort Mode (Sport on S55), note N55 M2 is same as S55 here. Left the "Eco/Efficient Mode" (ie N55 Comfort) at 0. This 10% setting makes the Sport throttle sensitivity identical to Comfort but without the rev hang/delayed response, so you don't notice any change in speed/acceleration switching between Comfort & Sport while maintaining the same throttle pedal position (at least within say 0-50% range). Also the new tune doesn't have the low down boost of the oem or my other tunes (Jordan & another from a local tuner), instead the power curve is much more linear with max coming later and holding, the other tunes fell off a cliff after 5600. Aside from the shudder being gone car is so much more fun to drive, upshifting 3-5K rpm is perfectly smooth every time, no more short shifting I remember reading a post recently from member Enabled where he mentioned a tune/throttle mapping he does for 6MT, if it does similar to what I have it's really worth considering. For anyone in Sydney Adam from Advan Performance did mine. |
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clutch, heat soak, judder, stutter |
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