 You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
Hi,
Does anyone have a manual 3 series of this ilk? We bought a 320i over the weekend and we're over the moon with it, however, 3 days in I'm struggling to finesse my gear changes especially 1st to 2nd and also high rev upshifts at say 5000rpm 2>3 or 3>4. I get an almost double jerk forwards.. not good at all.
After a bit of googling there is a wealth of content on the usual motoring forums about a device BMW fit called a clutch delay valve (CDV) that is designed to protect the drivetrain from shock by restricting the flow of fluid in one direction (when releasing the clutch I think). The valve is in between the slave and master cylinder somewhere and I think it essentially protects the drivetrain should the driver say side-step/dump the clutch.
Now I'm all for systems that protect important and expensive components in my car but this feels like the majority are suffering to protect a few who don't know how the drive a manual. The main symptom is that the clutch does not behave like any other I've driven - the engagement point is different on depression (say 3/4 down) than release (maybe 1/2-2/3 back up).
Has anyone experienced this first hand and are there any tips on improving the quality of my shifts?! I think my old 325i must have had this too but the big 3.0 inline 6 (or the lack of a turbo) may have masked the behaviour to some extent. Apparently there was a simple 'delete' available on older cars but not for this one as it is integrated into the system somewhere..
Any thoughts very welcome!
They've been using them for years on most of the range. Plenty of kits to by-pass them, or take it off and run a drill through it....
Thanks Michael - I'm seriously considering getting something like that done! Hopefully it's something my local BMW independent can do.. It makes me wonder about the worth of a manual 'box at all these days but our other car is an auto and I don't want me or the wife to get out of practice driving a stick.. hey ho.
I had a BMW with this and learnt to drive round it, but it was awkward when changing cars etc. Simple job for a BMW Indy to remove. IIRC they were primarily put in to make it easier for Americans to use a manual gearbox.
It's absolutely crazy! I'm having to re-learn driving a manual... despite having driven one for 15 years. Aside from the moving target of a bite point it also feels like the natural rev drop as you dip the clutch for an upshift isn't matching revs for a quick shift.. i.e. I have to wait a bit longer for the revs to drop before fully releasing.
the bite point doesn't change, it is just delayed (well, damped). if you move your foot slowly off the clutch, you won't notice any impact, if you sidestep it/lift off quickly, you will.
I guess that if you're noticing it, it is 'protecting' the drivetrain from your driving to some extent. it might not be wise (from a logevity perspective) to remove it
Thanks 5lab. Just had an interesting conversation with the indie saying that he is not convinced the car even has a CDV as he can't find it on the official diagram or the parts list and the price of the slave unit is so low from BMW he suspects it may not be in there either.. He even said he had people with E90's come in (where the CDV is visibly in the line between the two cylinders in the American market and the cars don't have it!
Maybe I just suck at driving!
As above, been on the cars for years. My old E46's had them...eventually you get the knack of it.
I would be surprised of that is what's causing the issue. I thought it just protected the drivetrain if you really dumped the clutch at high revs - I don't think it should be noticeable in normal driving.
It was massively noticeable in my old Z4.