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      06-08-2011, 09:54 AM   #29
Seattle S65B40
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Drives: 2008 e92 M3
Join Date: Jan 2011
Location: PNW

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2008 BMW M3  [0.00]
Quote:
Originally Posted by SenorFunkyPants View Post
Seems like there are two issues here:
Baulking into gear - usually there is a "baulk" ring in the gearbox whose purpose is to resist the selection of a gear until the synco ring has matched the speed of the selected gears to provide a smooth engagement.
Grinding into gear - caused by (assuming the clutch is disengaged) - brute force shifting, trying to shift too quickly before the synco ring has speed matched the engaging gears.


In either case the answer is in the timing..there is a speed for every upshift that would give a perfect shift even if you had no syncro mesh at all, you just have to practice until you find it. Similar with baulking on the downshift, you have to add a little throttle, timed so that the engine speed matches the gearbox "speed" when you engage the gear (may need to double declutch if the box is cold or extra reluctant).
It seems that the most significant and reproducible issue with my tranny is downshifting into second. Although I experience grinding in upshifts from 1 to 2, it is very rare and under HARD acceleration - thus, i understand it is a feature of the transmission and i need to slow my shifts.

Even with double clutching and rev matching, i have to pull very hard and through some significant resistance to get down into second at any speed over 10 MPH.

Finally, something that i've noticed since I bought this car, is that 2nd gear moves in the gate as I engage the gear. More so than any other gear. Is this normal? Like it literally lurches forward a bit and I can feel vibration.
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Club 6MT
2008 E92 M3 6MT, AW/Blk Ext., brushed aluminum
2006 E46 M3 ZCP 6MT Carbon blk/blk(sold)
2001 E46 325Xi 5MT Jet Blk/Blk (sold)
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