BMW is no exception to this practice.  However, when they take shortcuts, they are often hard to spot.  Case in point, the shifting mechanism on the E36 M3/328.  From the factory, shifting is pretty smooth and effort is not that difficult.   However, after careful analysis, we have discovered a shortcut that was taken...probably something to do with saving money.

When you lengthen the lower portion of a shifter lever in a BMW, you get shorter shifts, plain and simple.  However, there is much more to the shifting formula than just doing this "simple" modification.

Most BMWs have a linkage rod which is near parallel with the shifter console.  Since the linkage rod is directly in-line with the transmission input shaft (the input selector that changes the gears), shifting is easiest and smoothest since it is a direct line to the shaft.  There are no angles or bends to get to it...it's as straight as you can get.  Most 3-series and 5-series follow this rule which is why shifting in these cars is generally very smooth and gear changes are near effortless.  Angles and bends create off-axis forces which increase effort.

The E36 M3/328 is an exception to this rule.  Since they come equipped with a shifter lever which has a longer lower dimension (shorter shifting) than most other BMWs, they actually bend the linkage rod (to gain clearance of drivetrain parts).

You can see that the force to shift the linkage rod is no longer in-line with the transmission input shaft.  For those that like to work with numbers, instead of being perfectly straight, the stock M3/328 linkage rod has a 17mm downward bend in it.  It's a sensible number since the stock M3/328 shifter lever is 14mm longer (on the lower part) than a standard BMW (325, 318, 525, etc.)  So, by bending the linkage to match, the engineers have gotten around doing the "right thing".   It is a small difference, but for people that are used to it, they do not really feel this difference...yet.  This is where BMW takes the shortcut.  Ideally, they should have make the shifter lever mount 14mm higher on the shifter console.   However, to produce a new shifter console (it's a cast aluminum piece) vs. simply bending the linkage is a no-brainer...save the money, bend the linkage rod.

When you add a "short shifter" to you car, this is when things get interesting.  Although not drawn to scale, you can see that by continually increasing the leverage of the shifter lever (lengthening the lower portion), the force to shift the linkage rod gets further and further away from being in-line.   Additionally, as the force gets further off-line, you need more force (effort) to shift the linkage.  Since the car did not come from the factory "ideally" set up this way, things are only getting harder and notchier to shift at this point.   For people that have installed M Roadster levers for short shifts, they've now increased the lower portion an additional 14mm over the stock lever.  Now, the bottom of the linkage rod is 31mm "off-line" from the normal, traditional, smooth-easy-shifting BMW standard. 

Coincidentally, the BMW M Roadster itself does have a "higher" mounted shifter lever pivot to compensate for the increase lower dimensions of the shifter lever.  Anyone that has gotten into an M Roadster will tell you that the shifting is easier and less notchy than a stock E36 M3.  Now you know why.

The solution to this short shifting dilemma.  

The UUC Motorwerks ERK (Effort Reducing Kit).  The ERK is a bolt-on pivot height adapter which uses the stock shifter carrier and bolts onto the top, raising shifter's pivot point and correcting the linkage geometry.  In some applications, a basic "short shifter" installation will misalign the linkage rod by at least 20mm off line.  With the ERK, it raises the linkage rod back to the original in-line position.

By raising the pivot the perfect amount, the linkage rod is now directly in-line with the transmission input shaft!   You now have shifts that are not only smoother than stock but also, the notchiness is gone.

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