Repair of idle mix screw thread
This video shows the repair of the idle mix thread: a thin alu-bronze bush of M8 / M7 x 0.75 is installed in the carburettor, realizing a very wear-resistant and strong thread Click this image to watch the video on Youtube:
Removal and installation of tappet guide bushings
In this video a method is shown to remove the old and install new tappet guide bushings from a 2 cylinder engine. The new bushings with an outer diameter of 24.97 mm have an interference fit with the crankcase. After installation, the bushings ID needs to be reamed / honed to give a tappet clearance of 0.02 – 0.04 mm Click this image to watch the video on Youtube:
Crown and pinion gear contact pattern
Staburag is a good alternative for “Prussian Blue” when determining the contact pattern between the crown and pinion gears. By adding a few lines, the contact pattern becomes even easier to read.
Flywheel R69
The R69 flywheel differs from the other / 2 flywheels because of the position of the ignition marks:
Smooth shifting R50 – R69S
A comparison of the required shifting force needed, between the old and new style shifting mechanism.
BMW /2 Swing arm leaks – final drive leaks by Scottie Sharp
Link to the original post: https://blog.scottiesharpe.com/2013/03/bmw-2-swing-arm-leaks-final-drive-leaks.html?m=1 BMW /2 Swing arm leaks, final drive leaks During a routine oil change, it was noted that the drive shaft housing was empty. Could it have been stolen by vagrants? A guy works hard for his oil just to have vagrants come and steal it. Well, before contemplating a move to a safer neighborhood, BMW riders should remember that oil migration from the drive shaft housing to the rear drive is a common problem. There are three ways that oil can migrate from the driveshaft housing to the final drive and they
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Testing valve springs
Valve springs can lose a lot of their strength over the years, as seen with this R25/3 valve spring: a new spring measures 16.6 kg, the old spring 10.1 kg, almost 40% lower. Lower spring tension usually causes no or minor problems on low revving engines, but it can lead to loss of power / misfiring on higher revving engines as a result of valve float The test device:
R50 – R69S Old and New style shifter mechanism
Comparison between the “old” and “new” version of the R50 – R69S shifter mechanism. Click following link for a comparison of the cam plates: Gearbox cam plate comparison
Fitting the correct distribution gear set
The number stamped in the crankcase (from -10 to +10) refers to the size of the crankshaft and camshaft gears installed by the BMW factory. After 60 – 70 years of service, the crankcase may have grown, which means that the original gear set may not be the optimal set anymore (0.01 to 0.02 mm play between the 2 gears). One way to determine the correct gear set number is to measure the c-t-c distance between the crankshaft and camshaft. This value must then be compared to the nominal c-t-c distance. This is impossible without very accurate measuring tools. The difference in
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List of fasteners R50 – R69S
A comprehensive list of bolts, nuts and washers for the R50 – R69S models Click image for list :