But I was kind of in denial (I thought the rattling was due to poor quality of the new cham chain) and it was at the beginning of the winter. And I urgently needed the NX because I didn’t want to corrode any other of my bikes.
On a drive back home in October 2013 the rattling became suddenly frightening - but I was on a highway, which is not a good place to shove your bike along. I tried to reach the next exit ramp, which was only 2 km away. That was the second big mistake, since it turned out that the lower connecting rod bearing disintegrated, causing the piston knocking on the valves.
After a few hundred meters the engine finally gave up (for the first time ever) because the piston finally had beaten up two valve, and with no compression left in the cylinder I had to shove (for the third time in 15 years, once I had a broken chain link due to poor maintenance and the other time a cheap Chinese CDI failed) the NX to the next exit. Which is a special treat on a German highway when cars passing you only inches (actually most highways have breakdown lanes, this one didn`t) away with 180km/h and more …
oct 2013 - shortly before desaster
During disassembling the engine, I noticed only very few signs of wear. The gears were still in good condition, except for one damaged by a needle of the disintegrated rod bearing. The oil pump was ruined by brass flakes of the rod bearing, as a result, the oil supply to the cylinder head and piston ceased. Surprisingly, the cams did not show any signs of damage or wear. A bit more damage was done to the valves – two of them were screwed by the piston (so I guess I could call myself valvecrusher as well
![Rolling Eyes :roll:](./images/smilies/icon_rolleyes.gif)
note that the upper two valve pockets show signs were the piston hit the valves
Amazingly, the cylinder was still like new, even the cross grinding was still visible – this nicasil coating really does a good job. Besides this, I only had to replace the sealing of the water pump and of course all engine bearings.
So after this experience I would recommend the following.
If the Nixie starts to rattle take a look at the oil filter first. If the metal flakes in there are silver colored, it’s the timing chain grinding at the cylinder head => change the timing chain (usually necessary around 80.000-100.000 km) .
If the shavings in the oil filter are golden colored, it’s brass from the lower connecting rod bearing. Don’t drive any further and get yourself a new crankshaft. They are not that expensive (as long as they are still available). Unfortunately, OEM connecting rods were never sold separately – does anyone know if there are aftermarket rods available?
oct 2014 five months and 4000km after resurrection