BMW R75/5 Restoration (1)

More than 200,000 km?

According to BMW Sherb, who took the engine apart after we had shipped it to Germany, it had probably done a lot more than 200.000 km. Below are a few pictures of the wear.

The crankshaft

The major reason why I wanted the engine fixed was the “clonk” sound coming from the engine housing when the engine was hot, which indicated worn crankshaft bearings. In the old days one would have brought the crankshaft for grinding the bearings off to the next size and fitted oversize bearing seats, but because labor is so expensive in Germany it was cheaper to buy a new crankshaft.

Crankshaft bearing seats

The bearing seats of the piston rods were heavily worn.
Heavy wear also inside and outside the back and front bearing sea

Camshaft

Wear and pitting on the cams. 

The centrifugal timing advance was welded onto the camshaft. I had to use a grinder to remove it. It did not make sense to consider repairing the camshaft because the the cams were worn anyway but it shows how the local mechanics fix things. Instead of trying to do a proper job they usually use quick fixes that might help in the short run but cause problems in the future. 

Piston rods

One of the piston rods had cracks in the eye and needed to be replaced too.

The oil pump

As expected considering the overall wear of the engine the oil pump also had signs of heavy wear and needed to be replaced.

The electrical system

This was one big mess. After finding all the problems it was a miracle to me how the motorbike could run at all.

Part 2: The Restoration