Monday, March 26, 2012

R1100S winter rebuild - part 6

This is one of the last update on the BMW's rebuild ... well hopefully. In this issue of "how to start a rebuild way too late and make it last 'til summer is gone", you will read the joy and pain coming along with the rear end fixing. It just started with the simple intention of changing the rear shock, but then the idea of fixing the exhaust end cans - they're jumping in their slots on every bump - popped up. I could not imagine this would end up in yet another broken part in desperate need of a welder.

Ok, then let's start with the part that ran rather smoothly. The rear wheel's been removed to give extra working room and also to make the rear dead shock easier to remove. Then the swing arm has been cleaned and the shock swapped for the tasty Nitron which is been set up 12mm longer to 325mm in order to raise the bike.

The knackered eleven-year old Showa

Why not clean parts while there that accessible ?

Old compared to new

A serious upgrade over the old Showa

And while the rear wheel was off the bike, the bolts on the end cans were much more visible and the problem easier to locate on the exhaust. At first I thought all I had to do was to secure the retaining bolt with a lock washer and try to tighten the bolt a little harder. But then it all went wrong as I discovered what the real issue was. The main bolt screws into a nut with a shot thread. But wait there is more to that than just a nut with a shot thread as the latter is welded to the end cans support bracket and cannot be simply replaced with a new one. 

Left : the end cans of the Laser race system. Right : this nut in the middle is dead.

The bracket needs a welder. "Allo, Metal Machines ? Yeah it's me again ...". The guys looked like they were flooded with work and told they could not fix the parts as quickly as I imagined. I guess I'm giving this build another week ...

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