Saturday, January 29, 2011


We got the tires off the old rims, and bought a Borrani 18" rim for the front wheel, along with stainless spokes to lace both 18" rims to the hubs.  An order of needed engine parts will come in this week, so the engine can be buttoned up better than new. 

The spokes were removed and the hubs will be polished and lightened where needed, the rear drum may or may not end up being resurfaced.  The front wheel and hub are fairly light and strong, and the Ducati rotor being used on the front end won't add much to the unsprung weight either, which will be good.  The back wheel assembly however, was awfully heavy and is going to make the back end suspension a touchy subject.  I took apart the assembly and decided I could start to shed some weight at the axle.  So I decided to make the axle again in titanium, as I still have about 20 feet left from a surplus find.

Titanium isn't much fun to machine, especially with a very old lathe, and no steady rest either.  The amount I could take off per pass was really limited by the need to keep the piece from flexing, so about an hour and a half after starting, I was doing my finishing passes.  Without the steady rest, I had to divide up the shaft and manually compensate for the remaining flex in the piece.  Not too bad really, wound up with an axle +/- .001 over the length, plenty precise for this old beast.  And it saved 10oz over the stock steel shaft, and is stronger too.

Monday, January 17, 2011

Building the XS Manx

Despite getting the business end of a screwdriver in his eye last week, Toby is back at the 650 engine, which is certainly a well engineered piece of metal.  The cam came out with little trouble, the manual specs a chain breaker to split the cam chain and extract the cam, but he managed to remove the end bearings and find enough wiggle room to get it out with ease.  The frame continues to shed weight, another hour of grinding left me with a pile of dust and useless crap to clean up, better on the floor than on the bike in my opinion, useless weight has no place on a real cafe racer.  We're planning on swapping the front forks for a set of larger XJ1100 units, the top and bottom triple clamps will be machined after we mock up the bike to measure some of the critical geometry.  The trees will likely be built with an eccentric adjustment for fork offset, to allow some fine tuning once the bike is on the road.  I'll likely be machining some cartridge emulators and building them into the fork damping system too, there's no reason to leave better roadholding out of the equation.

Wednesday, January 12, 2011

Building the XS Manx

This will be the story of the transformation of a cruddy old '83 XS 650 into a custom Norton Manx style roadracer.  My friend Toby Zeigler, a professional mechanic and excellent engine builder, and I have teamed up to complete this build.  With our unique skill sets, we'll have a machine that runs and handles better than it did the day it came from the factory, and looks as good as it performs.  This bike will be built to sell to a worthy buyer when completed, and we hope to be finished before the riding season really kicks in.  Of course we'll have it in ridable shape by the time the weather gets just warm enough to do a few hundred miles of shakedown rides before stripping the bike again for final polishing and powdercoating, etc.

We spent Monday afternoon getting all the extra junk off the bike and removing the engine for a complete professional overhaul.  Once apart, I realized just how ugly the stock frame is...