Clutch and push rod

Since I don't have any copper washers in my workshop to fit the sump pan, I started working on the clutch.

The thrower seems to work good, so I put the flywheel back on.  The clutch lining was full of oil and grease, so I tried to wash that out as best I could with brake cleaner.

The big project was creating the new push rod.  My workmate Mike had already made the pushrod receiver that I tack welded to the square hole in the pressure plate.   I wanted to make sure it wasn't going to come out and get jammed in the shaft somehow, hence the tack weld.  It shouldn't, but I didn't want to chance it, and I didn't want it to start turning either, since the shaft into the pressure plate is round instead of square.

I took Wilhelm's full length measurement (225mm) from the surface of the pressure plate to the end of the rod and cut the 1/4" drill rod that had bought to fit.  I squared up the ends in the lathe, gave them a slight chamfer and then polished them up to a high shine.  Drill rod (aka silver steel) is fairly hard so that took a while.  I test fit it in the gearbox and it looks right.  I can drop the rod in after the gearbox is mated to the engine.

I decieded against a ball bearing at the clutch end for now.  I can always cut the drill rod more and fit the ball bearing later if I think its not working right.

The next fun part will be to compress the clutch springs enough to put the nuts on.  I guess a few clamps around the flywheel and pressure plate may do the trick?

Cam Chain Tensioner Plunger - Fabricated

Well, with no stock specs for the cam chain tensioner plunger, I attempted to make mine "to fit".  Which meant assembling and disassembling a few times, and a few times in the lathe.  Thank goodness I bought a self-centering chuck.

I started with the hollow brass slug that was the bodged part.  I threaded it partway from the outboard side, relative to the engine.  This way if the set screw were to back out, it would not fall into the engine.  The set screw gave me a tunable platform for the inner-small spring to push against.  I then proceeded to remove material from the slug until it got me an equilibrium on both springs.  This way the tensioner could float properly as the chain moved.  This was all hit-and-miss machining.  I didn't even measure it in the end.  I just took a little more off until it fit.  I tuned the set screw in until I got the right travel on the springs.

The book said that the locking bolt should be tightened at the minimum position of the plunger.  With that set, I buttoned it up.

The next task will be to try my hand at metal spinning in the lathe to make a suitable crankshaft oil slinger disk.

Bodged Cam Chain Tensioner

It appears my cam chain tensioner has a bodged plunger.  I checked out the parts drawing closely and its certainly not like the one shown.  Once I had fitted the new chain from Stewart Engineering, it was apparent that the bodged tensioner no longer worked correctly.  The tensioner assembly cannot be screwed into the block, since the bodged plunger is too long and has no smaller spring.

I've asked on the Classic Glory list to see if anyone can get me some dimensions.  Just my luck the part is not presently available new, so I'd have to fabricate one.  Lucky I have that lathe.

The good news is that the head and head gasket went together flawlessly.  The new stud in the back went in easily, and I managed to set the valve timing like a pro, thanks to the Sunbeam Owners Bedside Book.

Ring, Ring, Ring

The book says there should be a mark on the compression rings to show which way the TOP is.  BZZZZ, Wrong !!!!  Not on these.

So I got out the micrometer and tried to measure the taper.  I did my best and tried to find which side was consistently the smaller width to show which the narrower taper should go up.  (No one wants to pump oil into the cylinders)  I just hope the castle nuts for the big end bolts line up nicely to get the cotter pins in.

Here's the box from the rings.

Here's the box from the new cam chain.  I'm not THAT far yet with all these interruptions, but I will be soon.

Red Inner Tube

When is the last time you saw a red inner tube?  That's gotta be an old one.  Its only got two patches on it but holds air.  It came out of the front wheel.

The rims look pretty good.  They'll need scraped down and the surface rust removed, then given a shot of paint.  I can't see putting them back together without.  The rear rim is worse than the front, not sure if that is lack of cleaning in the past, or heavy braking on the rear.  The DURO tires came in last week (by recommendation of my brother who runs them on his Ural), they look pretty good.  They're nice and FAT-looking.  I got them at a good price from Tires Unlimited

I'm being tempted to paint more and more things.  The center stand is next on the list.  Its nearly devoid of paint and really needs to be protected.  I want it to be original, but I also have an urge to make it "pristine" rather than the "patina" I originally planned on.  I know once the painting starts, its hard to stop until everything is repainted or re-chromed.  Somebody stop me!

Decided on tyres

The original Dunlop tires are completely petrified hard as a rock.  I did some research but didn't want to pay for Avon tyres for a show bike that may not get lots of miles.  I discovered Duro makes a vintage tyre that is wide enough for the S7's bulky appearance.  The HF-302 on the front and rear should do the job.  I got both tyres, tubes and rim strips for a little over the price of one Avon Safety Mileage MK2.

XS650 Done

After adding a Pamco igntion and a dual spark coil, the XS650 runs reliably.

Many thanks to the members of 650Rider and XS650 Garage.