I've always enjoyed motorcycles, too.

Ride Photos Page

Above as  it was in 1992, and below 14 years later

 This is my most current project, the overhaul and restoration of  this 1979 Yamaha XS-650.  

Looks pretty good from 15' away, but sat idle for 5 years after developing a troubling

motor noise, suspected to be related to the cam chain and tensioner assemblies.

Sure enough, excessive cam chain flex was found.  Old chain on bottem at

maximum flex, as compared to new chain on top.  Flex was enough to allow

"waves" to form in chain, which caused "slamming" of  tensioner assembly

 at full travel of plunger against adjuster barrell.  Missing plunger damper

washer contributed to the loud and worrisome "Clack" at every revolution of crank!

Note that cam chain stretch not nearly as evident.  New cam chain is on top, old

on bottem.Both stretched straight from equal origin, only about 3/16" difference in stretch.   

Thankfullly, aluminum flakes found in oil filter, traced to sides of cylinder cam chain cavity,

were not found in oil pump, or elsewhere. so motor, with new cam chain, new valves,

honed cylinder, new standard rings, new sump strainer, oil filter, gaskets, "0" rings, and

seals, will soon be going together!  I'll bead blast the cam cover, head and cylinders, and

refinish with silver wheel paint.  Buff and polish the case covers, etc, and clear coat

before re-installing in cleaned and repainted frame.  Then add new swing arm bushings

and fork seals, steering bearings, overhaul the carbs, flush & seal the fuel tank and

petcocks, and I hope to have a nice around town cruiser, like the one I owned 20 years ago!

PISTON INSTALLATION ATERNATIVE

I don't have two ring compressor tools, and couldn't find anyone who sold them at

a reasonable price.  Hmmm!  Maybe there is another way than Clymer shows!

I first installed the interior piston pin clips, that is those that would face the inside

of the motor.  Then, used a standard automotive ring compressor tool to install

the pistons one at at time into the cylinder from the bottem.  I then carefully

positioned the pistons such that the pin holes were just below the cylinder skirt,

and the rings were still held in place.  Then the whole assembly was lowered onto

the studs, onto two 3-1/2" wide wood blocks, one front, one rear, both held in

 place by a rubber band.  These held the cylinder and pistons at a convenient

height while during the rest of the procedure.  The pins were then pressed in by hand from

the outside toward the inside of each piston/cylinder.  Slight rotation of the crank

shaft helped line up the rod small ends with the pins. Finally the outer pin clips

were carefully installed with needle nose pliars, without disturbing the piston rings

precarious postion just above the lower edge of the cylinder skirt.  Success!

I don't imagine I'm the first to intall motorcycle pistons this way.

Note:  this task MUCH easier with the piston pin clips from Mike's XS, which

have a thoughtful little tang on them, making gripping with pliars no challenge at all.

MUCH more user friendly than the plain round clips this motor had to start with.