Restoration Part 1 - Motor

Well, although I was going to start this DURING the winter, I've finally started ... now. Well I took the PC apart two weeks ago, and am SLOWLY starting to get rolling on it.
Why? Well, although it was running last year, a few things bugged me. Occasionally a hint of smoke was appearing ... and well performance ... can always be better. It's always bugged me the way the PC looks as well. Sure for most people its all good, but I think she just needs a good make-over. Besides, last years dissection to re-machine the crank didn't include anything more than that seeing as i was more in a hurry to ride and see whether I even liked the damn 'ped. There's one thing I hate, something that doesn't run right, or has the potential to let you down. When you're for example riding around say Lake Simcoe, and you're clocking around 250+ KM in a day ... the last thing you need is a break down ... especially if you had one of those "I knew it ..." feelings.

So enough babble! On to the pics, now more will be posted as I get further, assuming
I don't get lazy again and stop posting altogether ....

Here she is, my 1972 Honda PC50 ... still in one piece:

And without motor ....

Here's the motor all by itself ....

Ok heres the head and the top of the piston ... note that build up ... remember ... its a FOUR STROKE .... I knew we had a problem!

Take off the side cover ... the clutch!

And now without clutch ... isn't it wonderfully simple!

Split the crank case in half and we get to to the good stuff! Elegantly simple system, which is perfect, not much that can go wrong here is there.

Gutted, we have the bare case now sure i'll be doing some work on it, but one thing I hate on the Japanese motors is the painted Die Cast cases, now when new, they look just great ... you add 30 plus years to them, a few owners, and you get this dull finish, paint worn off in places and it looks, just sad. Now sadly, as you'll see on a few other pics later, there is HEAVY pitting on top of the cases where it goes into the frame, due to a mouse nesting up there during years of storage. Not much that can be done ... well yes there could, but to be honest, I am aiming for a relatively fast restoration, and don't want to spend a year or more on it to get it perfect.

Before we go nuts, and start painting the cases, we need to glass bead the case. Now to avoid getting too much glass into the case itself, I always plug every hole in the case, here I made aluminium plugs, quick, easy and will protect the sealing surfaces, and the bearing seats from the glass beads ....

Another look at more plugs ...

After the glass beading ... you see how matte the surface is, perfect for painting ...

Here you can see that pitting i was talking about on the top of the cases ...

A quick preview of the painted cases, bad photo ...

Now having the cam out, I noticed the extreme wear around the oil pump driving end ... look closely on the right, the cam is on the lathe ready for machining ...

Now since the camshaft end was machined down to get rid of the score marks, we have a problem, the bushing it goes into is also worn, and besides now it doesn't fit at all obviously. So, yup you guessed it, I get to make a brand new bushing. This bushing is a pain in the ass, first its going to have to fit the case, no problem, except there are two stamped cutouts on it which hold it in place, so the new one has to have those too. For the Aluminium camshaft to successfully run in the steel bushing, the surface of the bushing has to be as smooth as possible, and hard to avoid scaring which will cause the cam to rip its surface. Solution? Make a bushing, fit the slots to the case, harden it to around 60 rockwell, and finish turn it using diamond. Result? a mirror finish ... ok the photo again is crap, the camera doesn't like me! Also check out the re-machined camshaft end .... the better the surface, the less chance of wear. Also the fit is important. too much play you get wear, too little gap, not enough oil will get in, and wear will occur again. Tricky, but all possible! Look at that scoring on the old bushing in the front ... ouch.