Changing bits

So on with replacing bits.

First up - the clutch plates.  No problems (ive had the clutch apart before when I first got the scoot so I was cool with this)

Next up - Stripping the secondary shaft in order to replace the gear-change cruciform (aka 'spider' though im not quite sure how a 4 legged cross resembles a spider).  Without even looking at it, Dan had recommended changing this while the engine was at this level of overhaul.  And he was right, the original cruciform was quite heavily worn which can cause gear-change slips.  Apparently the cruciform is made from a relatively soft metal and is in essence sacrificial in order to protect the gears from damage

And then I sort of titted about for a while - cleaning this bit and polishing that bit.  I was avoiding the decision to change the main bearing.  Ive read all sorts of recommendations for changing this bearing, and Ive read all sorts of warnings about getting it wrong so I was a little anxious.  However in the end you simply cant tit about all day, and so I went for it..... and it was a piece of cake :-)
I didn't get to photograph this process as due to all the fretting, So, to any other PX main bearing virgins, heres what I suggest you do...

1. Get everything nice and clean and dry
2. Get a comfy, clean and clear working space, and set up some blocks of wood to hold the engine case level and solid for when it comes to bashing the bearing - I happened to have a few pieces of 2-3" dia bits of tube which I used for bracing the case to hammer against - I used these, but in retrospect I think I could have done the job without these
3. Remove the retaining circlip - this was the biggest hassle for me. My circlip pliers were up to their max on this one, but with a fair amount of persistence, i got it out without pinging it across the garage
4. With a hand held calor gas flame (the sort you use for paint stripping) i warmed the engine case around the bearing.  Just like the bloke does in the youtube video I posted earlier).  I reckon I played the flame around the area for 4 to 5 minutes trying to warm it up evenly.  I wasnt sure how hot to get it, but didnt want to over do it.  I took it to the point where the aluminum engine case was too hot to touch with bear fingers.
5.  Turn the engine case over and onto the wooden blocks you set out earlier and get ready to knock the bearing out - I used a 2" square block of hard wood as a drift.  Using a regular hammer, I knocked the bearing out - i reckon that I hammered no harder than I would knock at a front door - ie - this is not 'belting it out', or 'whacking it out' - this is 'tapping it out'
It came out without any fuss..... so why not pop the new bearing in while the casing is still hot and expanded?
6.  I cleaned the bearing housing out, and squirted a good load of engine oil around the place
7.  I DIDNT chill the new bearing like the bloke does in that youtube video, i didnt even put it in the fridge (which I had considered).  I simply offered the new bearing up, and pressed it as far as I could, then with a block of wood as a drift again I TAPPED it home - Dan had warned me of not knocking too hard as some people have been known to knock the case lugs off the back of the bearing housing
8.  Put the circlip back - and watch your eyes, as it spitted oil at me when it snapped back into place!

And that is it!  Simple!  slosh in some engine oil, tap in the oil seal - job done!
I was delighted, and celebrated by decarbing the piston, barrel and head