Again, I've left it too long between updates.  However, I've made some real progress on the YZ80.

The next part of the restoration was the front suspension.  This was something that I wasn't looking forward to for some reason but in the end it turned out really well and was quite enjoyable to do.

The forks were leaky, the front wheel had been painted in thick, black paint and the spokes were mismatched and rusty.  That's probably why I wasn't looking forward to getting stuck into it!

The last time (a looong time ago) I've been involved in stripping down a set of motorbike forks I ended up getting stitches in my head (thanks Dad!) - maybe another reason I was apprehensive!  This time it all went well, no trips to emergency.

The forks had no oil in them, just some old gunk.  Plenty of cleaning of all the parts  and then re-assembly with a rebuild kit and they came up really well.

The triple clamps were cleaned, blasted and painted in the closest silver I could find to the original finish.  All I have is a before shot of them:

The handlebars were next.  Unfortunately they had a bend in the crossbar so some heat and some persuasion and they straightened up like new.

And then the part I dreaded most.  The front wheel.  No better way to do it than just get stuck in.  First, the easy bit.  Strip it down - with bolt cutters of course!

I then stripped the flogged out bearings out of the hub and blasted and painted that.  With new bearings pressed in and new seals, it came up like new.

The rim required heaps more elbow grease.  The black paint was very thick and hard to get off.  My little sand blaster struggled with it so I had no choice but to paint strip it.  I hate paint stripper!

Underneath the rim was in decent condition but still had some light scratches and corrosion so I need to fix that up.  The original finish would have been silver anodised I think.  Rather than have that done and potentially not be right, I thought Id have a go at painting it.  Glad I did because it came up great - the finish looks just like the original.

The paint is actually a chrome plate look-alike.  It costs about $20 per can but it's good quality and well worth it.

I managed to find some NOS (New Old Stock) spokes.  So, next job was to re-lace the wheel and hub.  This turned out to be much easier than expected and was good fun.  On these rims the spokes are all the same length and bend.  So, they can only really go in one way.  If you are methodical and patient about it, they all go in easily.  Best tip is to have a photo of the rim with he old spokes handy.

I then trued it up on the bench, tensioned the spokes and temporarily installed it on the bike.  I've managed to find the original style Dunlop tyre for the front which hasn't been made for a while (you can see it in the pics below).  I'm still looking for a rear.

I had a NOS brake disc so I put that on the hub with new bolts.

So, it's getting really close to complete now.  Brakes, rear wheel, tyres and then the decals.

Wow!  It's been a long time since the last update.  Things have progressed slowly on the YZ80 project due to me being distracted with the Mini.  I've been busy planning and collecting parts for it - to be detailed here soon.

Untill then though, I really have to finish the YZ!  The last thing I want to do is have it sitting here 75% done for the next few years (I'm really good at that!).

Ok - an update on the YZ:

So, one thing that I've been looking for is a new airbox.  The one on the bike was a bit tired and had one of the cast-in nuts that fastens the box to the frame was chewed out and missing.  Problem is, the airbox was unique to the 1993 and 1994 YZ80's.  In 1995 they changed slightly for some reason.  As a result, the original box is hard to find. So, I fixed this one.

First problem was the chewed out mounting nut:

It looks as though someone has got a bit excited with the spanner and twisted it out.  So, I went to the hardware shop in search of some sort of castable epoxy resin.  I found this stuff instead:

It's an two part epoxy putty.  I'd never used it before but figured it would be worth a go.  It worked perfectly!

Once set, this stuff is very hard and feels as strong as the other cast - in nuts.  A bit of sanding and that job was done.

The rest of the work on the airbox was just some elbow grease - cleaning, blasting and sanding in an attempt to smooth out the years of battle scars.  After that, I primed it and painted it in a black paint that looks almost identical to black plastic.  All in all it came up ok considering how it looked to begin with. 

Installed on the bike it looks even better.

With that done, I was able to fit up the plastics properly for the first time.  It's looking more complete now!

Next - front end.

A few more things completed on the YZ project.  The first was the fuel tap.  A pretty simple job really.  First job was to strip it down.  Doesn't look very happy to be apart!

Once it was stripped down I compared the parts found to those on the Yamaha parts diagram.  It must have been leaking at some stage because someone has added two extra seals that shouldn't be there.

The main body and lever are aluminium and have the same finish as the carby body.  The front plate thingy is steel and looks like it was zinc plated. 

As with the carb, the main body and lever were lightly sand blasted and then soaked in kero to get the desired finish.  The front plate was cleaned and sanded with 2000 grit paper before zinc plating.

From there it was just a matter of reassembling with new seals and screws and then installed on the fuel tank.  Job done.

One part that has been bugging me for a while was the chain slider / guide that protects the swingarm.  The one that was on the bike was well worn so I sourced a new old stock one.  Problem is, instead of being a nice black plastic, it was an ugly army green!

Looking through my collection of photos of 1993 YZ80's showed that when they were brand new, like in the magazine tests etc, the chain guide was black.  All of the second hand bikes show them in different shades of green.  Strange.  I can only assume that they loose (or gain!?) colour over time with UV exposure.  Even though my new old stock replacement was still in the original packaging, it had turned 90% green.

Anyway, I wanted it to look new - black.  I could have painted it but thought that was a bit dodgy.  So, I thought I'd have a go at dying it.

I used some Rit fabric dye that I found on eBay.  It comes in a little packet in powder form.

First step was to get a pot big enough to fit the part in, fill it with water and get it hot on the stove.  I had it just below boiling and then added the dye powder.  I wasn't sure how much to add so I just put the whole packet in and mixed it up.

Once it was mixed I backed off the temp so it was hot, but not bubbling at all.

Next, I used a zip tie to suspend the part in the dye so it wouldnt be resting on the bottom.  I figured that if it was resting on the bottom it could potentially melt and it wouldn't get an even coverage of dye.

With the part hanging on a piece of timber and in the pot, I left it to cook for about an hour.

After about an hour, I took the part out, gave it a rinse in cold water and dried it off.  Luckily, it worked!  It looks like brand new black plastic again!

Today I made some more progress.  Unfortunately I didnt get any progress shots but I've now finished the rear shock and also re-plated the footpeg assemblies.

The rear shock seemed in good mechanical condition.  The hardest part was color matching the pink spring.  In the end I had a friend mix up the correct colour for me - matched by eye.  Came out spot on.

Footpegs and their springs were cleaned up, repaired and then zinc plated.

Here are some pics of the restored bits installed:

And for good measure, I temporarily held up the sidecover and bolted on the rear guard to see it more completed.  Happy so far!

Not a huge amount to add today.  However, the YZ is one step closer to completion with the exhaust system now finished.

No real rocket surgery here so I'll let some photo's do the talking...

Getting there!

YZ80 Engine

You might remember that I mentioned the engine in the YZ ran really well.  To me, it ran as good as it would have when new - plenty of compression, easy starting, nice and quiet and a steady idle.  Doing anything mechanical wouldn't have improved it.

So, the engine just needed a cosmetic freshen up.  Easier said than done!

Before I did anything, I noted the different surface finishes of the different parts. 

The head and barrel appeared to be raw aluminium - as cast.  A light blast in the sandblaster would achieve the same. 

The crankcases looked to have the same finish as the swingarm.  I had the paint sorted for that.

The clutch side cover was a brighter silver colour.  It also had a crack in it so it would go in the bin.  I sourced a new old stock replacement which made that side easy.  The magneto side cover was plastic grey - again, I had a new replacement for that.

To do it properly, I stripped it completely so I could start from bare cases.  Whist the outside looked pretty ratty, inside looked really good.  No work needed.

With the cases bare, they were cleaned, lightly blasted, cleaned again and then painted in the same paint used on the swingarm.  No gasket in between them so some ugly gasket goo went on and then the first part of assembly.  New seals and bearings for good measure too.

Head and barrel went in for a sand blast and came out looking spot on.

And with that, along with a few other bits and pieces, the engine was basically complete and looking much better than what I started with!

Im still waiting on the clutch cover to arrive from the States but I couldn't wait to throw it into the frame along with the new radiator and water hose.  Luckily Doug the master bike mechanic was on hand again to remind me how it went together!

Next, I thought I'd have a go at restoring the carb.  At first it looked pretty ugly.

An overnight soak in kero, some light work in the blaster and then another soak in the kero bought the body up looking like factory again.  New screws and fittings and it all looks pretty good again.

And onto the bike with new fasteners.  I threw the new seat and tank (which im not happy with - a story for another day) on for good measure.

And that's it, for now...