83 YZ125 K Restoration

Yep I've been playing with part numbers too. Sometimes you find it listed as 24X-XXXX-00 or 00-00 or -01 etc.

Here's my OEM front number plate off a USA yz125K:

Some more goodies for the engine:

NOS magneto coils:

 NOS reed valve petals:

 NOS water pump impeller:

 Nos coil pack:

 NOS CDI unit:

 To be continued...

Radiators fixed up. Came up pretty good considering they had a heap of bent fins etc. They're not 100% perfect but they'll get me out of trouble for now whilst the search continues for a set of NOS ones.

So I've been really busy with work and family stuff lately again so progress has been slow.

Ive actually been trying to hunt down an original salvageable pipe / expansion chamber to no avail so if anyone knows who has one let me know.

I have a DG pipe I could use but I'd prefer an original for the build. 

Another small update.

Finally found an original pipe and silencer for the old girl. They're a little rough around the edges but I should be able to make them look new again. Will post some pics when they arrive.

I have my brand new DG pipe for sale if anyone is interested in it.

 Cases primed with etch primer. 

 A few more progress shots of the engine. Found out today we were missing the magneto / stator charge coil "bridges" or what ever you call them so have a set enroute which will take about a week.

Care to elaborate what doesn't look right ?

Brand new carby for the bike. 

Here's some more pictures and progress of the engine:

Original silencer arrived..still waiting on the pipe.. both will get blasted and I'm thinking about ceramic coating them satin black.

Another small update

Engine is nearly finished now and I finally received the pipe I bought. Tomorrow the pipe and silencer are getting vapor blasted before I attempted to repair the dents in the pipe using a blow kit and heat.

I've searched yahoo Japan for parts but to be honest I've found more parts in America, Europe and Australia. 

Anyway, today I got the pipe and silencer vapour blasted. I was planning on using the blow kit and gas torch on it today to remove the dents but I'll have to get a few little pin holes repaired first.

Delayed once again...

Oh and here's the latest on the engine..

So I was playing around with the carby again and decided to swap the lever choke to the knob type as its period correct for the bike. Ordered a genuine mikuni knob style choke go to fit it up and it hits the carby.

Spoke with mikunioz (dealer) they tell me the knob type was never meant for the VM series only the TMX series.

Seems strange as oem ran a knob choke albeit smaller from what I can tell.

Here's the genuine mikuni choke:

 Here is the oem yamaha choke:

Learn something new everyday...

Keeping to theme as orginal as possible I've come across this NOS throttle cable adapter / adjuster. It's enroute...

Bit more info regarding the differences between  the yamaha oem mikuni and the aftermarket vm34-168.

So previously I discovered the choke plunger was different. The aftermarket vm34 comes with a lever and the orginal yamaha had a pull up knob. 

Upon closer investigation that's not where the differences end. The next thing that is different is the carb lid. The originals throttle cable adjuster is retained with a circlip and sealed on the face of the cap with and o-ring, whereas the aftermarket has a threaded cap.

Next thing I noticed that was different was how the throttle needle (6F21) is retained. In the orginal it has a little bracket that is retained with two Phillip head screws and a little locking bracket, whereas the aftermarket just has a drop in plate that appears to rely on the slide return spring to keep seated. The aftermarket slide also doesn't have the previsions for the oem retaining bracket.

 Apart from that the rest of the carb seems much the same...just putting the info out there incase anyone wanted to know...

Out of Curiosity I purchased the genuine mikuni carb throttle cable adapter to see if it would work with the vm34 carb and the genuine yamaha throttle cable.

It doesn't.... the little knob on the end of the genuine throttle cable that attaches to the slide doesn't fit inside the mikuni adapter.

Anyways the motor is now finished so ill hopefully have it back in the frame by the end of this weekend.

 Where's so close now I can almost smell it.

Motors in Here's a sneak peak:

 Next up is fitting all the radiators hoses, carby, chain  chain cover, finish the exhaust repairs, put the sticker on the swing arm haha...and a few other little bits.