YZ125K Rebuild

[alexbrown64]

Whats wrong with copper washers Husky? 

[FourstrokeForever]

Yeah....nothing wrong with copper washers 

[80-85 husky]

copper washers fine, comments about burning could easily be misconstrued by the jury.....

[alexbrown64]

I edited it to reflect the fact that it was a joke Husky... wouldn't want anyone to think i go around burning missusses 

[80-85 husky]

good move now back to that bike....

[BJJ]

Very nice looking Bike Alex,  and thanks for sharing all these tips and information on the things that you learnt lessons from.

[alexbrown64]

Your welcome BJJ.  I get good advice from the members on here and these builds give everyone ideas.  I also keep the website updated with all the updates, parts, articles, tech document etc.
www.yz125k.weebly.com

Cheers,
Alex

[Ekka]

Very nice job Alex 

[alexbrown64]

YZ125K Ride Report:

Day one, got into the bush and went for my first ride on the bike.  I have warmed it up at home a few times but i still needed to run it in under load, so i puttered around a bit.  First pic shows the setup i have for getting it all out there. Intial feel of the bike was great.  Suspension worked well and bike felt good.  A lot of smoke and spooge coming out but i need to open it up a bit to find out whats what.  OK, second pic is a minute before bike broke down.  I took off again and got 20 seconds down the track and it died like when you run out of juice.  Checked fuel tap...noop. A wiggle here and a look there, but she would not start.  Pushed it back to car and went home to wash her down and investigate.  Ended up being NGK Iridium plug.  Just 30 minutes old and packed up.  Maybe because of the oily bike.
I checked timing.. a bit off.. it was 1.4mm btdc.  I reset to PVL recommendations at 1.2mm.  Next was the spooge. I had put a 50 pilot in as thats what the Yamaha Race Report said was the hot ticket for the upgraded 36VM.  The modern day 36VM comes prejetted with a 35 pilot.  I put the 35 back in and at 1 - 1.5 turns out it cleared up the roughness and got rid of the smoke.  Time for another test ride.

Day two test ride. Started first kick on the choke and run well.  Took a minute to clear its throat and then we were away.  I gave it a half arsed attempt at final run in but it was good enough for me and i started opening up.  Bike now rips.  Still needs some jetting but getting there.  In first it can sound like four stroke valve bounce when i rev it hard sometimes.  The suspension is great and really handled the whoops and sand.  I have not hit any jumps yet so my forks only showed im using about 7 inches of the 12.  I may have to take a whisker of oil out of the forks if i cant get full compression.  Photo 3 shows the tracks im running.  They are all whooped out everywhere.  On the long fire tracks i could get 6th gear wide open on the whoops and the bike felt really stable.  Fourth photo is when i noticed radiator fluid coming out the overflow.  It wasnt steaming, it was just coming out.  I headed back to the car with another 30 minutes of testing done.  The rad needed 350ml of fluid when i got home. I'm not sure if i had the cap on tight. I will take my genuine cap and some fluid out with me next time.

Brakes have bedded in and i have now used up all my adjustments.  So i have to pull the levers off at the hubs and move them a couple of notches.  Bike now needs checking over, tightening everything and getting ready for another run.



Cheers,
Alex

[mainline]

Sounds like a good time was had.  I hope you told someone where you were going, that looks a long way from nowhere if you were laying around waiting for someone to come and pick you up off the ground.

[80-85 husky]

Go Pro Go Pro Go Pro.... rev that sucker
would luurrvve to hear it humming

[alexbrown64]

Mainline, i ride with a bumbag that has a mobile phone in it.  That area is only 5 minutes from home....  I remember when i was a kid, i used to go out on my yz80 in the evening and ride until dark.. sometimes running out of petrol in the bush... i would push it home and mum would just look at me and go "alright, have a nice time?"
Husky, i have a Go Pro.  When i get the old girl sorted and find a decent track and get some practice in, i will post up a video of the 125 screaming its head off for a lap...
Cheers,
Alex

[mainline]

Mainline, i ride with a bumbag that has a mobile phone in it.  That area is only 5 minutes from home....  I remember when i was a kid, i used to go out on my yz80 in the evening and ride until dark.. sometimes running out of petrol in the bush... i would push it home and mum would just look at me and go "alright, have a nice time?"

Funny how things change isn't it .  I used to roll my cr80 down the road till i got to the park then try and ride sedately along the creekline to the bush where we rode. My parents would not have had a clue where i was, who i was with or how i was getting home. These days i am almost ready to attach a.tracking device to my 10 yr old. The world we live in?

[alexbrown64]

I have the DLS front brake and Lechien numbers to finish off the tribute bike.  I am also getting a replica Yamaha jersey from the era to go with it.  Almost done....  a few more rides needed to iron out the bugs......

But!, i am a glutten for punishment and have another project under way with its brother, the Oz version.  I am doing this one on the cheap, to be used as a practice bike and bush hack... but it is still costing a bit.  I painted the frame myself using epoxy enamel but i am going to take it to the powder coaters for a more durable finish.
I am on the lookout for a good condition original exhaust pipe if any one has one.  At great expense, i purchased a pipe from the US and on closer inspection it is for an 84 L model.  They look very close and would fit OK, but it niggles me.



Cheers,
Alex

[Ekka]

Looks like the bug has bitten you good