Team Green....Kawasaki !

So without knowing your jetting or needle clip position, once you start cutting back on the oil, you could also possibly find yourself running a little rich then as well?

What fuel do you use?
 
Yes, if you cut back on the oil and change nothing else, you have moved toward creating a richer burn during combustion because with less oil molecules there is more room for gas molecules.

- folks think that by dicking with the amount of oil in the mixture is the proper way to tune a 2-stroke combustion burn.
You have to pick your mixture and stick with it. - it should be a constant amongst all the variables that will come along with jetting.
The engine only needs so much lube - any more in the mix and it's taking away valuable space from the atoms that do the exploding.
 
Well it's been a struggle lately to get garage time to keep this project moving forward. Priorities first right?
I'll have a few extra days during the holidays so I spent tonight getting started on tools, parts and pieces ordered to have what I need to get it done.
I have also realized that I need to decide what all I am going to do to the motor and the bike, and decide on a deadline to finish because work always get's heavy starting in January, and spare time drops to little to nothing, followed by grandsons little league at end of march.
I also have work needing done on the other bikes I want to race.

I brought some parts and micrometers in the house today to get up to temp so I can start checking measurements. Plenty to come.
 
NQ I still have a front and rear wheel, forks, and a box of other stuff for the KDX if you want it. Been so long since I looked in the box I don't really remember what was in it... Not looking for anything for it but more space in my garage....

I may have told you the deal but that bike was what got me going on this whole vintage thing in the first place. I bought one, motor was junk, bought another one, made one, etc. I was a dualsport/enduro rider and thought I would really enjoy HS so I went that route. Back in 2011 you might recall the first thing you did was a lap on the moto track so after the HS I was like man I kind of liked that more. Didn't help that it was like 105 degrees and my stator was cutting out so I had to push it up hills to bumpstart it. Pretty sure I had some form of heat stroke. Hadn't raced MX since the early 90's but off I was in that direction. Sold it like a year later to some KAWI stud that had a stable of H2's, Mach III's, etc and I mean good stuff so I was stoked it went to a good home. Mine was a 1980. I really like the look of those KDX's:
KDX175 left side.JPG


And by 2013 my garage looked like this:
x (2).JPG


Putting my kid through college cured this addiction pretty quick! Down to 2 right now, looking to move back up to 3...

Let me know if you want the stuff Mike.
 
Damn.... that KDX was nice. But then again, you build your bikes close to perfection as well.

Hell yes I want the parts... haha.:D
Just let me know how and when you want to hook up.

So I'm seeing what looks like a Yamaha DT, or a variation of. (I would have hard time knowing that I let that one go).
And I recognize your Suzuki trail, I'm thinking you have kept that one. ( I had the 74 CT125, Dual range).
But tell me about the little RM125 snuggled in the middle? That sort of resembles the 76 RM125 I have in the barn.
 
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So I've been hard at it gathering stuff. I ordered a couple of Starrett machinist V-blocks for run out and alignment checks of shafts and such. I ordered a 11"X12" granite surface plate.
And I've been reading and digging hard on these JIS screwdrivers. Here's were I ended up:

I just ordered the Hozan JIS-5 screwdriver set tonight.
I really like the Vessel impact screwdrivers as well, have to add a set of those to my Get-List.

I also spent a fair amount of time hunting for a set of JIS driver bits for my hand impact tool. I had a lot more difficulty with that. There are plenty of offerings of JIS bits that are 1/4" shank, but the impact driver uses a 5/16"or 8mm shank bit. I'm always cautious buying internationally but I did find a set of three 5/16 JIS driver bits on ebay from a seller in France. I used Paypal for the transaction. Nobody stateside even offered them.
 
76 DT175 - sold it to some guy that had every 76 DT but that one at Mid-OH last year. That is actually a 75 RM125, only year with a downpipe and painfully slow. Pretty rare though. Sold it to a huge collector down south. The other is a 76 CR250 - some guy from Italy bought it. Told me while we might have had 50,000 here in the states in 76 they only had a couple thousand. He was one of those guys that loads up a container at Mid-Oh - he actually came to my house on Thursday before it to buy it. The TC is still the pitbike for me. I ride it to the store every once in a while and I always get asked about it. I actually look kind of funny on it but the open face helmet makes it work!

I could probably just let you know when I head that direction sometime. You might remember I am a sales guy so it should be in the near future. If you ever come my way let me know. I live about 2 miles from the AMA office.
 
and to think about all the screw heads I've drilled off,looks like a new tool for the toolbox in coming
 
Finally getting back to this, between last night and tonight I've now got some crank measurements.

On the crank seal grooves worn in, here's what I ended up with:

Both clutch and flywheel sides

Crankshaft diameter .....0.9825
Diameter measured in the groove....0.9800
this gives me an actual groove depth of 0.00125
IMG_3346.JPG


The other measurement I took was the crankshaft runout. The book shows setting the crank up in centering spindles which I don't have, but I believe I still got good measurements using the surface plate and V-blocks.
Here's what book shows:
IMG_3359.JPG

IMG_3361.JPG


My measurements on both sides netted me a variance of 0.001

And this was my setup:
IMG_3351.JPG


IMG_3356.JPG


IMG_3357.JPG


The book did show other measurements to take, such as "Connecting Rod Bend\twist", "Connecting Rod Big End radial clearance" and "Connecting Rod Big End side clearance", but my crank and connecting rod feel very good with no noticeable looseness anywhere. So curse my laziness, I skipped these.

The book showed a service limit measurement for the connecting rod small end to be.......0.789
This caused me to have an "oh-s**t" moment because mine measures 0.827 which is 0.038 over the service limit.

At this time I don't think I'm going to sweat about it. With a new wrist pin bearing and piston pin I think it will survive. I'm not really that interested in having the crank split at this time and I'm not rebuilding a 10,000 rpm 450 four stroke. The important thing to me is that I know about it.
I'll just be mindful of this before I launch her over any jumps, I'll make a file note on it and move on. In the meantime I'll have to begin the search for a new crank and rod.
IMG_3362.JPG
 
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So I've been hard at it gathering stuff. I ordered a couple of Starrett machinist V-blocks for run out and alignment checks of shafts and such. I ordered a 11"X12" granite surface plate.
I just ordered the Hozan JIS-5 screwdriver set tonight.

In the past there have been times that I've needed a really good flat surface for checking the trueness of things, so when this subject of the surface plate was brought up by Sharc, it rang a bell with me... need to get this. I did order one, received it and you can see it in the crankshaft pic's I just posted. Not a real expensive one, but accurate enough for my garage.

Well on a side note, this got my mouse brain wheel turning and I remembered seeing something at work a few years back that caught my eye. We have an abandoned lab that never gets used anymore. A few years ago they tore out an island work counter. They removed the bench top and just set it aside for scrap, and been setting there since. I remembered it very well. I went back and checked on it, and sure enough, still there. It's made of some sort of black material that is heavy as granite. I believe it is 1-'1/4" thick and heavy as hell. But the top is incredibly precision smooth. It's not that large and will fit perfectly on my work bench. Needless to say, I grabbed it up and got a scrap pass.

I just received the Hozan JIS screwdrivers at the house today as well. I quickly realized that I will have to do more digging and make another purchase because there is no large size screwdriver in the set.
I'll have to double check but not sure that the largest one in the set is big enough for the engine case screw heads.

Enough for tonight...ugh!
 
Too many life demands to get anymore hands-on progress in the last couple of days, but I have managed to get parts ordered and received a Rocky Mountain shipment today.
On a side note I did come across a pretty cool KDX forum: (even though Miss the Flip and I may be the only KDX racers on here :D)

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Time for a little update on where I'm at with this project.

Since my last post it bugged the s**t out of me on the issue of my connecting rod being out of spec on it's measurement. I just couldn't live with it.

So after a lot of internet searching and reading, I found a new rod set and have it ordered. The crank halves (or the Rod set) aren't available as OEM parts, and the only crank half side that I could find is the magneto (non-oil) side. Every spare minute that I have had to focus on this has been tied up on the rod and crank issues..

I did get a Tusk crank puller ordered this morning, which I badly needed during my MX250 rebuild ( which I didn't realize until afterword).
One thing about the internet, it can save you a hell of a lot of time, and can cost you as well.
So I'm still at it, and it will all be worth it when it's done.
 
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I spoke with a rebuild shop today for my crankshaft rebuild and discussed what I have.

He verified that the connecting rod that I purchased is a fit, but they have to narrow it a hair on the crank end by machining. Says that it's just one of those little forging differences you get from supplier to supplier. He seemed to know the Kawasaki cranks very well. Also talked about the lube and mix ratio that I've always ran in it. He was very happy to hear that I run Yamalube and highly recommends it.

We also discussed the crank seal grooves issue, and when I gave him the actual groove depth ( 0.00125" ) he immediately stated that I had no worries at all with that. Says that you won't begin to have issues until you are more than 0.011". He stated that sucking oil past the seals was likely more due to the seals just being old and worn. I told him that I'm pretty sure these are the original seals, first time the cases have been split and crank removed. Since 1982.....Uhhh yea, old seals, bad seals.

I do know from experience that over time, pretty much any type of rubber seals get hard, stiff and ineffective, especially when they are exposed to petroleum's. He went further to suggest that a slight form fitting groove on the crank for the seal to ride in actually gives it a better grip in preventing leakage. Nothing to worry about.

Shipped out today.
 
That thing is going to rip when you get it back together - Better than new.
Do they make a gripper seat for it?
 
Got my crankshaft back from repair shop last Friday afternoon. It turned out that the connecting rod I purchased was an exact match and they didn't have to do anything to it. (KX125 Rod).

I always learn a bunch every time I tear into my bikes like this. It's especially nice to know who to call when you have issues and I won't hesitate to use this shop again in the future. The owner seemed very knowledgeable and experienced, communicated very well with me about my crank and information about the Kawasaki's. He did a great job cleaning up and polishing the crank and rod install.
Very reasonable on price and quick turnaround.

I had a little extra time last night so began cleaning up the crank case and will begin pressing bearings and seals this week. Will be nice to get this thing back together, it's just tough with our busy schedule.

IMG_3369.JPG


IMG_3370.JPG


IMG_3372.JPG


IMG_3373.JPG
 
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