Nice project! The crankcase damage in this engine occured because the owner didnt pay that much attention to the condition of the chain and sprockets, I recommend you changing the drivetrain from 428 to 520 for better strenght(just look for DT200R chain and sprockets, everything will fit bolt-on) and also use the chain lower guide(new avaible to buy cheap at yamaha dealer) in good condition, if you do that there will be no more problems with chain causing damage to the crankcases.
I raced the guy on that DT200R in 2016, it was only amateur cross-country type of championship but the WR200 turned out to be superior to DT :face_with_stuck-out_tongue: , 2 years later he sold me the bike.
Heres a pic of that DT, looked better than when i got her.

Lately I've been rebuilding brakes, currently waiting for the front & rear brake pump rebuild kits:

Hello,
I guess its time to show the best one of my bikes.
I bought her in '15, its an US-import bike.
She was sitting for a long time, I guess because of the broken clutch basket and worn out nicasil, but the bike was really in good condition, not modified and never taken apart, even tho there was few missing things.
I took care of the basic stuff and took part in the amateur cross-country championships in '16 and '17. I was 3rd both times in the "Junior" class (max driver age 21). Only the 2-stroke 250s were faster. The second event was very muddy and the WR got really beaten up. Clutch was totally gone about 100m before the finish line but thanks to help of my friend I was able to push the bike thru and finish the race. After that the WR got a complete rebuild and was ridden casually around the local terrains. Last year I took her apart partially once again to do the things I didnt do before, that was shock rebuilt, removing the dents from the FMF pipe, installing a slightly ported cylinder with a new sleeve and a Wossner piston and many smaller things. Today I fired her up for the first time but she needs adjustments, especially finding out the main jet setting. Generally I want to keep her looking as close to the original as possible, only modifications are: handlebars, exhaust, front springs from a '89 YZ250 and Boyesen reeds. Im kind of the oem-look freak and I love buying NOS parts, so she will stay this way. Now its time for the pics:

Thats how she looked in the ad

First ride

With her older sister

2016 Cross country amateur championships

2017 Cross-country amateur championship

After the clutch went bad

During the rebuild

After the rebuild

First ride

The power valve patent that is installed right now

High-quality sleeve

Some of the NOS parts I have laying around

Short vid from last year

Its been some time since last update, but the WR is running as always. Lately I've been riding with two old-yamaha gearheads and it was fun! You can check 3 movies we made on my yt channel -> https://www.youtube.com/channel/UCRVcP2LzhKi6GqQKIhwrAhg

And of course I noticed a lot of differences while riding on the YZ, either 125 or 250 when compared to the WR200. Both of them vibrate a lot, but thats normal as they dont have the balancer shaft. The 250 is hard to start, it really has high compression(never tried starting the 500cc 2t, that'd be a challenge!) and they both stall easier when riding with low engine speed. The 250 has a lot of bottom end power, the 125 is all about the top end power.
While the WR200 is all about the mid-range(on fmf exhaust). Its very easy to ride compared to the YZ's, easy to start and just roll on the idle between the trees. Its a very user-friendly bike. Of course it doesnt have the power of 250 or even YZ125 as the peak power Im sure is better in the YZ. Of course Ive been riding almost only on my WR for the past 4 years so its a different thing when you jump on a bike you dont know at all and ride for 10 minutes. All of them are awesome, just very different.

And last week we all went to the same old cross-country championship race where I was making my first steps on the WR. It was cold, it was wet and it was muddy. But it was AWESOME!

And I went home with the 3rd place trophy. Its a funny thing - 3 times I started in this race and every time I was 3rd, no matter the class or how many people were starting at that time

Here are all my trophies so far:

And you can check out this vid from the race, you probably wont understand much, but the WR is in 1:49 and 10:56
https://youtu.be/QERZncGW_dg

Adding some recent pics And a short movie (click)

@nottsbiker I still have it, just pulled it off the .co.uk because of brexit and plane travel ban

Been riding a bit on the WR this weekend - its hard. No matter how well I dress its still cold, its even hard to start and warm the bike - it doesnt have a thermostate so it takes a lot of time when its -15*C outside. But it was still fun, tried to do some sideways action

And, as always there is a short video:
https://youtu.be/YRDS9X1Jg7s

So here it is, the hillbilly supermoto setup:

I totally love this bike

I have the front 17 wheel done:

And I will be using rear wheel from WR125X that fits bolt-on. Now Im saving money for the tires

@valtteri

I installed this wire, its somewhere in the middle of the bike(under the seat) and the cut-out was gone. I dont know if it will help you, but I had 3RM-00 CDI and it was the older style of a DT but this little mod fixed it. You might have a different wiring loom since you have a newer style of a DT, but Im just posting here what helped me with getting rid of this problem. Anyway there is a solution to that problem.

If it sounds like this
https://www.youtube.com/watch?v=90BbYwkOnFs
then its an electronic cut-out rpm

@nottsbiker Yeah I know exactly how it feels like, waiting for some awesome packages at the moment myself, and latest snow storms are probably gonna impact the delivery time here

@nottsbiker I wouldnt worry at this point. Last package I sent to UK using primary post office took 12 days to be delivered. There was 10 days with no update in tracking and then new information popped up that the item was already in UK and was delivered on the next day. Thats just how this post office works. If it was held on customs you would probably see an update about that. Again no worries at this point.

@calum https://www.ebay.co.uk/itm/KAWASAKI-KH125-1990-barn-find-restoration-project-non-runner-with-V5-12-500-mls-/114531394831?hash=item1aaa9a650f%3Ag%3A700AAOSwuqNfuAdL&nma=true&si=jMGOJIV7i8bZiRqAsP0PcF%2Bi%2Bs4%3D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557
they sometimes pop up, but I dont consider it being a great bike

@calum not really, it was late 80s-early 90s model, brought back from a scrapyard. Not worth much

@stevie-wonder damn, I remember riding a Kawasaki KH125K with my first gf on the back when the rear tire tube blew out suddenly at about 70-80kmh. Just immidiately lost all the pressure. The rim left a loong skid mark on the road(we were going sideways after it blew out). Had to sell that bike after that, she was so traumatized! hahah
Good old times

@stevie-wonder thats an interestesting story, I dont know anything about these 80cc machines, but I had a nice time reading and looking at yours!

@nottsbiker I still have it, just pulled it off the .co.uk because of brexit and plane travel ban

Been riding a bit on the WR this weekend - its hard. No matter how well I dress its still cold, its even hard to start and warm the bike - it doesnt have a thermostate so it takes a lot of time when its -15*C outside. But it was still fun, tried to do some sideways action

And, as always there is a short video:
https://youtu.be/YRDS9X1Jg7s

@nottsbiker was it you asking about the coolant tank on facebook group? I sent you the link to ebay item, what was wrong with it?

@donaldmendez nice story, would be nice to see the result here

@calum just bought a used one, will be waiting until it gets here. Do you remember what examples of engine are in the book? TZR250? generally any 90s yamaha engines?

I would like to learn more about the 2 stroke engines, wondering if any of you know any places where I could really get to know the details about building them. Im not talking only about porting, just generally about two strokes, how does the angle of the channels in the cylinder influences the general performance? What about the shape of cylinder head? How can you set ("jet") your engine by changing piston-cylinder clearence? What are the exact differences between forged and usual pistons and how does the amount of silicon in them affect the engine?
These are some of the questions Id like to know the answer to + many more. Me myself have been struggling with stuttering of my WR200 engine on the very top range of revs - still dont have no idea what to do about it.
Im asking because the two stroke guru in my coutry is offering trainings for mechanics but the thing is they are very expensive and very far away. The only thing I found are some very old books with examples from another era. And it seems like the current proffesional two stroke guys dont really want to share their knowledge.