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I thought KTM fixed everybody's bikes for free ?

Try some dish soap. Went from a stock 34mm to a 38mm on vintage Yamaha MX360. Stock intake.

Don't think the bar is wired into the circuitry ,if I recall. The YZ80 system I used had one as well. Maybe it is more of a support system for the rotor / flywheel, in order to keep things in phase. Like a chain guide. Edit: Never had much luck on mixing boxes / stators, even if the wire leads...

The 250 would have been great if they only would have made that cylinder standard, instead of optional.

Tampa Bay area. Threw the stock 79 internal system on an old 88 YZ250 I came across with no fire. Went right on. Used to spend quite a bit of time at a local salvage yard with a few pullers. Learned that many Japanese bikes share the same 3-4 tapers on the crank.

With the YZ80 system on my old 250F engine, it seemed like it would twist a few more R's than the 250 internal rotor. I was trying to get some flywheel weight on it for short track. Moose added 14 ounces to a new stock flywheel. It would twist.

250 is internal rotor. 400 external flywheel. Do the wire lead plugs match ? Plug it in and see what happens. Surely the advance curve is different between the two boxes.

Stator and flywheel ? The tapers are different . 78 started the small case 250 era, and crank ends changed as well. I fit an 87 YZ80 system on a 79 YZ250F with minor work. The 400F uses the large taper crank ends, like the 73-75 MX250-360-400 , 76-77 YZ250,and 76 to 78 YZ400. I used a 79 400F system...

Pop that little plug out so you can adjust the air screw. Your repair looks good to me. I mean ,they are a dang moped engine. And I have used those China carbs on PW's. They work / run OK.

Just tighten the piston nuts.

I believe you need to use the QT pinion gear as well. The tooth count is different on both ,if I remember. Found an old QT and robbed the diff a while back. Basically just swapped the axles. Need a press. I let that whole assembly go cheap. Seems like gold now.

Never hear much about checking out the heads much when suggestions are given. Valve seats concentric ? Valves measure out ? Springs not sacked? Stem seals and keepers good ? The power in a four stroke is made in the head. Just seems like it would come up in rebuild talk to maybe freshen the head at top end time.

Check the cam chain guides. Maybe jumped timed and bent a valve.

We all get a little squirrely sometimes. Not just on the track. Did I win ?

Should have used BB's.

Had that happen on a KX125 after it pitched the chain and wound itself around the counter shaft about a million times. Look the rest of it over good. Had mine welded. And then sold it.

Not interested in watching. That Big Cat rescue place is about five miles away from my place. Complete shit show , that place.

Got this new in 1969. Second bike ever. Still have it.

Everyone comes out on a Rick Melon replica, racing in Walmart parking lots, as no tracks or factories exist any longer.