Other 1998 KX80 Smoke, High Idle & Bubbles in Trans

Hey guys new to the forum, will introduce myself here shortly, i got a 1998 KX80 for fairly cheap, when i bought the bike it ran but lots of smoke with what looks like bubbles in the transmission fluid. This is my first 2 stroke so bare with me. I purchased both Owners Manual and also the Service manual. The smoke pointed to the Crank Seals, so while i was in the engine i replaced all bearings and seals, crank big end bearing and rod were all still in spec so i reused the crank assembly. Cleaned up the engine and put it all back together, torqued everything back to spec. Put new fluid in the trans and radiator, but when i start the bike it still smokes a fair bit and has a vary high idle for a few seconds then drops down to almost dying point. My carb is clean and jetted to spec float height is in spec ect. I also noticed that my trans fluid is still a bit bubbly and im not sure this is normal? Any help would be really aprechiated. Heres a few pics of the trans fluid, spark plug. The only thing i have not yet checked was the reeds, Piston and Rings. I know those are probably the first things i should of checked to begin with but the manual said white smoke = Crank Seals so thats what i went for first.
 

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SRAD97750

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... i replaced all bearings and seals, crank big end bearing and rod were all still in spec so i reused the crank assembly.
... The only thing i have not yet checked was the reeds, Piston and Rings.
Welcome.
I am uncertain how you split the cases and replaced the crank bearings without seeing the condition of the piston and rings?
...when i start the bike it still smokes a fair bit and has a vary high idle for a few seconds then drops down to almost dying point.
Sounds exactly how it should act. The engine shouldn't idle or stop producing smoke until at operating temperature. HOT is where all setting should be adjusted, as this is where you will be riding it.

That plug is soaked with fuel, I suggest setting the float in the carburetor and try again.-BIG DAN:thumb:
 
Welcome.
I am uncertain how you split the cases and replaced the crank bearings without seeing the condition of the piston and rings?

Sounds exactly how it should act. The engine shouldn't idle or stop producing smoke until at operating temperature. HOT is where all setting should be adjusted, as this is where you will be riding it.

That plug is soaked with fuel, I suggest setting the float in the carburetor and try again.-BIG DAN:thumb:
Thanks for the quick reply! I did look at the piston and rings i just dident bother measuring and making sure they were still in spec as that wasnt the concern at the time. The piston and rings looked fairly new. Im assuming were replaced with OEM at one point in its life, cylinder head looked good aswell surprisngly for its age I know my plug is on the rich side like ive stated this is my first 2 stroke, all my other bikes have been 4 strokes so how the 2 stroke runs and how its suppose to run is a bit different than what i am used too is all. My main concern really is the smoke, ive heard 2 strokes are suppose to but than clean up once warm, mine smokes and even when warm still smokes. I have also replaced the packing witch made a big difference but still noticable. Again im used to 4 strokes that hardly ever smoked and if they did usually it indicated somthing wrong and was corrected.
 
It's an 80cc scream machine. It lives for 12,000 rpm at all times and it's we're it needs to be run for a bit. The residual smoke you are seeing is probably from the assembly lube residing in the elbow of the pipe. It will disappear once it's up to operating temp for a 20 minute 12,000rpm MOTO.
 
It's an 80cc scream machine. It lives for 12,000 rpm at all times and it's we're it needs to be run for a bit. The residual smoke you are seeing is probably from the assembly lube residing in the elbow of the pipe. It will disappear once it's up to operating temp for a 20 minute 12,000rpm MOTO.

Makes sense, so far switching from 4 stroke to 2 stroke ive been very happy with it. I dont race, mostly just trail and field riding i know its probably odd to switch to a 2 stroke for my style of riding. but i like the extra kick the 2 stroke has compared to the 4, and the powerband is a + for wheelies and such. I may just be over concerned since its my first 2 stroke and its a new beast compared to what im use to but i suppose its better to over worry instead of running things to the ground. Ive only got probably 20 hours on the bike since purchasing it, 15 hours when i got it and another 5 after rebuilding it. I probably did the rebuild for nothing but atleast i know all the seals/gaskets and bearings are brand new and the inside is mint. More ease of mind in the long run
 
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