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Discussion Starter · #21 ·
Ok back to the transmission the biggest problem with the Box roller chain transmission is they are no longer available anywhere if it breaks some other transmission would have to be sorced for me I think that would be the pocket dirt bike transmission but I don't know I will cross that road if it ever comes up.

With that said I know what breaks it and that thing is letting off the throttle and slamming it back on again it can take it for a bit but eventually the roller chain will snap or the primary gear reduction will strip.

Now there is no sense in moding the engine and leaving that nasty motor oil in the primary reduction so that's easy enough to drain. But the secondary roller chain section has Gross 馃あ paraffin grease and possibly 100cc of oil someone might have added in there because they didn't know about the grease and figured it was empty so they put the oil in. ( Yes the Chinese used this to trick people into thinking it's a 100cc engine).

The mod involves opening it up scooping out the grease cleaning it out with carburetor cleaner making a gasket sealing it up and adding 1/2 cup of motor oil or transmission fluid I will be adding 10w30 and a tablespoon of Lucas oil additive ( because it's what I have ) I recommend ATF with Lucas oil additive.

BTW the gear reduction side takes 1oz of 10w30

Here are some pictures of the process
 

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Discussion Starter · #25 ·
Well it runs but not right at all I took the carburetor apart and found the screen completely cloged and the flappers stuck this is typical when somebody leaves fuel in the tank and carburetor.

Basically disassembling these carburetors to clean them out is a 50/50 shot if the gaskets tear or rip then the carburetor will need to be replaced I got lucky on mine and was able to get it apart without damaging any of the gaskets.

Check out that completely blocked screen when this happens you will be able to prime the carburetor up and start the engine but it will only run for a few seconds because the pump is not strong enough to pull fuel through the cloged screen.
 

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Discussion Starter · #26 · (Edited)
Here are some pictures and a video of the bike mostly back together short of a few details brake levers and a few other things 馃榾

 

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Discussion Starter · #28 ·
I also ported the cylinder and widened the exhaust port nothing crazy just a little bit base gasket delete starter delete I downsized the cylinder from a 44mm to a 40mm to lose the decompression notch and give the engine more RPMs
 

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Discussion Starter · #31 ·
I got my spare carburetor kit in the mail today check it out.

It came with a genuine POWER spark plug I can tell it's genuine because the packaging is 3D reflective also giving the spark plug the ability to have even more power than it would normally have 馃槀
Automotive lighting Material property Audio equipment Gas Spark plug

Seriously though the spark plug is made kind of lopsided and the electrode is not perfectly center more than likely giving it the ability to snap off at the least opportune time and destroy my engine just do yourself a favor and don't use these knock off plugs...

It came with some cool stuff the thing for the gas tank some extra primer bulbs the gasket that gets all gooey when it comes in contact with gas.
Font Rim Machine Gas Automotive wheel system

Luckily I can pull out the rubber plug and get to the LSN adjustment .
Hand Watch Automotive tire Flash photography Finger
 

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