Hello everyone! Looking for some answers if you can help!

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ScumLord

New Member
May 18, 2023
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So I’ve got a 66/80cc Chinadoll with a stock piston that I’ve windowed out like LA HoverBikes just to a curtain point I liked within the casting, a 2 inch miaowa reed valve kit and an HP carb with a 80 size jet installed. I’ve got a range of #50-85 I’ll say this as a start the bike ran pretty well getting me to 30MPH before I windowed my piston and put the reed valve on, also I have experience before working in small engines. 1 of my 4 studs will not tighten into the crankcase, causing me not to be able to tighten the head down on the final bottom left side of the head allowing air to escape when the bike is cranking pressure. My question is if I JB weld my bottom left stud back into the crankcase and get a perfect seal should that make it to where the windowed piston and reed valve will run? Of course I’ll probably have to fine tune my carb as well but I’ve gone through every jet I’ve got and from what I’ve read I shouldn’t have to go so large on the jet that I’m in the 80’s
 
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wrench

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Aug 20, 2019
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So I’ve got a 66/80cc Chinadoll with a stock piston that I’ve windowed out like LA HoverBikes just to a curtain point I liked within the casting, a 2 inch miaowa reed valve kit and an HP carb with a 80 size jet installed. I’ve got a range of #50-85 I’ll say this as a start the bike ran pretty well getting me to 30MPH before I windowed my piston and put the reed valve on, also I have experience before working in small engines. 1 of my 4 studs will not tighten into the crankcase, causing me not to be able to tighten the head down on the final bottom left side of the head allowing air to escape when the bike is cranking pressure. My question is if I JB weld my bottom left stud back into the crankcase and get a perfect seal should that make it to where the windowed piston and reed valve will run? Of course I’ll probably have to fine tune my carb as well but I’ve gone through every jet I’ve got and from what I’ve read I shouldn’t have to go so large on the jet that I’m in the 80’s
JB weld won't last long
You got a striped threaded hole in the case, Put in a Heli-coil to fix that
Heli-coil is new thread insert
 
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ScumLord

New Member
May 18, 2023
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JB weld won't last long
You got a striped threaded hole in the case, Put in a Heli-coil to fix that
Heli-coil is new thread insert
I’ll try that, I’m thinking of ordering a new crankcase just to fix it altogether but I’m afraid that it’ll just happen again lol
 

Mossy

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May 20, 2022
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Don't bottom out the stud in the holes... When it gets hot it needs a little room to expand or it will strip
 
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ScumLord

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May 18, 2023
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I really appreciate the help guys I’ll try the JB weld as a quick temporary fix and then definitely get the EZ lock kit for a long term solution.
 
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