Oil leak after 61mm big bore upgrade??!!!

[James2132]

I just installed a ncy 61mm kit and now I have oil leaks coming from the tensioner and the crankcase. I install a ncy decompression kit and I still have the same problem although it did help. What do i do??? I thought my taotao 150cc scooter could handle the extra cc's of my big bore Kit.

[James2132]

Help someone. I'm still broke down. Why is there so much pressure building up n my case. The oil really starts leaking out at around 6000-7000 rpms

[Madathlon]

I am assuming you have an GY6150 If so it is very common for ther to be oil leaks at high rpms, you need to get a dip stick relieve kit and that should lower the built up pressure and relieve you of a few of your leaks.

[James2132]

Ok i took everything apart I rearranged the piston rings and put my stock taotao 150cc head back on and so far it runs fine with no leaks. I have not had time to test drive it yet tho. The previous head was a 61mm with gold springs. When i took it apart I found out the intake valve was stuck open. How did this happen?