157QMJ vs 152QMI are there any differences?

[guyfromeurope]

Hi,
I Just wanted to ask if the are any differences between 157QMJ and 152QMI ? I found two big Bore kits the are sold for the GY6 engine. I own an Kymco Agility city (2016) 125cc so it should be long case, Version B ( the head studs are placed wider than on the chinese engines) Does the 157QMJ have wider head studs or is it the same like the 152QMI?

Thanks,
Julian

[rocketdogiv]

The only difference I know Guy is that the A Type is 54mm between the cylinder studs and the B Type is 57mm. There might be a difference in the cylinder height or the head height. To be honest, I'd be surprised if yours is a Type B with only it being a 125cc. Check it and see. Advertisement for parts can be very confusing,

[alindragon]

Hey did you ever find an answer to your question? I was sent a 152QMI 125cc from an ebay seller and want to know if I can put a 171cc big bore kit in it or sell it and start with a new actual 150gy6

[90GTVert]

Most 125s and 150s should be able to use the same cylinders, aside from the B variants, and they have the same stroke.

[alindragon]

I took the valve cover off and the rocker studs measure 54mm so chances are it will take the 171cc cylinder and jug. Hopefully I will not have to machine the crank case and it will slide in easy. Thanks for the confirmation.