GY6 JL1P57F Question
 

I do some research and found this engine have different parts and some dimension that the average GY6 engine(157QMJ). The valve cover of my engine have 4 bolt.

My question is, What parts of the normal GY6 i can use in my engine and which not?

Thanks

with a 4 bolt cover and 157qmj
all normal mods will work including big bore
and strocker kits

For some of the bore kits, you actually need to pull all the guts out of the case and widen the bore that the sleeve needs to go into. Maybe Tom and SYCPowerSports can chime in. He does these a lot.

The 157QMJ gy6 engine is the most common engine in use in buggies and scooters. There are several other type of the gy6. The one's with the 2 bolt valve cover use a different head, cylinder, crank shaft and on some different cam which will not work in the QMJ series. The JL1P57F model you mentioned in the subject line I do not recognise. Some GY6 models were water cooled and some models have a longer case which will not fit our buggies even though they look the same there are differences. If your engine is the 157QMJ you have a large choice of parts available for it. From big bores and stroker cranks to 4 valve heads and several size camshafts. What brand buggy do you have. TOM

Hi everyone.
Tom my buggy is a roketa 150cc and the info that i put in the firts massage was of my buggy.

Here are some pics

The first 3 pictures are of my buggy and the last one is my brother sand viper 1100cc.

Thanks for the replies.

The roketa currently uses 3 different GY6 engines in their buggies. This is is because roketa had purchased sunl and another company for which I do not recal. As stated previously I am not familar with your model. One thing you should do is to pull your valve cover and measure diagnoly (top left to bottom right) the studs that secure the top end to the case. Center to center it should be (again measuring diagonaly ) 3". If you get this measurment the cam, big bore ect will work. From what I can tell from your pictures it does not look like the tall sunl type head and that is a plus. TOM

Tom...

I removed the valve cover and measured the diagonal distance of the nuts that secure the cam and the distance was 3".

Thats a good sighn, your engine will accept the many upgrades available for the GY6 engine. One of the other engines they use the stud spread is 3 1/8" whigh will not accept the big bore kits and also the head is taller using differant valves and rockers to where the performance cam will not fit it, however on some of those engines the cams did fit but the performance was not like that of the normal gy6 due to the differant angle of the valves and the difference in rocker arm ratio. TOM