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Hi guys, well we finally got the 150cc motor mounted in a new 50cc frame, this one is for one of our customers and he wanted a 235 Fatty rear tire kit with the engine swap. We are not completely done, but I thought I would at least post a few photos.

Sand the pads and bell with emery cloth or coarse sandpaper. Then apply this:



It's boric acid. Apply it in the clutch bell and on the pads. If this doesn't work you may need a new clutch asembly.

budvoss, that engine model number is different, I have not seen one of those, just do some measurements as sprocket suggested.

If your head height and bolt spacing is different to the photos I just posted, then you will have to find a different setup. Let's see what your measurements come out to.

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Maybe I am missing something here but on my P157QMJ & all the other ones we work on and build the regular head works just fine, my cam chain is the stock size. Now agreed when you use a BB kit you want to go to a BB head as well otherwise the combustion chamber is too small.

By the way what is the make and name of this scoot in question?

Most of the motors we work on are the 1P57QMJ, I have not found those to have the taller cylinder. My personal scooter has a 1P57QMJ and it takes the stock everything, I have a 63mm kit on mine.

Now the motors that have a two bolt valve cover, some of these have a different cylinder, if you have a two bolt valve cover, then measure the cylinder bolts diagonally, if they are 3" then the stock sizes apply, if it is 3.25, then that is a different cylinder and harder to find.

I have also found the scooters made by QJ (Quing Jang), Keeway, I think the UM Matrix, and there are a few others, also have the different motor with a different bolt pattern and taller cylinder. About 18 months ago I worked on this Keeway with the weird motor, It looks like that motor number is KW158QMJ it had the odd bolt pattern for the cylinder, it also had a longer timing
chain, the bore was 57.5mm, the crank was also different.

It gets really confusing, but again I have not found the 1P57QMJ to be a problem, If you want to do the 63mm (180) kit we have the cases that are already bored out.

I hope this helps, all the input from everybody is helpful when it comes to this issue.

I have a nice 63mm kit with ceramic coated piston, the stud spacing is 3" diagonal.

I also have pre bored out cases for the big bore kits, in long or short case