New Member Big Bore Stroker Question

[dirtrider1219]

Hello everyone I just joined and this is my first post. I am a huge scooter fanatic on the quest for more power The problem is I have a 1p52qmi. I know the 1p52's (125cc) and the 1p57's (150cc) are the same besides the cylinder. All the reading I've done says that the difference with the p is in the head. Well if I buy this kit, won't it work since it basically replaces everything from the bottom up?
http://www.ebay.com/itm/SCOOTER-150C...RTqXpj&vxp=mtr

Also, he says that it does not require a spacer. A +6mm stroke is alot to have no spacer no? Is all of that clearance cut out of the piston? The guy's feedback isn't too great so I'm a little weary

[Irish]

Originally Posted by dirtrider1219

Hello everyone I just joined and this is my first post. I am a huge scooter fanatic on the quest for more power The problem is I have a 1p52qmi. I know the 1p52's (125cc) and the 1p57's (150cc) are the same besides the cylinder. All the reading I've done says that the difference with the p is in the head. Well if I buy this kit, won't it work since it basically replaces everything from the bottom up?
http://www.ebay.com/itm/SCOOTER-150C...RTqXpj&vxp=mtr

Also, he says that it does not require a spacer. A +6mm stroke is alot to have no spacer no? Is all of that clearance cut out of the piston? The guy's feedback isn't too great so I'm a little weary

I'm far from a scooter expert but an engine is an engine! A spacer might put you back to where you are now! A spacer might be defeating the purpose of the kit! Plan on high compression. I won't go thru the whole process of what I used to do when I "souped up" engines for motorcycles but you should be able to measure! Irish

[dirtrider1219]

Thanks for the reply Irish. I know a spacer would lower the compression and give me valve clearance, but I'm not sure what you men by "put me back where i am now". I'm still getting the extra displacement from the longer stroke, around 20cc's I think with the 63mm bore.

[Irish]

Originally Posted by dirtrider1219

Thanks for the reply Irish. I know a spacer would lower the compression and give me valve clearance, but I'm not sure what you men by "put me back where i am now". I'm still getting the extra displacement from the longer stroke, around 20cc's I think with the 63mm bore.

By " put you back where you are now" I mean that the spacer will make the displacement What it was before! could be wrong. Its hardtop put into words what you mean to someone else. If you put a spacer in , you're defeating the kit & making the displacement what it was to start with! Do what you want. We're looking at things differently! Irish
P.S 0.63mm is only 0.02480 in

[taz001]

Dirtrider. Irish, where did you come up with the .63 mm number? Kinda hit it sideways with that one. With a spacer, the compression ratio will drop, but you do still get to keep the increased displacement. without the spacer the piston is likely to hit the bottom of the head. As for working with your engine, I can't say. All these chinese manufacturers have their own designs I think. Based on the same honda design.

[blueboy5000]

Yes that kit will work fine w your 1p52. Not it does not require a spacer.

[Irish]

Originally Posted by taz001

Dirtrider. Irish, where did you come up with the .63 mm number? Kinda hit it sideways with that one. With a spacer, the compression ratio will drop, but you do still get to keep the increased displacement. without the spacer the piston is likely to hit the bottom of the head. As for working with your engine, I can't say. All these chinese manufacturers have their own designs I think. Based on the same honda design.

I got the # from the World Wide Metric Website. It gives all conversions in all measurements. I could be wrong. I just quoting the website. When I built an engine , I used to put it in an engine stand , put clay on the tops of the pistons( in case of an over rev.), turn it over & look for any marks in the clay. If none , I would put in a Head Gasket & assemble. Long procedure but better than ruining parts! Irish