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What does it take to up the compression on pw50

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I know there's things are really low compression stock and I know it's not a race bike. I am wondering though if it's a simple head cutting I'd still be interested in doing that. Thanks

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You can mill the head or deck the barrel.

The barrel takes out a cylindrical segment while the head is a cone. IE, the head is less volume than the barrel.

You can simply use a soda can as a head gasket, or copper spray in place of a head gasket if you are only running for a short period of time.

You can use a thinner base gasket which will also retard the timing - be aware that it's changing several dynamics at one.

But before you do any of that, I'd like to know why you want to increase the compression?

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I just figured for the simplicity of milling the head that I would bump it up some. Just give it a tad more punch.

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Beyond removing the exhaust washer and possibly swapping in the QT50 gearing, there isn't much of a point in modifying it. Some guys will put a YT60 top end in, it's a simple upgrade which is reversible a minimal cost.

IMHO, once your child is looking like he's outgrowing the PW50, it's time to start searching for his next bike. XR50 then PW80 are the next steps up many people take.

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How do you do the gearing change? That really what I want is for it take off better. I don't know how to adjust the clutch either. I know it's just a50 regardless and I'm not going to change the piston but I'd like a little more out of it.

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I've never owned a PW50, nor done the swap, but here's what I got after a quick search:

here is what you need:

- qt50 rear end complete with ring and pinion gear.

- pw50 rear axle, can come from a spare rear end.

pull the qt50 ring gear with axle in it. press the qt50 axle out of the ring gear. THEN press out the axle to the pw50, or use a PW50 axle and press it into the QT50 ring gear. then reassemble.

the rear ends are the same, but the qt50 axle is about an inch short, so that is why you need the pw50 axle.

you will lose a little top end with the qt50 gear, but you will gain a lot of bottom end.

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