MOPED ARMY

Other information - if anybody has a PA50II cylinder laying around, could you measure the exhaust and transfor port locations (from cylinder top)? I do have a PA50I that I will "convert", and knowing this would help, too.

P.S. Yes, yes I know that I "should" just get a PA50II motor. Got one? I've got more time that $$ to spend, so I'll most likely just do some port work.

Does this pipe make the bike crazy loud? I would like one..I love the idea that it works with everything else stock, apeals to me a great deal....but if bike is horendously loud I will prob skip it, as is I get 30-33 mph stock with 200 lb me on it...on flats of course...

cool, I just can't decide...thanks for input!

I've been looking for a Proma pipe - but no one has it in stock, AND there is NO estimate when parts will be back in stock. It is starting to sound like the Proma pipe may be a thing of the past.

Stephen, the pipe does make the stock hobbit louder, but it becomes MUCH louder with a 70cc kit and a 21mm carb and intake. My hobbit is VERY loud at WOT compared to a stock ped.

Justin

You will have to buy the Proma Circuit pipe from Europe.

Try these sites:

www.tuningschmiede.de

www.vdhparts.nl

There are probably more. I found these by doing a Google search.

Good Luck

this is a port map i have just made

one thing, this cylinder has been lightly ported, the exhaust port has been enlarged slightly and the cylinder skirt cut outs have been enlarged slightly

hope it helps someone

ps. it is a big pic file, sorry dial-uppers

*measurements in mm

I did a port map of my stock PA50I cylinder yesterday. I found that all ports, except for the exhaust are the same.

The PA50I port starts at 32mm from top of the cylinder. The port is 7.7mm tall, and is 18.5mm wide. It is very small!!!!

In this thread is a port map from a "lightly ported" PA50II. I don't know what lightly ported means . . . ? Anyway, to the point:

The PA50II port starts at 27mm from top of the cylinder. The port is 15 mm tall, and is 30mm wide.

This means that to convert a PA50I cylinder to PA50II specs:

Raise the port 5mm.

Lower the port 2.3mm.

Widen the port by 7.3mm, or 3.65mm.

I ported my PA50I yesterday as well. I had limited tools, but got my port opened up to 13.5mm tall by 26mm wide. I could not open it up any further with the tools that I had.

The difference is worth the work. My son has not determined the top speed, as it means exceeding the local speed limits (yes, he's a good kid!). But, he does report that he can now hold 25MPH (the neighborhood speed limit) using part throttle, and hold it up the hills, too.

The only down side is that the moped is now "cold blooded". It takes about a full minute to warm up and allow full throttle operation.

No plug chops yet, but I figure that I am close (running a 78 now).

when i lightly ported my cylinder i raised the exhuast port and widened it ever so slighty, probably too much, the low end has suffered a lot...i would reccomend only going to about 28mm wide and 14mm high...even then the low end may suffer a bit