I can attest to the difference in the exhausts personally. I recently aquired distributorship for the LeoVinci's, and couldn't wait to get one installed. I have an old 78 Puch that has been sitting around for God knows how long, I bought it from a friend about 6 months ago, not knowing if it ran or not, but just sat it aside. I finally was able to locate these exhausts, I have been in search of them for about 2 years, when another mopedeer sent me a pic to place on my web site, with this killer pipe on it. He said he got it in Holland where he lived, and I tried forever to get a buddy of mine in Holland to send me one, to no avail. 3 weeks ago, I got my first shipment in, and immediately took one to that junker in the garage. I got the ped started with about 15 minutes of tinkering, and ran it around the block, stock. Was surprised it ran so well. Then, I pulled back into the driveway, dropped the stock pipe, and proceeded to "try" and install the LeoVinci. For some reason, this exhaust was not designed exactly to specs. There are a couple flaws with the Puch LeoVinci, to where it wouldn't fit just right. I started to lose patients with it, and decided to just start whacking at it where the problems arose, intul I actually got it to mount correctly. (will give the details at the end). I fired that moped up, and talk about quiet, but really an awesome "ping" to it. (not a bad ping!) I jumped on the moped, and started off around the corner. Seemed about normal on take off, maybe a bit more peppier, but man, when I got to the midrange in the power band, this thing wanted to take off from under me! I was so shocked at the additional power this exhaust provided, especially on a completely stock moped! Quite impressed! One thing though, (other than the mounting problems), the thing seemed to get really hot, seriously hot. Now I haven't spent any time on the moped at all previously to the excitement of the shipment that arrived, so maybe a tune up or putting actual ATF fluid in the tranny, (used 2-stroke just to get it running, out of ATF at the moment) may relieve the heat problem. I cant wait now to get this thing installed on my "SuperPed", 70cc kit, 17mm Bing carb, and 63mph at the moment. It's at a friends though, and haven't been up there to check it out to see what it'll do for that thing. I can only imagine.
Now, for the mounting problems.... (For Puch's only that I know of, haven't sold any others yet, but getting inquiries. I will ask anyone that orders LeoVinci's for other models, to have them email me with their findings of performance, and I will be posting an info page on each of the models as I hear from them.
Mounting problems for Puch... (Stock cylinder, unsure yet for the speed kits)
1. The flange on the manifold that mounts to the exhaust port is a bit too large. I had to break off the rear middle fin on the cylinder to get it to fit the port. (My other peds I will grind down the flange itself, it's only a small amount to remove to make it fit)
2. Mounting bracket. LeoVinci has added an additional mounting bracket on the pipe to give it more strength (For the Puch Model). It is welded to the top right of the chamber, and is "supposed" to bolt to the lower right clutch cover screw. Well, it doesn't even get close to coming out of the side of the moped, it hits under the crankcase, therefore also not allowing the flange to seat properly on the cylinder. I took the old magical tool, a hammer, and pounded the hell out of it until it was completely flat. Did the trick, however, it looks a bit wierd having this piece of folded metal on the top of the chamber. Didn't hurt the pipe at all, just it's appearance.
3. The kickstand. Basicaly, when you put the kickstand down, it WILL hit the exhaust, and quite a bit I might add. It actually pushes the exhaust away from the moped about an inch, which is probably not good on the exhaust studs. It does go down, but it has to be forced. Haven't come up with a solution on this yet, unless you just dont care about the kickstand, then it can be removed.
4. Pedals. The exhaust is actually a 2 part system, for the Puch model. The chamber, and the muffler, normally termed "Racing Cans" for the crotchrocket/rice burners. The left pedal of the Puch, may hit the muffler at the mounting bracket at the rear of the moped. (the mounting area for the regular exhaust) Now, I may have a bent pedal arm on the left side, haven't taken the time to replace the pedal arm to see if that is the only problem. If it still hits, then the pedals can be removed, but then it is no longer considered a moped, by law, in Florida. Not sure about other states. As soon as I do so, I will place this same info on my site at puch.net to explain where the faults are with this exhaust.
The next morning, I got on the phone with Leo Vinci to explain my difficulties with the installation. Basically, they said, sorry, we can cancel your other orders that I placed with them. I told them that I have been replying for 2 years to mopedeers that have inquired about these, and that I can sell the "hell" out of them, after I saw what this pipe can do. I asked if there was anythign I can do to go directly to the factory, to make a complaint, or at least a request to make the changes so the pipe would fit the way it is supposed to. Their comment was the dies are made, and they wont go out of their way to make these changes, it would cost them too much. I couldn't even get them to stop adding the additional mounting bracket that is useless anyway, and seems to be added after the main portion of the chamber has been made.
So, all in all, it's a great pipe. I am glad I didn't give up on my hunt for the past 2 years. I may not be able to sell any to the public, (and again, this is not a sales pitch, only for the public's info) but I will personally keep the 3 I originally ordered, and the 2 that are on the way from Italy now, if I have to. I have about 5 Puchs anyway, and will no longer even think of the BiTurbo again. I was never fond of the BiTurbo performance, at least not until I ripped out most of the glass packing in the muffler, and added additional exhaust escape holes to the end cap. More noise, but it gave a little better performance.
For future updates and findings on these exhaust systems, feel free to stop by www.puch.net and look around for LeoVinci info in the Parts Shoppe.
Sorry for the winded explanation, just thought this might be useful info if you don't want to make any modifications to the pipe or moped.