KTy

Okay, I got it rigth then :) Thanks Luccio and thanks Olli-ETS for the patent So, why not do that on other pistons ?? It seems on GS piston you only have to drill the holes, it is already "prepared"...

Can someone just tell me what is this "CVF-Löcher" on the piston that seems to improve so much the output power ?? If it is what I think (holes on the sides of the piston to prevent gaz from staying under the piston head), then why not do that on Polini or GS piston ??

Is this an adapted version for smaller cylinder or just the one made from the newer kit from Mathias that will include a machined slip joint ?? Anyway, beautiful power curve Gerhard !!! :-D

So cool to see all these new things in the last few months !! We are so spoiled !! This cylinder looks really impressive...

Okay then ;)

Milling on the airbox side is acceptable even though it would be much better to come up with a simpler solution... I'm pretty sure you can fit the reed system in a 5mm-thick spacer...

I guess this is what I am looking for: http://www.germanscooterforum.de/index.php...st&p=282204

Exactly ! Check the updated drawing... I have put some angle, it's not much, but it's better than nothing !

Yup, that's what I want to do... This is probably simpler and should do the trick...

Here you go... View from the bottom... The drawing is far from perfect bu basicaly the idea is that the reed(s) can bend into the existing admission window...

Very nice ! But as my engine is "stock", no high-end performance, I was thinking about something very thin, with one or two horizontal reeds, should be feasable in less than 10mm ! I am not looking for pure performances, I just want a better permitivity for the rotative valve admission system ! I will try to draw something...

Unfortunatly no... low-mid to high rpm the engine is just very good ! Besides that, I drove 200-300km, I doubt the rings would have survived if I had reversed the piston !

No better luck... I even tried with a new SI24/24 carb, with the good jets, still very weak at low rpm...

I have rebuilt my PX125E engine, since then, I have very few power at low rpm... I have re-wired the stator, I have changed for a new SI24/24, ... nothing... I cannot have it work good at low rpm, it simply lacks power !! So, I am starting to remember that the crankshaft that I changed was maybe not very well appropriate considering that the admission window on the case was not in excellent shape... On one side, the crank cheek is not striped but it is not clean either, and on the other side, the aluminum crank case admission has one little stripe... All in all, I think the rotative valve is not working anymore... So, the plan is to build a very simple reed valve system, like the LML one and to put it just below the carb... Does anyone ever investigate this ? I do not want to machine my engine cases as it is my daily rider, I just want to work out something with the carb and the air box... Mfg, KTy

Thanks for clarifying

It has probably been asked, I thougth it was, but now I have a doubt... Can you mount Franz on a primavera frame with a glovebox ?

Rigth, and I am starting learning German

Humkay, if someone proposes his soldering service to build a Franz-t, please let me know...

Now that you can buy Franz like at IKEA ( http://www.worb5.com/shop_de/d_V2003084_Fr...llframe5176.htm ), I was wondering, what tool do I need to roll up the sheet of metal ? And what kind of soldering-tool should I use ?

Yup, I'll try another atomizer !

There is two versions of SI20/20D... An "old" one than comes on Sprint for example as a mixture screw that looks like a normal "screw". Newer SI20/20D (PX Lusso for example) has this kind of screw and this is logical: They have an electric-start ! Anyway, maybe I'm a bit confused with dellorto PHB series that have a little washer and an o-ring. (Parts 19 to 22 here) Could an old exhaust gives the same results ? (low power at low rpm and normal power over mid-rpm ??)

On my SI20/20D, I have this kind of mixture screw: I was wondering if there is an O-ring... ? I'm going to check the ignition... :-D

I have rebuilt my PX 125 Arco (=Lusso), changing almost everything, bearings, oil seals, ...etc I have very very few power at low rpm, and then, around 3000rpm it is fine. For example, in 1st gear (!!), if I instantly open full throttle then it will take maybe 2-3s to really start pushing ! I have an idea on what is going on... But I hope I do not have to open the engine again... Because I had to change my crankshaft, I put an original piaggio, in good condition, BUT home-made cut (16mm). Could it be the problem ? If so, how can I change the jetting so that it works fine at low rpm ? I have standard jetting: idle 140/45 and main 140/BE5/100 ... By the way, is there a toric seal on the mixture screw of a standard SI20/20D ? I thought there were one... If it is not the problem, what could it be ?? Thanks...

Nop, I will !