The cyllinder is from poland, and seller said that is from final manufacturing, not from original ddr cyllinder (but the ports looks the same as original, even dimensions). And the piston quality is quite worse than original 50ccm piston that I have with stock cyllinder.
But as I said, the power is quite good, but only above cca 7000 rpm. Under that i lazy 
The sharp edges have all ports, I can smoothen then. But this stripes are all around the piston..not so much, but there are too.
OK. Its 60/2 (not from original DDR.., but from Poland), 16N1-11 (nozzle 78) with original air filter (but with microfilter from vacuum cleaner :-)). And secondary sprocket is 15.
BTW..Is this piston bad? (I think that shiny strips)...The speed is quite good (about 70 km/h), so i don't think that cyllinder is seized.
[ATTACH=CONFIG]10663[/ATTACH]
Hi again.
I shorted the exhaust elbow to 1-2 cm and drilled the two holes in the silencer like AOA (but without shorting the tailpipe) . Now, the resonance effect is between +- 7500 - 8500 rpm (from 6000). Its cool, but a little "problem" is that from 0 to +-7500 rpm the torque is too weak :(. So above 7500 rpm is the real "turbo boost" effect 
.
I thought that the torque in low rpm doesn't be sooooo weak.
Is there any possibility to get out this torque hole? (now is this: zero power, zero power...full power and I want: zero power, more power...full power)
Have the shorting the tailpipe any effect on this? Or doesn't this opening of exhaust too much for 60/2 cyllinder?
My setup is 60/2 and I have adjusted the exhaust window from 31 mm to 29 mm (and reduced cyllinder head) and my ignition timing is 1.6 mm gefore top dead center.
Or should be more on less in this setup?
Thanks!
Thank you, I will try it
Ok, thanks. I will try this modify. But I have a two last questions.
Did you mean the dimensions (18,20) which are on this image shown like 17,5mm and 22mm?
[ATTACH=CONFIG]10303[/ATTACH]
So if i understand good, I will shorten the elbow, drill the two holes in the silencer like AOA and open the tailpipe and also shorten that tailpipe to yours dimensions? (But the last thing i cant do without cutting up the last part of exhaust?)
EDIT:
To Sperbär 50:
But I don't want to buy a new exhaust
Thanks for your answer
I had the serial exhaust with the AOA1 mod. Then I bought this exhaust with 32mm elbow because the old exhaust was ugly and rusty.
So now the torque is higher, but max. power and speed is a little smaller then with modded serial exhaust.
I dont want to buy new exhaust, I want only to modify this Reso and get a little bit higher RPM (shift RPM range/resonance effect up).
Hello, I have this exhaust on my Simson (60/2) - Reso 32er Auspuff kpl. Simson S50 S51 SR50 KR51/2 * - SIMSON Ersatzteile ETHS Ersatzteil Handel Stehlik (or MZA Reso, maybe similar to A6 tuning auspuff from reichtuning.de... dont know, its from the czech shop)
Torque is nice, but i would like to move the maximum HP little bit up. Now, the resonance effect is about 6000-7500 and I want to move it a little bit up.
Can I shorten the exhaust elbow about 6-7cm (like AOA1)?
It will have the same effect and will it shift the resonance spectrum up, so I can get more HP? (as with AOA)
Thanks.
