Its like you are reading my mind, I'm just fitting a 57mm mazzu crank to my malossi166 and this video came in perfect time. One question, do I need to cut my mazzu crank to extend the closing time to 70 or can I cut the rotary valve on the case?
Hey sir, i have a question about 5:47 how did you convert from mm to degree° ? you really help me understand a lot of thing & i appreciate your effort explaining all this, thanks ! -------------------------------------------------------------------------------------------------------------------------------------- ps : im working on piaggio ciao / si / bravo ( rotary valve ) My problem is i adjusted the gasket below the cylindre, because when the piston is at BDC ( ports was not fully open ), so i add 1.5mm to fix it, now the ports are fully open, but the timing is bad, after i turned the engine on, he went crazy idle & hole in acceleration, i knew it's coming from the gaskets that i add below the cylindre. now im trying to fix, i did a lot of research, im still learning but i want to be accurate. here's some info's if you cound give advise or help and thanks again. -------------------------------------------------------------------------------------------------------------------------------------- ( PIAGGIO CIAO ROTARY VALVE ) inlet open : 112° inlet close : 53° total inlet : 165° conecting rod : 78mm stroke : 43mm pbt : 3mm -------------------------------------------------------------------------------------------------------------------------------------- ( TEST 01 Gasket 1.5mm below cylindre ) Exhaust port duration : 103° - 257° = 154° Transfert port duration : 118° - 241° = 123° -------------------------------------------------------------------------------------------------------------------------------------- ( ORIGINAL GASKET 0.1 very thin gasket - ports cylindre not fully open at BDC ) exhaust port duration : 102° - 249° = 147° transfert port duration : 121° - 235° = 114°
thx. Opening ports is overrated, timings are more important las u just experienced. Better use an online calculator, there are plenty, ie this one: ddog.at/stz/rechnen.php
@@FreakMoPed8 thanks 🙏 for the reply sir, So I have to use the cylinder timing to get the the right crankcase intake timing and website you sent me will help me get that timing i guess.
for a person understands how to adjust ignition timing on 4T Scooter : it is really veryhard to understand how to adjust timing on Vespa or scooter that has no valves .. but I try to understand ..
verlängerte einlasszeit mit dem originalen zylinder macht wenig sinn, man muesste ihm zumindest den vorauslass vergrößern, dann sollte das halbwegs funktionieren. Anpassungen am block sind egal, der 200er hat eh nur 2 fake ports, 125/150 mit echten ports macht auch nichts, hats halt ein paar mehr toträume
Can't understand the logic of 112+45=157degrees. If it starts open when piston is at 43.1mm from the top cyl which is 112degrees and closes at 10mm from top cyl which is 45degrees, then the oppening time shouldn't be de difference between open to close which in my mind is 112-45=67degrees? This is freaking out my mind and can't understand where i'm thinking wrong here :)
Thanks for your master tutorial, i also how did you convert from mm to degree° ? I want to know may i looking for download datatable about strock relationship with degree (60mm.....57mm to ....degree). Have any formular? Help me! and Thanks again!
You nees forst of all 0,05mm toleramce, than you can go up to 200, with exhaustbooet widening it will peak Up to 25hp. I prefer openining intale to the back max, to the front original. But 0,05mm is the most important thing, if not provided, also short timings will cause blowback and engine will never work normally