BWSP four valves cylinder head for Yamaha engine BWS125 CYGNUS125 RUCKUS 

Hello... This is from the Philippines... A huge fan of your engine modifications...

Core from this huge is a monster

Good

Is this like a clone of a wave head?

I'm looking to build a gy6, possibly convert to 4v,. What is the power of the 4v 150-171cc ? I would like around 20hp and stay below 10k rpm, I have a 139qmb, with 50mm bore, ported head, a9 cam, exhaust, ported intake, 20mm carb, it has hit around 10,200 rpm, but is seriously lacking, although better than stock, a gy6 150cc swap maybe what I need, I'm hoping to add a bit of boost, after getting it running properly, it's not a racer, but I'm heavy, and there is alot of hills here, in the foothills of NC, it's under 800' sea level , so the lack of o2 isn't a issue, but adding atmosphere can't hurt! Unless it does! If it's balanced and kept below valve floating engine speeds, it should be ok! Something in the 171-200cc range, a 32mm carb, or EFI, (I don't really want EFI), but I'm power hungry, and hate being passed, I guess that's why I need more than the 81cc gy6 scooter ! If I can get 5-50 mph in decent time, with 60-65 top speed on flats, I'd be ok with that ( for a minute haha) I'd definitely be looking to add a cylinder, or boost, something, but the kicker is,,, I need it to look like a 50cc scooter, I can stamp the 157qmj, with 139qmb, and those who don't know will think it's stock! The two cylinder mods seem to work, I'm just curious about the longevity, will it last? I'd like to build one with stroker cranks, and big bore kits, and big valve heads! And make A12 cams, maybe a9's or something better if possible! Being a small engine, I can afford to run 98-100 octane fuel, without boost, getting the compression ratio to around 200+/- psi, should make it go! Or around 155or so, with 7-14psi boost, should be ok, if the timing is ok, I'm more experienced with high performance v8 engines, and some motorcycle engines, theses lil scooter engines are so simple! And fun to work on, being Chinese, you better like working on them! If I had access to a machine shop, or a mill and welder, I could do some crazy mods, get done real power from these things, I wonder how they would run on a bit of nitro!

Could I run with a 66mm piston?

very disappointed, the cost of transport to Brazil is very high, and after you arrive here there are government fees. I was going to buy it on Aliexpress

RS100

在中国内地 开工作室？