I put an amazon top end on my sons pw, it had an amazon big bore but i wanted to bring it back down cause he was 5. So last week he was done riding, so i rode it up to the garage with me and him on it, about 100 feet. Piston came to a stop in the cylinder. Let it cool down it was fine. Now i gotta kick it a billion times to get it fired up again. Thats the condition it was in when i bought it. He has rode it probable 3 times since i did the top end, but right from the rip it sounded like it was rubbing in the cylinder. Kit was kind of junk but a complete cylinder and head that are oem are like 3 bills lol.
I'm thinking maybe faulty from factory. I've never had such liw compression using Chinese parts. Im tempted to put genuine cylinder head to see if any difference. Under 100 i wouldn't be happy or recommend using company it came from. Have a good one and stay safe bro
Good to know this is exactly why i keep oem parts!. So it sounds like oem head re-surfaced + china cylinder is the ticket 🎟
Thanks for taking the time
Hope it helps! Thank you
Little trick on all 2 stroke gaskets especially head gaskets , case and other main gaskets . Coat the gaskets in yamaha bond = zero air leaks .! .
Great stuff!
Thank you!
Thanks I just purchased a ebay cylinder and head piston kit I guess I'll reuse the original head
Perfect! Glad this helps.
I put an amazon top end on my sons pw, it had an amazon big bore but i wanted to bring it back down cause he was 5. So last week he was done riding, so i rode it up to the garage with me and him on it, about 100 feet. Piston came to a stop in the cylinder. Let it cool down it was fine. Now i gotta kick it a billion times to get it fired up again. Thats the condition it was in when i bought it. He has rode it probable 3 times since i did the top end, but right from the rip it sounded like it was rubbing in the cylinder. Kit was kind of junk but a complete cylinder and head that are oem are like 3 bills lol.
Ohh man! Ive heard of this happening. Hope it’s all good now.
I'm thinking maybe faulty from factory. I've never had such liw compression using Chinese parts. Im tempted to put genuine cylinder head to see if any difference. Under 100 i wouldn't be happy or recommend using company it came from. Have a good one and stay safe bro
Thanks for the info! The ring end gap was in spec. Seemed to have a good tight seal as well. Maybe due to the cylinder walls not being broken in yet?
I didn't think anything would start easy being under 100psi. For a rebuilt top end id expect higher
Right! I agree
Exhaust port looks very “square” in the aftermarket cylinder. Is it the video/shadow or was it ported?
It does look more square. It was not altered or ported
Hey do you know about the Yamaha 4 zinger
I don’t know anything about them. Are they a similar motor?
That cylinder looks awfully shiny. Don't you have to hone it to get the rings to seat?
It has very low hours on it. Probably the way the camera makes it appear.
I dont think my 7 year old is gonna care haha......But cool
You’ll care if it’s really hard to start though!
@@motoblast3574 but it's not.....starts 1st kick. Can make a video to prove it.....