PX200 massive blowback after rebuild!
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Member
PX200E
Joined: 01 Oct 2012
Posts: 18
Location: Philadelphia, PA
Sun Sep 22, 2019 6:06 pm quote
Rebuilt my motor with all new seals, reassembled and started fairly easily but now has a ton of blowback from the carb! Is this a wonky seal? Bad case gasket? Upside down piston?

Not looking forward to tearing it down again, but I have a good system now for jacking up the bike and setting it on jackstands that will save my back.
Addicted
GL, PK, PE200 with hack, Sears Rust Badge
Joined: 24 Apr 2012
Posts: 819
Location: Deep in the heart of Texas
Sun Sep 22, 2019 6:09 pm quote
Exhaust, stator, CDI, or rotary valve are some of the issues.

Start here. https://www.youtube.com/watch?v=OhX6zE8LmFA and https://www.youtube.com/watch?v=w8h7LKkHV4g


Good luck!
Member
PX200E
Joined: 01 Oct 2012
Posts: 18
Location: Philadelphia, PA
Sun Sep 22, 2019 6:39 pm quote
CDI, stator, and exhaust are new, hope it's not the rv! I'll investigate more tomorrow. Thanks for the refs!
Hooked
1952 Allstate 1955 Allstate 1958 lambretta 1965 Allstate 1968 sprint
Joined: 20 Jul 2017
Posts: 476
Location: Central california
Sun Sep 22, 2019 7:10 pm quote
Px200
Donít know if this makes you feel any better, but I have a p200e and it has lots of blow back. Didnít really realize it until I ran it with the air cleaner and air box removed. Iíll be honest I was concerned...put it back together...thing hauls ass. This thing has a lot of miles on it. I ride it everywhere. Not going to worry about it. I saw your video...nothing compared to mine.
Note: assuming our engines are alike. You have px200...I have a p200e.
Someone else will have to chime in and verify if they are the same or not.
Scott
Ossessionato
Joined: 26 Oct 2015
Posts: 2467

Sun Sep 22, 2019 9:28 pm quote
Are you running an air filter? Because if not, fuel is going to go all over the place.
Member
PX200E
Joined: 01 Oct 2012
Posts: 18
Location: Philadelphia, PA
Tue Sep 24, 2019 10:18 am quote
Was using mista freakmoped's advice to use some hondabond/yamabond on my gasket, turns out you should torque it down to more toward maximum value (13ft/lb). I had torqued to 10 for everything. No more blowback and sounds a treat!
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