Modern Buddy

I got a Buddy 50cc a while back and finally got round to playing with it. The guy I got it off sold it very cheap. I did get a few new things like cylinder kit and exhaust and a spare carb just to make sure.

It's never ran. I am thinking that he put 4 stroke oil in the Buddy. I know this isn't a good things but never come across it before. What kind of problems/damage would it cause? The piston was in pretty bad shape when I took it out if that's a hint.

Shouldn't cause any serious of permanent damage. Just gunk up the oiling system and a lot of carbon build up on the piston and head. 4 stroke oil is a heavier viscosity than 2 stroke oil plus it doesn't burn as well or cleanly in the combustion chamber. You'll need to flush out the 4 stroke oil from the tank, hoses, and pump then refill with the proper 2 stroke oil. There may be some residual of the 4 stroke oil in the crankcase and bearings that will slowly get flushed out as yiu ride the scooter. Keep an eye on the sparkplug to make sure it doesn't get too carbonized.

Thanks for the reply.

I will get out as much as I can but pretty happy I don't have to completely rebuild the engine to get it all out.

I will keep checking the spark plug for any excess carbon too.

If the piston was in bad shape, something else probably happened to it. Possibly run without any oil. You might still be looking at a new top end.

Nice to see you back, Ericalm! We have missed you! Your insights, experience, and observations help make modern buddy such a valuable resource!

2/3 of two-stoke oil is chemicals to keep oil mixed in gas.
Four stroke oil won't mix properly in gasoline.
Don't know what temperature four stroke oil burns.

Got it all back together. It was not getting any gas to the bowl. After playing with it for hours I bent the float holder a touch and now it is getting gas.
So satisfying to hear the baby purr.

I have now hit another problem. It idles just fine. When I give it gas it just splutters back to idle. It won't move forward more then an inch or two.
Any suggestions?

I have a 70cc kit and Prima exhaust on and also a nice selection of jets. It's so close and I can't wait until I can ride it.

I am going to go premix on the fuel. What ratio would you guys recommend?

The carb still has issues. Clean it completely, including the jets. Does fuel flow freely from the tank?

Fuel does appear to move freely. It wasn't getting any fuel before but moving the float valve position it did allow me to get fuel to it.
I will check it again tomorrow. Will also try putting the original air box on if I can find it.
I will try some different jets tomorrow. It's getting so close to working correctly.