Motorized bike build

Yea, the grave might show up sooner than you want. You can try 25 or 32:1 next engine.
I agree, never go under 32:1 on one of these cheapie engines! If you want to protect your investment, at least 32:1 on stock china dolls (and mine carried me at almost 300#), but 25:1 on high performance build or high revving builds.

IDK why anyone would buy premix, it's too costly, but if you MUST for your first gallon, at least get some 2 stroke oil too and add the required ounce or few to make a good 16:1 for break in and then go to 32:1 after your first tank. You probably can get away with saving a buck or two getting just one can and some oil to beef it up for your use, in that you may be able to not buy the gas can and just reuse the can the premix cam in (if it's a nice metal one). I mean eventually you'll want a good gas can, but to start on that might get you by a few weeks as these really do not burn fuel fast...

You *might* consider California Motorbikes, just because they have PayPal financing, and good prices, but there is no actual warranty. They are at least better quality than most Ebay or Amazon motors AFAIK. Mine came with the piston installed and I was able to flake out the casting slag without removing it. You'll want small needle nose pliers for the piston wrist pin circlips if you go that way. I managed mine without ever pulling the piston out of the bore, but I recently did the gaskets and getting the piston in isn't hard, you can hold the rings with your fingers and oil the bore with 2 stroke oil, and it goes in pretty easily.

If there's something actually defective, you can probably get help from the owner here through the forum, but I gather he's not the greatest to deal with via normal channels. Probably gets too many emails and pays too little attention...

I wish you the best of luck on the project. Please don't take people's coarseness (on occasion) here too seriously. Just about all of us really just wish to be of help.
 
40:1 cradle to grave is for guys who can chuck another on every 6 weeks.
For the vast majority of members here 32:1+ is solid advice.
I think sometimes advanced engine builders suggest 40:1 but fail to take in to account the builders stage of understanding how to build and run a motorized bicycle engine.

Any added stress and excess heat from an improperly set up and tuned build will not survive low oil ratios.

It’s too cheap of an insurance to not add a bit of extra oil.

Unfortunately for many learning no amount of oil will save an early demise. It takes time and patience to learn how to build one of these bikes and correctly tune it.
 

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