Two stroke engine break-in

[Pablo]

Is there anything special, other than avoiding sustained FULL rpm's during break-in, for 2 strokers?

I made my fuel oil mix a bit oil rich for the break-in period. Is this whacked?

 

[blano]

I would run the same mix ratio as you plan on runningafter break in. The idea of adding more oil comes form the fact that many engines with oil injection call for the practice as insurance against a failty oil pump. As far as break in goes. I always heat cycle the engine 3-5 times before I actually use. I then warm up the engine completly and subject the engine to a heavy load followed by a cool down period. With out a load the rings will not seat.

 

[darrenc]

Pablo,

This is not whacked. Most two-stroke outboard manufactures have you run a rich mixture for break-in before using the recommended ratio. I think it’s good practice while you are seating the rings, etc. 25:1 is what I use for the first hour or so of operation of a lawn and garden-type 2-stroke. After that, I use anything from 50:1 to 100:1 with your favorite brand of synthetic oil.

 

[Schmoe]

Only problem is not "flooring" it while your trying to break it in. I mean like you have a new 4 wheeler or dirt bike, you know you want to gas it because you want check out the power. Hard not to do that.

 

[Smoky14]

I also think a richer oil mix is good. Just remember that a rich oil mix will mean a lean fuel mixture so take it easy until you get it jetted on the mixture you intend to run.
I've rebuilt a lot of 2strokes where people went overboard with the oil and forgot that it leans the fuel mix.
Good riding and keep the shiney side UP

 

[harbor]

blano - What is your process for heat cycling a 2 stroker?

Thanks,

Harbor

 

[Cujet]

One thing I always keep in mind is that the small commercial 2 strokes have very low power output for the displacement. Therefore I feel they are not highly tuned or highly stressed 2 strokes. By cc comparison, a well tuned 32cc 2 stroke motocross bike would make over 10HP! I think those engines are designed to go full bore nearly right away.

Chris

 

[blano]

Harbor, A heat cycle is basicaly warming the motor up tomoperating temp and then letting it cool down completely. This is done to relieve any pent up stress in the metal companents of the motor.