Break-in

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I’m no expert, that’s for sure. But all 2 stroke power equipment I’ve ever had since new I just let warm up for a minute or 2 on the first startup and ran a full tank of fuel at varied throttle and loads. After that bobs your uncle run it like you want to. Always had good luck for the most part
 
I'm sure your right, but when I bought a brand new saw I had other components in mind when thermal cycling.
Rod bearing, wrist pin bearing, crank bearings & seals ect...

It's been awhile since I bought a new saw, & like I said I never had any problems doing it (no glazed cylinders).

I prolly wont do it again, but it's a good way for problems to show themselves @ idle rpm's instead of WOT.
None of what you mentioned needs a break in period.
I believed in break in for years. That was until I watched a really good engine builder break in a motor I had him build for my mod hill climb sled. He did it on a dyno at full load once the coolant was up to operating temp. It gained power with each pull until it hit a plateau. At that point it was broken in. By that point the pipes were so hot the paint had burnt off the header sections! That particular motor was monster and it lasted a very long time under heavy abuse.
No one believes till they see it happen on a dyno. Did the same thing for years, just with big diesels. Blow by meter was what I would watch for rings seating. After a few pulls the blow by would drop drastically and she would make some mean power.
Glazing actually is a term used to describe the rings folding over the cross hatch on cylinder with out "seating" the ring. It can't really be observed visually. Instead it manifests itself as the engine making less power over its lifetime because the rings never seal as intended.
Never seen it in person, but the owner of the machine shop I worked at had talked about it several times when I was first learning to run the dyno. Not a fun day from what I've been told.
 
A chainsaw is heated up in 30 seconds, warming is just wasting gas and not helping squat. And the Dino thing about being better to break in engines is just pure internet hogwash too. Crank them and run them, like they were designed to do.
 
A chainsaw is heated up in 30 seconds, warming is just wasting gas and not helping squat. And the Dino thing about being better to break in engines is just pure internet hogwash too. Crank them and run them, like they were designed to do.
Exactly.
When I am breaking a new saw in I purposely try to load it as hard as possible.
 
A chainsaw is heated up in 30 seconds, warming is just wasting gas and not helping squat. And the Dino thing about being better to break in engines is just pure internet hogwash too. Crank them and run them, like they were designed to do.
The dyno I will disagree with, the rest as Bwalker says load it as best as you can. Well a dyno will load it 100% as long as you want. And you can watch everything 100% down to air fuel ratio. We made 2 partial pulls and 1 full pull on my new engine and by the end of the 3rd pull the blowby was gone and it gained over 30hp at 6500 rpm. Last pull was only a 5hp gain so it is close to being done. DO NOT IDLE A FRESH ENGINE TOO LONG. As was said, worst thing you can do. Look at the SHO Yamaha and their piss poor break in procedure and you will see what a easy break in does. Pages and pages of engines making oil and using oil. Cj
 

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