Breaking in a Stihl 500i, any tips?

Speaking saws in general. Obviously we can’t tune an injected or mtronic saw. On those I still let them warm up plenty. A few minutes at idle doesn’t hurt anything

 

Just asking your opinion here. Motorcycles (not sure about cars/trucks) come or used to come with break-in oil in the crankcase. This would allow the rings to properly seat before using the “good stuff”. Typically it was advised to run it for about 600 miles. Wouldn’t using a very rich mix of oil in the gas slow down the seating of those rings or ring? And are autotune saws perfectly fine with 16 or 32/1 ratios?
Not referring to tuning rich, but the amount of oil.

 

I've got some things to do this morning but it looks like I will have some time this afternoon to finally run this thing. I'll be using some leftover Moto Mix I had to buy when I borrowed a polesaw this past summer. Pics to follow.

 

Yes this is true.

I am an engine builder by trade and have run multiple tests on this subject.
Break in oil is a conventional oil that often contains a lot of zinc. This allows the rings to actually grind themselves into the cylinder bores for proper ring seal.
Synthetic oil can actually glaze the cylinder walls not allowing the rings to seat themselves.
We found this out with numerous dyno tests.

So now the question?
How does this same thing come into play with todays 2 cycle oils that are often full synthetic.
Being from the automotive end of things I don't have an honest answer.

I never broke any of my saws in with a break in 2 stroke oil and then switched.
I run 40-1 in everything anyway so extra oil was never an issue during break in.

Anyone have any thoughts?

 

Due to this fact many circle track engine builders use Marvel Mystery Oil as assembly lube for the piston rings and cylinder bores. Usually by the time you are done turning the crank to install all the pistons, the rings have started to seat. I’ve also used it successfully in the gas on a new SHO 250 outboard that was “making oil” to get the rings to seat.

 

Is the Stihl 2 cycle oil that they use in moto mix synthetic? I imagine it is, but I'm pretty clueless on that.

 

I believe so.
Silver bottle oil is what I was told.

 

I typically just go easy for 2 or 3 tanks and always let them warm up good, when they're new and after, but moreso when new. After that, it's game on.

Congratulations on the new saw! I love my 500, after I stiffened things up a bit.

 

I'm sure with Stihl premixed you'd be fine. When you start almost doubling the oil content, that's what made me curious enough to ask someone that's been there/done that many more times than I.

 

x2

 

I like the added oil at least for the first few tanks to help with scuffing from anything that’s not perfect inside.

Some cylinders zero out perfectly on the lathe, and some jump up and down +-.001” every 90° of rotation at the bottom of the plating. It causes premature scuffing and wear marks that may or may not lead to something bigger down the road.

More oil will lengthen break-in time, but I haven’t seen adverse effects as long as the saw gets worked hard.

How/if the AT/mtron stuff runs depends on the specific oil as much as the ratio. Motul 800, BelRay H1R, Red Armor…thicker stuff…supposedly doesn’t act right in some AT saws at heavier ratios. The jets can’t or are reluctant to open enough to flow the more viscous mix. So far with my gas, my elevation, ambient temps and humidity, amsoil dominator, saber, and Schaeffers all do fine in every saw so far at 32:1. For the thicker oils mentioned above, I recommend 40:1 to customers that inquire about them

 

I dunno, we should have another best mix oil and ratio discussion to clear everything up once and for all

 

Sorry.

 

It’s very confusing. And it only spreads rumor when folks take off their muffler and see a wet piston, so they’re satisfied. I like to see a small puddle of oil in the bottom of the crankcase after it sits for a couple days. I’m sure it’s an extremely low percentage of guys who are ever going to go that far.

 

Years ago when any logger bought a new saw from out only place to buy news saws, the owner would fire them up and let them idle on a fence post out back for about 20 minutes while you had a couple beers with him. That was about it.

I broke in my 500 the same way, and then just went to work like any other saw. I did learn that letting it idle first thing in the morning for a minute or two seemed to help gets it's mind right so to speak.

 

If I was snowed in, couldn’t make it to work, wife and kid aren’t home, nothing on Netflix, I might go that far on a 2 series Husky.

 

I only use full mineral for 2 stroke break-in plus a break-in process that most people won't spend the time to do even if they knew it existed. Was taught to do so by the engine builders for the German FG Modelsport 1/5 scale RC race team. Its a big deal in the RC world, Car and boat for sure and probably flying RC as well. All at 25:1 as that's the recommended ratio for these air cooled, high revving, non EPA regulated engines. I follow their break in process to this day and go through a series of heat cycles before driving the RC car or cutting with the saw. It's very similar to the La Sleeve break-in for bikes except you aren't riding it and no plug chop at the end. They are tuned a bit fat if a manual adjust carb. I actually ran a full mineral oil called Blue marble full time up until 3 years ago or so. Ran it in everything.

 

In my ms201 Manual it says no zero load full throttle for 3 full tanks. The end. Probably says that in the 241 manual too.

 

I pick up another 500i Wednesday, so I will bird dog this thread for a few days. Got a big ash to drop!!! But using an older saw this time!!!

 

Really? Pizz rev it for 3 tanks?
That doesn't sound right...