Stihl MS 251 bar question

[rygar]

So i have about a 1 year old MS 251.

I have the 18" bar on it and i was tackling a 3'+ wide log. I had problems getting to the core and cutting it.

Can i put on a larger bar on my saw within hurting the it?

 

[USMC615]

So i have about a 1 year old MS 251.

I have the 18" bar on it and i was tackling a 3'+ wide log. I had problems getting to the core and cutting it.

Can i put on a larger bar on my saw within hurting the it?

I personally wouldn't venture into the 20" bar range with a 251. It should pull a good 18" chain...certainly ain't gonna set no speed records. I think a 16" B&C would be ideal. How's your chain look?

 

[Franny K]

Are you worried about hurting the engine or the part the bar attaches to?

I have a hard nose bar 72 dl 3/8 or 80 to 81 drive links 0.325 modified to fit. I have used picco, 0.325 nk and 0.325 skip on it. Kind of unsafe balance wise.

I also got the longest 3/8 low profile bar Left coast supplies offers and they are real cheap, shortened the tail a bit to make the new oil oil hole work out. That comes out around 67 dl if I recall. With a 6 tooth spur if you compute the gearing and amount of material removed surely if they put an "18" Stihl 0.325 chain on it it should be less load on the engine.

I remove the longer bar when not needed.

 

[Philbert]

There are a couple of factors to consider.

First, is what you can physically mount on the saw. But just
like hooking up a large trailer to a small car, that does not make it a good idea.

The second is the power of the saw to pull the chain and keep it oiled.

Every saw as a "sweet spot" combination of: bar, chain, and sprocket. For the MS250 I think that's a 16 inch bar.

If you have the need to occasionally cut a larger log, you might get away with a longer bar, and skip tooth chain. But if you are cutting them on a regular basis, you really should be looking at a larger (60 - 70 cc) saw.

Maybe rent one and try it out.

Phibert