Question on using a 20" bar

[fredx]

I have a Stihl MS 251 that is VERY slightly modified ( timing advance and gutted the muffler somewhat ) and has noticeably more power now. It has an 18" bar on it and I would like to move up to a 20". My local sthil dealer said no, it wont fit. I was hoping to go with one of those light rollomatic light bars. Has anyone fitted a 20" on a 251? If so will it just fit or is there some modifications that need to be made. I wonder if it has to do with the oiling not lining up to feed oil to it.

 

[Duane(Pa)]

I'm not familiar. Does it have a single bar nut?

 

[sawmikaze]

You can get an aftermarket bar ( cannon ) for it in Picco. Stihl doesn't make a 3005 mount bar in a 20".

It's not gonna oil it well, I wouldn't plan on making any full bar cuts in dry wood with it.

 

[fredx]

I'm not familiar. Does it have a single bar nut?

No- it has two

 

[fredx]

You can get an aftermarket bar ( cannon ) for it in Picco. Stihl doesn't make a 3005 mount bar in a 20".

It's not gonna oil it well, I wouldn't plan on making any full bar cuts in dry wood with it.

OK- thanks for the input fellas- i will just keep the 18 on it

 

[Duane(Pa)]

OK- thanks for the input fellas- i will just keep the 18 on it

What chain size? You may be able to improve performance with a different type of chain on the bar you have.

 

[fredx]

Not that I have any strong points - but my weakest understanding when it comes to saws has to do with chains, so I pretty much have no clue, or know just enough to be dangerous / mixture of correct understanding and wrong understandings.
I think most of my chains are of the "yellow box" but i do have some green box chains also. I am thinking the yellow are better / more agressive?
I have always wanted one of those chains that throw the big chips instead of the finer ones

 

[hacskaroly]

I am thinking the yellow are better / more agressive?

The only difference between the green and yellow (aside from various cutter profiles) is that the green chain drivers have a small hump on them which are supposed to help reduce the chance of kickback. Some people call this a "safety chain", "beginner chain" or "less aggressive". Both chains will cut your leg off if you give it a chance and you probably won't notice a difference in pain between the two.

As for chips, if you have a sharp chain (also proper depth gauge), it should be producing chips and larger chain (3/8-.404 vs. 3/8p-.325) will produce larger chips.

If your 251 is running a .325 chain, there are a few companies who do sell skip chain in that size. You might see a slight performance improvement/difference in that chain type vs. full comp versions (yellow or green).

 

[tree monkey]

time for a ms261

 

[sawmikaze]

OK- thanks for the input fellas- i will just keep the 18 on it

I'm assuming that your saw has .325 on it because that's what they come from the factory with.

You can convert it over to picco with a drum or a rim set up if you wanna make it a little more zippy at the expense of durability...that's up to you.

And if you do have .325 on it and you aren't already running narrow kerf .325 with RSP chain...do that.

 

[Stump Shot]

time for a ported ms261

Fixeded.

 

[Sloughfoot]

026 is what he "needs" because I have leftover stuff and things.

 

[fredx]

Thanks for all the suggestions fellas- really appreciate you folks chiming in. I have way to many saws to begin with and really only use a few of them. but I have two saws in the 40 cc range with 18" bars- just wanted to put a 20" on one of them.

 

[hacskaroly]

have two saws in the 40 cc range with 18" bars- just wanted to put a 20" on one of them.

You would be better to look at a 50cc-ish saw for a 20" which would also handle 3/8 chain which gives you more cutter-type options.

I did see a video where a guy took a Poulan Wild Thing, ported it and then put a 32" bar on it, it pulled it, though not sure how well it oiled

 

[Sloughfoot]

You would be better to look at a 50cc-ish saw for a 20" which would also handle 3/8 chain which gives you more cutter-type options.

I did see a video where a guy took a Poulan Wild Thing, ported it and then put a 32" bar on it, it pulled it, though not sure how well it oiled

It's unfortunate that 2 40cc saws doesn't equal 80cc.

 

[Cat 525]

Just get a Husky and throw a 20 on it and let it rip. Seems like the Stihl guys have had to use things 2" shorter all their lives!,, Happy Thanksgiving!

 

[fredx]

You would be better to look at a 50cc-ish saw for a 20" which would also handle 3/8 chain which gives you more cutter-type options.

I did see a video where a guy took a Poulan Wild Thing, ported it and then put a 32" bar on it, it pulled it, though not sure how well it oiled

I have a ported Echo 590 with a 24" on it that pulls pretty good
I just might end up going back with a 20" on that one since it's not looking like a 20 is going on the 251