More aggressive chain on a low profile bar/sprocket?

[Softdraw]

I have yet to find a definitive answer to this question: Will a saw that normally runs a low profile chain (say a 3/8 pitch, .050 gauge), accept and safely run a more aggressive 3/8 pitch, 0.050 chisel or semi chisel chain without modifying the saw's sprocket or bar?

 

[hotshot]

I have yet to find a definitive answer to this question: Will a saw that normally runs a low profile chain (say a 3/8 pitch, .050 gauge), accept and safely run a more aggressive 3/8 pitch, 0.050 chisel or semi chisel chain without modifying the saw's sprocket or bar?

No definitive answer is available, as it always depends on the saws components.

Most of the time it works with 7 tooth spur drive drum sprockets, but 3/8” rim drives don’t mix as the pico (lopro) drive link bases are shorter lengthwise. The little 6 tooth spur sprockets won’t run a full house chain as the diameter is too small for the larger chains’ bend radius.

Some sprocket tips on lopro bars will make the chain ride too high off the bar nose with full house chain.

You also need a minimum 45cc size saw with balls (torque) to make the jump, otherwise it just stalls the saw too easy.

I once ran a loop of full-size 72LGX chain on a torquey 38cc S25CV Poulan. Wanted to use it for a quick limbing saw. However, the initial “bite” into wood is too big, versus the light mass of the small saw, and it jerked the saw away from your hand, which was not safe.

Sounds like you need to buy a bigger saw, but you didn’t provide enough information to tell.

 

[Softdraw]

No definitive answer is available, as it always depends on the saws components.

Most of the time it works with 7 tooth spur drive drum sprockets, but 3/8” rim drives don’t mix as the pico (lopro) drive link bases are shorter lengthwise. The little 6 tooth spur sprockets won’t run a full house chain as the diameter is too small for the larger chains’ bend radius.

Some sprocket tips on lopro bars will make the chain ride too high off the bar nose with full house chain.

You also need a minimum 45cc size saw with balls (torque) to make the jump, otherwise it just stalls the saw too easy.

I once ran a loop of full-size 72LGX chain on a torquey 38cc S25CV Poulan. Wanted to use it for a quick limbing saw. However, the initial “bite” into wood is too big, versus the light mass of the small saw, and it jerked the saw away from your hand, which was not safe.

Sounds like you need to buy a bigger saw, but you didn’t provide enough information to tell.

Thank you. I am trying to squeeze a bit more out of a Poulan Pro PP5020AV. It's a 50 cc saw. I thought I'd use a shorter bar and more aggressive chain. The 20" bar it runs is okay but I can't help but think a shorter bar/stronger chain would help.

 

[hotshot]

That’s a good thought, and a good weight saw.

Take your time & pick up a 14” bar & sprocket to try, as your saw drive sprocket is already made for the bigger 72 series Oregon chain, I believe that saw uses a K095 mount.

 

[Softdraw]

That’s a good thought, and a good weight saw.

Take your time & pick up a 14” bar & sprocket to try, as your saw drive sprocket is already made for the bigger 72 series Oregon chain, I believe that saw uses a K095 mount.

That's what I am trying to avoid. I'd like a shorter bar and more aggressive chain on the same (original) sprocket. Will the current sprocket not work?

 

[hotshot]

That's what I am trying to avoid. I'd like a shorter bar and more aggressive chain on the same (original) sprocket. Will the current sprocket not work?

Yes, the current drive sprocket will work!

I always start with a fresh sprocket with a new chain...but you don’t have to.

 

[Softdraw]

Yes, the current drive sprocket will work!

I always start with a fresh sprocket with a new chain...but you don’t have to.

Excellent. Thank you. I like this saw. I know some of them get bad raps but mine has been terrific. A little extra "oomph" with a shorter bar and stronger chain and I will be set.

 

[Ryan'smilling]

Excellent. Thank you. I like this saw. I know some of them get bad raps but mine has been terrific. A little extra "oomph" with a shorter bar and stronger chain and I will be set.

I'm not sure what you mean by oomph. That saw is unlikely to cut any faster with full sized 3/8 chain. Probably a fair amount slower. If you want a faster cut, try Stihl PS chain. Open up the muffler maybe. A shorter bar though, I can get behind that idea.

 

[old guy]

The 5020 does not come with lo-pro, it already has full 3/8 chain, and yes a 16'' bar works well.
I have 3 5020's.

 

[Little Al]

I'm not sure what you mean by oomph. That saw is unlikely to cut any faster with full sized 3/8 chain. Probably a fair amount slower. If you want a faster cut, try Stihl PS chain. Open up the muffler maybe. A shorter bar though, I can get behind that idea.

As said in post#8 a Stihl PS lo pro chain sharpened to razor sharp will out cut a std 3/8 1.3 chain on a saw that size power Narrow Kerf cut & all that