Spur or Rim ???

Fraser · Aug 4, 2003

Hi all,
I am about to change the sprocket on my saw and would like some input about which way to go. The saw I am using is a Poulan 2900 (so it needs all the help it can get) I use it for firewood and cut mostly dry eucaliptus.

Thanks

Fraser

jokers · Aug 4, 2003

Hi Fraser, based on your statement that your saw "needs all the help it can get", I`m assuming that you feel the saw could use more power. Based on that assumption I recommend the spur sprocket. Spurs have slightly less drag than rims and are cheaper. The advantages to the rim system are that you can cheaply and quickly restore prime condition or change gear ratios after making the initial investment. Rims also are easier on the chain. Given that I don`t recall seeing any 6 tooth rims, you can`t gain any mechanical advantage over the standard 7 tooth that the spur is sure to be available in. The rim system is cheaper over the long haul but the rims do seem to show wear faster than spurs.

Russ

Saw Man · Aug 5, 2003

Jokers right on. Would also add the spurs drive up higher on the drive link which is better.

Oregon 33SLP was the orginal chain. It's a chisel chain with 'low profile' cutters.
Switch to Oregon 20LP for a faster cutting chain.
Don't increase the # of sprocket teeth, as you'll slow it down since the torgue curve will drop off, especially in harder wood.
Let the 20LP make the difference.

Fraser · Aug 6, 2003

Thanks for the info. I have worn out the original chain a while ago and have been using Stihl RS chain which seems to cut better and it stays sharp for a long time.

Fraser

Saw Man · Aug 6, 2003

Stihl RS cutters are 'opened up' and Pro styled than the Oregon 33 series which isn't a true Pro style shape & size cutter.

Prefer the 20LP over the RS due to the'Vibe Ban' chassis, and Lube links.

However both Oregon's 20LP & the RS are better choices, and will give you better results.