How the Bar Works

• The guide bar rests on two metal bar posts and an oiler nozzle. It sits several inches in front of the drive sprocket and clutch on the chainsaw. On both edges of the bar, two slots allow the chain to pass over it. At the tip, usually, a nose sprocket allows the chain to pass to the other side of the bar. Since the bar works closely with the clutch, drive sprocket and chain, the right size is crucial for efficient and safe cutting.
  
  

Different Bar Sizes

• Chainsaw guide bars range from 12 to over 40 inches long. Most bars are measured according to their cutting length, which refers to the length from the power head to the furthest cutter on the chain. This length differs from the overall length, which manufacturers use less than the cutting length. A Poulan 14 chainsaw can operate with a bar that's 12, 14, 16 and 18 inches length. However, a larger bar may not always give the best cutting performance.
  
  

Optimal Bar Size

• The optimal bar size for your Poulan chainsaw depends on two main factors. Firstly, the type of wood and thickness of the wood you'll be cutting. If you plan on felling trees and bucking thicker logs, a longer bar will help keep the cut open, allowing it pass through the wood better. However, as the bar gets longer, the chain speed will start slowing down, which may result in a loss of power. Secondly, the size and power of the engine determines the optimum bar size, as the more powerful the engine, the larger the bar it can handle. For general cutting tasks with the 14 Poulan chainsaw, a 14-inch bar will work best.
  
  

Matching Bar and Chain

• Whenever you switch to a new bar size, you also need to switch to a new chain, and possibly, a new drive sprocket. As the bar gets bigger, the chain will also need to get longer so it can fit snugly, but still withstand the stress of cutting. Don't ever try to put a smaller chain onto a larger bar, or try taking links out of a larger chain to fit a smaller bar. This will compromise the integrity of the chain, which can break off and snap back into the sawyer's legs. Also, you'll need to match the gauge, or thickness of the chain's drive links, with the thickness of the guide bar's slots.