Wednesday, June 29, 2011

Reid Engine: Two Stroking



Two stroke engines have been around for a long time. Modern two strokes, like your chainsaw engine, have a closed crankcase, which acts as a pumping chamber to pull fuel and air into the engine, then propel the mix to the top of the cylinder. Reid engines used a separate cylinder to charge the power cylinder, and it is fun to watch. This engine is tuned up very well, and it never misses a beat.

2 comments:

Anonymous said...

It seems that this engine maintains a very consistent
speed, more so than some of its 4-cycle brethren, given a power stroke every revolution. Were these engines considered to be better or worse than the 4-strokes? What would have been the advantages/disadvantages?

David aka True Blue Sam said...

Reid's produced more horsepower for their weight than 4-stroke engines of their era, and that was important in machinery that had to be transported to remote locations in difficult terrain. The exhaust port was an important selling point, because you never had to worry about the exhaust valve burning out. Assembling one of these engines on-site was simpler than with 4-stroke engines because there are no timing gears. Here is the location of an article from a 1924 publication, reproduced in Gas Engine Magazine: http://gasengine.farmcollector.com/Gas-Engines/PUMPING-MACHINERY-and-EQUIPMENT-Reid-Engines.aspx