Nice engine,Scootmeister. Compression is great, said to be 10:1.....and it fit with the test!! Found some minor changes on it from original...The pipeframe was orginally a propanetank with a burner in front on a non electrical plug, open the propane valve, fire up, and wait for the metalplug (top of pic 2)to get red hot, and use the rope! This burner is removed and pipe plugged, perhaps because a lot of trouble with leakage on the propane, and used a stand alone torch instead. Well, its also have a springed rope-puller, who are very rare,no info says that the Norwegian saw could have been built with this.Even if the later Swedish saw had it as extra accessories, but it dont look like this one........and this one is also branded Comet....Removed,the normal rope pulley was under it.