Its sort of funny; I also though that a BB engine was heavier than a plain bearing engine, and that the lower RPMs that are normally turned in control line, BB's were simply not necessary and added weight to planes that we want to keep light....
Here, down around post 115, I'm proven wrong by someone that I think frequents this forum and is a veteran C/L builder and flyer.
http://www.rcgroups.com/forums/showthread.php?t=2416091&page=8
So, now I'm confused a bit, but likely to stick to my plain bearing guns. (if possible).
For this site owner, I mean not to detract from this site, I just wanted to point out that there appears to be lots of misinformation floating around.
Well, maybe not so much "misinformation" as simple opinion!
While it's true that typically ball bearing engines weigh a bit more than plain bearing engines, that's not necessarily cast in stone. There are other factors in the weight difference like the size and weight of the crankshaft and case castings.
Actually as brett said above the run characteristics of the engine are more important than the weight (within reason of course). If the engine produces good torque in a relatively flat curve it will likely make a better stunt engine than one that produces gobs of horsepower at high RPM but has a torque curve that peaks and falls. The latter will likely not produce stable consistent speed as it is loaded and unloaded in the stunt pattern. Prop choices can of course greatly effect that situation but it will still be more difficult to control.
The port timing and configuration is in fact more important to make a good consistent stunt engine. Ball bearings can actually be a plus because thier lower drag ratio can make it easier to control the speed differences with load.
The engine in question, in my opinion, has several strikes against it...not just it's weight!
Randy Cuberly
Topic: LA 25 is gone now what? (Read 5755 times)