Originally Posted by
Rudeboy
The engine business is just a hobby for guys like Dub Jett. They make them because they have the machinery to do so. If the market dries up any further, I wouldn't be surprised if even he throws in the towel. I certainly don't expect any major development...there's just no way to break even on a few hundred engines.
If guys like Jett come out with something new, it is basically out of love for the hobby.
I broke in an ASP .36 yesterday, 8x6-8x7 props, mousse can muffler, FAI 80/20 fuel: 18K+ rpm. It runs and throttles fine, but it is just not as sweet as a Webra. You can tell the engine is maxed out in it's stock trim. Behaves fine up to about 14K, then it starts to vibrate. It is not balanced for higher speeds. A good sport engine, if you run it on a 10x6 or 10x7, but other than that it is just a run of the mill chinese cheap engine. So basically, I'm disappointed even before the engine gets flown.
I'd gladly pay two times as much for an engine that is 10% better...
I think the ASP series of engines are powerful by design but the manufacturing isn't up to the design criteria in some cases. I would tear your's completely down to just an empty case and check everything with a fine toothed comb. I did this with a ASP .12. The bearings fit the case too loosely and fit the crankshaft too tight. By the time I corrected the problems it took 2 reassemblies until I got the bearings back into the case just right to achieve the free spinning crankshaft that comes to a gradual stop after you twirl it.
The piston had excess material that I removed free hand. The engine ran smooth, but correcting an out of balance engine can be as simple as removing material from the piston. If the condition worsens, no big deal...just remove material from the counterweight until it runs smoothly.
I raised the exhaust timing to 170 degrees [without a liner shim] and made a liner shim that gave 180 degrees of exhaust. I spent a couple nights with this $30 engine, but it is part of my hobby, anyway.