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AX Motors in general


Old 04-07-2012, 07:48 AM
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Default AX Motors in general


I cut and pasted below a quote from one of your posts in the thread on the 55ax cutting out.

"It should be broken-in at full throttle with the high-speed needle set just lean of the "two-cycle/four-cycle break". Then, it should be gradually leaned towards peak RPM over the next 30-45 minutes."

I have two questions in general on the AX motors (I have the 65 and the 55):

1. The manual suggests a break-in procedure that is no different from anything I remember...ever...with nitro engines. Run at full throttle, 10 seconds rich, 10 seconds lean(er), 10 seconds rich, 10 seconds lean (er) etc until the tank is empty...repeat. Your quote above suggests to me something that is different than what is specified in the manual. Are you saying something a little different? I'll take what you clarify as authoritative as frankly the varying opinions on RCU drive me nuts...keep them cool, get them hot, ringed, abc...tapered sleeve etc. etc. there doesn't seem to be any consensus around what is in the manual! Crazy...anyway, what say ye?

2. Over the years I have had several OS engines and they are pretty much the only 2 strokes I care to get involved with. I have always hand started them with a couple flips and hardly ever touched the needles once they were set...left them alone literally for years! I have noticed on the 65AX though, that I have to use an electric starter. It may start by hand if it is hot...but a cold engine won't even pop by hand. The manual says it is designed to be started with an electric starter. Is this a safety thing...or is there actually a design feature that promotes electric starting (maybe an AX model design feature?)?

Please let me know your thoughts and thank you!

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Old 04-09-2012, 05:57 AM
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Default RE: AX Motors in general

You can use the manual, or use our FAQ. Either will give you a properly-broken-in engine with no damage. With a non-ringed engine, it is very desirable to have a significant part of the oil content to be castor oil

Some engines need an electric starter because of their timing. With most glow engines, though, you should be able to hand-flip it once it's properly-primed. Cold engines, though, may be a different situation. The manual states that the engine was "designed" for an electric starter. That means you can use a starter without harming the engine, and they also recommend it because it does keep fingers away from the propeller.
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