Cheap Chinese 2 stroke engines.
#1

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I have just seen this 49 cc 2 stroke advertised on Aliexpress:
http://www.aliexpress.com/item/Hm-va...74_75,201409_1
Has anyone converted one of these for aircraft power? Or can anyone comment about the quality etc.?
Thanks,
Jim.
http://www.aliexpress.com/item/Hm-va...74_75,201409_1
Has anyone converted one of these for aircraft power? Or can anyone comment about the quality etc.?
Thanks,
Jim.
#2

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From the looks of it there would be a lot of required removal of such things as the recoil starter and front pully. It looks like a heavy crankcase and no telling what else to convert to aircraft use and then it still may not be really
practicle to do so? NOT FOR ME, burned often enought by my ideas that don't work out well, but then?
practicle to do so? NOT FOR ME, burned often enought by my ideas that don't work out well, but then?

#3

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Yes, come to think of it, not a really good idea. I have had bad experiences with Chinese bearings. The poor quality of them is legendary apparently.
But thanks for the reply Gizmo.
But thanks for the reply Gizmo.
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The Chinese make some really good Gas two strokes such as DLE, etc. They also turn out some really cheap junk and yes I know about their bearings altho the better engines seem to have good bearings, at least thats been my experiance, I usually avoid their bearings when buying new ones at the bearing supply I use, just me.
#5


It looks like a small motorbike/Goped motor.
I've looked at one once and decided it's probably too heavy for air applications.
The best conversions come out of chainsaws and to a lesser extent weedies/blowers.
I have a 37cc from a chainsaw and a 52cc from a large brushcuter, both new and in the process of being cut/converted.
The 37cc looks like a powerful engine with huge transfer ports (2 x 2) and a generous inlet and exhaust ports.
I think it will be significantly more powerful than the Homelite 33cc chainsaw engine I converted which is very nice. Just need the time...
I've looked at one once and decided it's probably too heavy for air applications.
The best conversions come out of chainsaws and to a lesser extent weedies/blowers.
I have a 37cc from a chainsaw and a 52cc from a large brushcuter, both new and in the process of being cut/converted.
The 37cc looks like a powerful engine with huge transfer ports (2 x 2) and a generous inlet and exhaust ports.
I think it will be significantly more powerful than the Homelite 33cc chainsaw engine I converted which is very nice. Just need the time...
#6

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Yes, it does look to be heavy. I've more or less come to the same conclusion as you. Pity, as I can get one into this country with free shipping. Would only cost around A$40 or so!
#7

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I agree with everything that's been said about the engine, and also about chainsaw engines. The only caveat is, if you are considering a particular chainsaw candidate, look up a parts diagram for it FIRST. Many saws are made with the engine as part of a huge case that includes the oil tank, sometimes the fuel tank too, etc. These are difficult to convert and design a mounting for. I have a Stihl 62cc that was like that. It's a great engine, but MAN was it a bunch of work to convert!
AV8TOR
AV8TOR
Last edited by av8tor1977; 10-08-2015 at 06:59 AM.
#8

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I see exactly what you mean Av8tor! I have a 66 cc Stihl partly stripped and this one has the crankcase integrated with the oil tank etc.
It will be a lot of work, true, but so far I don't see it as formidable. It came for free, so I consider it worth a bit of effort.
Is it dangerous grinding off the magnesium alloy castings with a grinder? I recall you mentioning something previously about "being careful" about such, what did you meant by that please?
I have started a new thread on this project here:
http://www.rcuniverse.com/forum/engi...onversion.html
It will be a lot of work, true, but so far I don't see it as formidable. It came for free, so I consider it worth a bit of effort.
Is it dangerous grinding off the magnesium alloy castings with a grinder? I recall you mentioning something previously about "being careful" about such, what did you meant by that please?
I have started a new thread on this project here:
http://www.rcuniverse.com/forum/engi...onversion.html
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