very small high horsepower airplane engine

[ratdoggg]

I am talking about a 50cc with 4.5 horse power!!

 

[DuctTapedGoat]

Is it going to be a cost effective motor, or is it a money is no option thing you're gonna do it to do it no matter what it takes to get it done thing?

You're going to have to fab stuff up. As well, what do you expect your RPM to be off that motor? If you're talking about doing a friction drive, don't expect to take full advantage of the HP.

 

[schulze 123]

Hi Guys,
This is just my 2 cents worth but hope it helps. I work in the Aeromodelling industry and have used various parts (carbies and exhausts) with good success. So for this topic I will use the DLE 55cc 2 stroke as the example.

Pros - 55cc (similar to most MB engines)
- 5.5hp at 7500rpm (excellent)
- 1.5kg all up weight (excellent)
- Torque figures not available but they swing a large coarse pitch prop
- Great fuel economy (well in an aircraft )
- Walbro carby (great mixture control)
- Reeded induction (good for bottom end grunt)

Cons - Virtually no suitable mounting points on the crankcase.
- Crankshaft is only supported on one side, HT motor has both sides.
- Attaching clutch/sprocket to the crank shaft very difficult as the
shaft is very small in diameter and is approx 100mm from the only
mount on the crankcase (bad for our application).
- Ignition system albeit far more advanced than the HT, requires a
separate power supply (4.8volts) to operate it.
- The cooling fin area is less than 1/4 of the HT and would more than
likely overheat (no forced air cooling from prop)
- Supplied exhaust would be too loud (yes that can be changed)
- Price $540.00AU (not good for the hip pocket)

Conclusion - After spending a large amount of money buying the motor and then another bucket full adapting it to your bike, you will have a machine that will go like stink on the smell of an oily rag. Then when you're all smiles the thing rips itself out of the frame just as the crankshaft turns into a pretzel, the barrel distorts due to excessive heat and the spark gives out because you forgot to charge the ignition battery .
If this were an easy cost effective project I would have definitely pursued it as there are many of these motors available at my work.

Again just my 2 cents worth as I hate to quell peoples enthusiasm.

Cheers BJ

 

[HeadSmess]

i still like the idea, but there is a major issue. friction drive. wont work. neither will direct drive.

generating electricity on the go though...thats possible.

envision, if you may, the OS rotary. a very expensive engine yes (about what i paid for my cnc mill giving me the capability of making my own )

but anyways. at 5cc, this lil beastie can produce 1.2hp from memory.

yes, yes, its tiny, runs on nitro, blah blah. and its a rotary!

ha ha! running a generator, you run it at one rpm basically. just what rotors actually like.

can we go back to the daydream please? ok.

so you couple this here rotary to a large brushless motor. these work quite nicely as generators. there you are....

yes, i have a mill. im basically thinking a 10-20 cc petrol rotary, combined with a smalll genny, ducted with a fan. a nice, compact cylinder... say the size of a drink bottle.

i can make something like this with some time.

then a decent E-hub, speed controller...

but as one off's or low vol production...the price would be prohibitive. soz


and quoting ratdogg

I am talking about a 50cc with 4.5 horse power!!

kx60....60 cc making probably 10 hp.....or more. been on one?

 

[loquin]

I am talking about a 50cc with 4.5 horse power!!

Along the same lines (but a lot more practical) is the GP460... : 46cc, 4.2HP+ at 11000 RPM.

$255 at DDM

And, it has the cooling fan built-in, self-powered ignition system already there, standard clutch already there.

Now, that being said, this is a very powerful motor for a friction drive application; another member has stated that they have this combination, and they're tired of the excess power spinning the drive spindle. (and, as a result, they're moving to BMP's chain drive jackshaft add-on)

 

[5-7HEAVEN]

I ran a GP460 engine on a BMP friction drive. It ran great on one of my bikes, but loved to eat tires. On another bike, its appetite was so voracious that it ate a new tire in two weeks. Whenever I started the engine, the engine would scream and literally dig out a chunk of rubber. In a week or so, there was a divot every inch or so around the entire tread surface!

Now I run a 460 with chain drive/shift kit. My rear tire look great, but now the engine has an appetite for 8-speed chains.

 

[5-7HEAVEN]

Along the same lines (but a lot more practical) is the GP460... : 46cc, 4.2HP+ at 11000 RPM.

$255 at DDM

And, it has the cooling fan built-in, self-powered ignition system already there, standard clutch already there.

Now, that being said, this is a very powerful motor for a friction drive application; another member has stated that they have this combination, and they're tired of the excess power spinning the drive spindle. (and, as a result, they're moving to BMP's chain drive jackshaft add-on)

The GP460 has a very narrow power band. It does NOT like to climb steep hills with a single gear ratio. The 460 works VERY well with a shift kit or NuVinci hub.

 

[Tanaka40]

How about this former rammer engine

I have a solution for this problem. This link is for a subaru-robin that is now listed on ebay. I do not know if it will work but the engine is rated at 3.3 peak HP. http://cgi.ebay.com/3-3hp-Robin-Eng...&otn=4&po=LVI&ps=63&clkid=6540752886719350990

 

[5-7HEAVEN]

How heavy is it, and what size clutch does it have?

 

[tjs323626]

(I have a solution for this problem. This link is for a subaru-robin that is now listed on ebay. I do not know if it will work but the engine is rated at 3.3 peak HP. http://cgi.ebay.com/3-3hp-Robin-Engi...52886719350990)

That engine looks good. I would like to know which clutch fits it. I have 2 small Sachs engines I plan to use on bikes. The mounting and clutch will be a challange. The quality of the German engines is great.