very small high horsepower airplane engine

[ratdoggg]

I have been looking at some of these small engines they use on
r/c airplanes.. Some of these have very high horse power for a very small engine.
Question is this: These engines are made to use a prop and do not have a flywheel.
Would they work with a friction drive bicycle. One day I think it would (using the bike
wheel as the flywheel) then the next I think it would not any body have any experience
with something like this???

 

[DuctTapedGoat]

Well, I'll say this.

I'm looking at 2stroke <1cc vintage plane motors to do a motorized flip trick bike (finger bike).

 

[Wheres my dog]

Ratdoggg... indeed very high horsepower BUT what is needed to turn that bicycle wheel is horsepower along with torque!

If you think about the propeller spinning there is very very little resistance against it turning hence the low torque range.

From all I have read and seen, they are not a worthy candidate for a friction drive

 

[Skyliner70cc]

Depends on the size engine you plan to use. Torque is what spins a prop and there is mucho resistance that a prop experience. The resistance is proportional to the size of the prop the engine can pull.

This RC engine would be a sweet ride but factors such as cooling may be an issue since larger cooling fans would be needed for a bike application.

http://www.desertaircraft.com/engines_detail.php?Page=DA-200

Specifications
Displacement: 12.20 ci (200 cc)
Output: 19 hp
Weight: 10.95 lbs (4.95 kilos)
Bore: 1.6771 in (42.6 mm)
Stroke: 1.3779 in (35 mm)
Length: 9.625 in (244 mm)
RPM Range: 900 - 6,700
RPM Max: 8,500
Fuel Consumption: 4.5 oz/min @ 6,000 RPM
Warranty: Two years

Features
Four petal reed valve, bottom induction.
Desert Aircraft, auto advance, electronic ignition.
Walbro Carburator
Exclusive Desert Aircraft designed cylinders, pistons, and crankshaft.
CNC milled, 7075 aluminum alloy crankcase.
Low vibration.
Long rod to stroke ratio.
Aerobatic power curve.

 

[Skyliner70cc]

This small 400cc radial radio control model airplane engine is pretty sweet but I'm sure it desn't have enough torque to pull a string out of a puppies but ;-)

http://www.troybuiltmodels.com/items/RCS400R.html

It could easily fly a model airplane in excess of 100 lbs.

Now, if the OP was talking about smaller engines, i agree a .40 cubic engine (1.2 hp) ENGINE ISN'T GOING TO CUT IT FOR A BIKE. That engine produces that 1.2hp at 17000 rpm and you will need a reduction to convert that to a useable operation (not practical).

 

[Skyliner70cc]

This engine would be a favorite of mine.
JetCat SPT5H Engine complete with starter.
Specifications:
Power: 11.2Hp
Weight: 4.9 LB, incl. starter
Length: 15.25 inches
Turbine RPM Range: 50,000 - 165,000
Gearbox RPM Range: 1500 - 7000 RPM
Exhaust gas temp.: 580°C -710°C
Fuel consumption: 8 oz per/min at full power
Fuel: Jet A1, 1-K kerosene
Lubrication: approximately 5% synthetic turbine oil in the fuel
Maintenance interval: 25 hours

http://www.variocanada.com/product_info.php?cPath=112&products_id=3165

 

[ratdoggg]

The reason that I got interested is that I found out that weed wacker conversions are popular
conversions for large r/c air craft and boats.. Sooooo it would follow that the opposite would be
true and the like 50cc 3 and 4 or five horsepower r/c 50cc motors would be killer on a bike if one
wanted to step up and pay the price of admission..and yes a plane requires a lot of torque to turn a
prop..

 

[DuctTapedGoat]

How much is a weed eater at a thrift shop?

How much is an R/C plane motor (used, ebay, new, anything)?

That's why people use weed eaters, it's cost effective, easy to do, and there are guides on how to do it that has been proven.

I don't think you'll be pleased with the results for the cost though. But, it's your wallet, not mine. If you wanna do a large R/C motor, by all means - have at it.

 

[Wheres my dog]

Wait... I stand corrected here guys

I was thinking of small, very small engines as he first mentioned... not knowing we were talking about 200 to 400 CC engines!

Could be possible!

 

[DuctTapedGoat]

Lol, same here.

But, I'm not sure if it's a "save money" thing, or if it's a "i'm gonna do this cause I think it can be done thing". It's tough to say from what he's said. If it's the latter, there's no stopping him.