assembly tests of the transmission complete with electric motor
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Another Knucklehead, built via castings, as a Draw-Tech design, upscaled
- Thread starter Foketry
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electric motor for starting
Compatibly with the dimensions allowed by the project, this is the most powerful engine I have found.
It is a 12-24 volt drill motor, 895 low speed model: 3000 rpm at 12V, maximum torque of 5.2 kg Cm, 6000 rpm at 24V, maximum torque of 10 kg Cm .
Engine speed is further reduced 3 times with toothed belt transmission.
A one-way bearing between the belt drive and the crankshaft prevents the electric motor from being dragged when the engine is running
Compatibly with the dimensions allowed by the project, this is the most powerful engine I have found.
It is a 12-24 volt drill motor, 895 low speed model: 3000 rpm at 12V, maximum torque of 5.2 kg Cm, 6000 rpm at 24V, maximum torque of 10 kg Cm .
Engine speed is further reduced 3 times with toothed belt transmission.
A one-way bearing between the belt drive and the crankshaft prevents the electric motor from being dragged when the engine is running
Oil pump and deep stick
For the oil seal I used O-rings instead of the brass rings foreseen by the project
Milling of oil pump gears
For the oil seal I used O-rings instead of the brass rings foreseen by the project
Milling of oil pump gears
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One of the mistakes I made while building this engine , note the rear cylinder inlet cam with the red arrow.
In the drawing I did not put the negative sign in front of the degrees of rotation, the result is that this cam is out of phase, the other 3 are ok.
I discovered this by manually rotating the engine, the rear cylinder intake valve was completely out of phase.
Several hours of work wasted , lesson learned, check out the drawings !
In the drawing I did not put the negative sign in front of the degrees of rotation, the result is that this cam is out of phase, the other 3 are ok.
I discovered this by manually rotating the engine, the rear cylinder intake valve was completely out of phase.
Several hours of work wasted , lesson learned, check out the drawings !
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Calculating the cam timing on a V twin takes some thinking. First of all you have the angle of the cylinders. Then there's the fact that the intakes are inboard and the exhausts are outboard so it's not just a matter of adding the cylinder angle to the timing events.
peterl95124
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"check drawing thrice, measure twice, cut once" 
!!!
!!!
Fuel tank and CDI ignition box
The tank is made of aluminum, the box is 3D printed
The same box also contains the peristaltic pump that supplies fuel to the carburetor, the excess fuel returns to the tank.
I can regulate the fuel flow via a voltage regulator. ( 12 Volt)
The tank is made of aluminum, the box is 3D printed
The same box also contains the peristaltic pump that supplies fuel to the carburetor, the excess fuel returns to the tank.
I can regulate the fuel flow via a voltage regulator. ( 12 Volt)
Just be careful with the silicon tube in the pump. Hydrocarbons in the fuel will make the silicon swell that is why you have to use Tygon type tube for fuel lines on 4-stroke models if running on petrol.
Same reason fog buster lubrication systems that use these pumps need to run fully synthetic coolant.
Same reason fog buster lubrication systems that use these pumps need to run fully synthetic coolant.
Yes I know this problem, silicone tubes are not compatible with gasoline.
I kept the pump immersed in gasoline for a week, the tubes became softer and sloppy but it still works. I don't know for how long yet.
Thanks for your advice, I will replace the silicone tubes with Tygon tubes
It is when they start to disolve and that gets carried into the carb needle that things get worse.
Regular RC Engine Tygon is much too hard to work within the pump, they do make a specific one for Peri pumps but not so easy to come by in small amounts
Regular RC Engine Tygon is much too hard to work within the pump, they do make a specific one for Peri pumps but not so easy to come by in small amounts
The Knucklehead is running
Looks fantastic and sounds great. You really work fast. - Terry
It really does look and sound great !!
I noticed that you started it with a drill, Are you not done with the starter or was the motor not strong enough?
Beautiful work !
Scott
I noticed that you started it with a drill, Are you not done with the starter or was the motor not strong enough?
Beautiful work !
Scott
What an incredibly nice piece of work, and runs superbly !
Contrats and hats off...............
.
Contrats and hats off...............
.
from casting the parts to the amazing finished and running engine, top notch thread, thanks to share !
so many things to learn here!
so many things to learn here!
Tidza
Member
I have two engines using the same peristaltic pump. I run them on methanol, which is compatible with silicon hoses, no problems a couple of years on. I add a little Castro R for lubrication as mineral oils don't mix.
I worked quickly because I followed your very complete and precise posts.
Thanks for your valuable work
The electric motor that I installed cannot rotate the crankshaft.
I was hoping that by powering it with 24 Volts it could start the engine, but a higher reduction ratio is needed.
I am waiting to receive a planetary gearbox to increase the torque, in the next few weeks I hope to start the Knucklehead via an electric button.
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What has been said, again.
Beautiful engine.
Fantastic Build.
Starts and Runs Well.
Sounds Great.
I'm looking forward to the push-button starter.
--ShopShoe
Beautiful engine.
Fantastic Build.
Starts and Runs Well.
Sounds Great.
I'm looking forward to the push-button starter.
--ShopShoe
