Basics of Bike conversion

[freebeard]

It was like watching a game of telephone. It was good to see the mid-course correction.

What are some extra points I should know about it before proceeding?

Define the use case: on/off road, open/enclosed, carrying capacity, &etc. These will skew you choices.

Then do a lot of homework. Would 20hp get 90mph?

http://ecomodder.com/forum/showthrea...tor-35003.html

The 1947 Volkhart-Saggitta had 25hp and went 90mph. It is/was a four-passenger car with a Cd of 0.17. So there's you benchmark.

[Grant-53]

See www.schultzengineering.us

[freebeard]

There are plenty of ideas on Ecomodder itself.

214 mpg with DIY aerodynamic fairings on a Honda 125cc motorbike

[Stubby79]

~33kw needed to maintain 150km/hr. 50kw will get you there in ~25 seconds.

Based on the numbers I put in. Could be considerably worse or considerably better, depending on weight and aerodynamics.

[Hilton]

Originally Posted by Stubby79

~33kw needed to maintain 150km/hr.

Thanks, Is there any formula for this calculation?

[Hilton]

Originally Posted by freebeard

There are plenty of ideas on Ecomodder itself.

214 mpg with DIY aerodynamic fairings on a Honda 125cc motorbike

Thanks for sharing it is a very useful link, However, I see a lot of mechanical + aerodynamic engineering in practice. Might be I'll go for it in future. At present, I'd stuck to the simple design.

[LibertyMKiii]

My basics on this:

Around 25HP rated motor
ESC capable of over 400 amps
A killer battery setup that can discharge high amps for over 15 seconds burst.
(probably a 34V setup? )
custom gears
very efficient aero design.

Good luck to you! This sounds expensive to me!

-Liberty

[freebeard]

Originally Posted by Hilton

Thanks for sharing it is a very useful link, However, I see a lot of mechanical + aerodynamic engineering in practice. Might be I'll go for it in future. At present, I'd stuck to the simple design.

Thanks for making it about you, I was replying to LibertyMKiii.

You have the Fossil Fuel Free and Motorcycles / Scooters subforums as well. Do you know how to use the Site Search function?

Around 25HP rated motor
ESC capable of over 400 amps
A killer battery setup that can discharge high amps for over 15 seconds burst.
(probably a 34V setup? )
custom gears
very efficient aero design.

The Buick altermotor is 20hp. But it wants 72-115V. Which means smaller cables for your 15 second bursts. Why do you want [expensive] custom gears? Make it a single speed and double the horsepower rating and uprate the cable carrying capacity to compensate.

Slam-shifting takes time and you only have 15 seconds. Drag racers were skipping gears in the 1950s and beating the sporty-car types.

Does it have to be expensive? I posted a video here about someone who broke world records on a bicycle he made from washing machine parts (allegedly):

http://ecomodder.com/forum/showthrea...tml#post564109

[Stubby79]

Originally Posted by Hilton

Thanks, Is there any formula for this calculation?

I have a spreadsheet that I input the variables in to and it does the math for me. It's the same as the "Aerodynamic & rolling resistance, power & MPG calculator" up at the top of this page under "Tools", except it outputs some more data.

Variables I plugged in were from searching on google. ~ 1.0 .cd (upright rider, unfaired motorcycle), ~8 square feet frontal area. Intentionally using worst-case values (hopefully).

[LibertyMKiii]

Originally Posted by freebeard

Why do you want [expensive] custom gears? Make it a single speed and double the horsepower rating and uprate the cable carrying capacity to compensate.


Does it have to be expensive? I posted a video here about someone who broke world records on a bicycle he made from washing machine parts (allegedly):

Gears help greatly with getting the motor into its sweet spot. As we know the torque falls on its face in higher rpms with electric motors.

Expensive is just my experience with battery arrays and electronics that can handle over 300amps.

I suppose expensive is a relative term depending on what you think is expensive

-Liberty