Recumbent Modification projects, Josh K.

[Josh K.]

Hey Folks,

Here is one of my favorite applications of an RC motor, Mid drive system. I like opening up the Rans Stratus
Frame, building in some room for Battery space, and Mid Mount motor drive. This one uses a A123 24v 20
amp hour pack, and the typical RC motor/controller configuration of the day...This is the unit I ran out at
the Portland International Speedway last year, taking second place, on half of the fuel the winner used
the year before. For me, I like the alignment of the power distribution, and center of gravity. Additionally,
using a double clutch type set up, I like being able to add in the power from the feet or motor
independently. I have been charging this bike with these solar panels as well, 150 watts gets em topped of
in about 6 hours from way flat...Geared up, I have averaged 30 mph for a few good rides last year. I used
to think 20 was plenty, but things have changed. The last photo is of a Bottom bracket drive from one of
the best E mountain bike companies out there. Nice stuff, for sure. I can ask and see if we can get some
more of these motor drives if someone is interested in getting a machine built up...These run at about 2.5
miles per amp hour of go go juice!
Custom machines Rock! Josh K.
413 695 9327

 

[deardancer3]

Chain drive on a faired recumbent. man what a machine. Can you spell FASSSSST.
ON AN Sram Dual drive? How fast would a 750 watt cahin drive take it? Legal?

 

[Miles]

Hi Josh,

How much was the Optibike drive unit?

 

[12p3phPMDC]

Optidrive, I was wondering what that giant bottom bracket was...thanks Miles.

Looks some kind of planetary based motor crank combo?

 

[Miles]

Looks some kind of planetary based motor crank combo?

Yes. http://v3.espacenet.com/publicationDetails/biblio?CC=US&NR=6296072B1&KC=B1&FT=D&date=20011002&DB=&locale=

 

[12p3phPMDC]

Miles,

I knew you would come through faster than me...

I did search myself, I promise!! :lol:

 

[Miles]

 

[Josh K.]

Not sure on the cost of the bottom bracket motor system, I will have to ask about availability and pricing.

I think they are looking for a company to buy a bunch and run them in a production unit, But I will ask and see if
we can get some of these to use in modification bikes.

Josh K.

http://www.electric-cycle.com

 

[lalaland]

Hi,
This a great forum. Lots of useful info ... wish I'd found it earlier . Matt, I was wondering where you got that large chainring in that picture with the trailer. I have the issue that pedal rpm is too slow to be of use in comparison with motor rpm. As Ive read somewhere here that running the motor slow runs the risk of burnout of controller. Currently I have 50 teeth and largest commonly available seems to be 54t. How did you figure exactly what size to use?

 

[amberwolf]

You should upload the pic to the forum directly--there is an option for this below the text box when you are creating or editing a post.

Whatever that site is you are trying to host pictures on wants to install stuff on my system if I temporarily allow it's scripts. Dunno if they just like to put spyware/adware on people's computers or if the site is inadvertently infected with something, but either way it's bad juju.

So probably more people than just me cannot ever look at your linked images, until you upload them instead.

 

[lalaland]

Cheap (zero $) web hosting is worth every penny :wink: I've uploaded the photo.
Cheers,
Lawrie

 

[amberwolf]

Cool. Now that I can see it, I want it.

There are places that custom make larger sprockets; I have seen them linked in posts but did not save the URLs.

If you are adventurous you can make your own. Giles Puckett wrote a program called "sprockets" that lets you input the number of teeth, the chain size, and the BCD (spider bolt holes) for the sprocket you need, and then print that out on regular paper at full size. Then you can sprayglue that paper onto a sheet of metal thick enough for your sprocket needs, usually aluminum since a handheld powerdrill will easily bore thru it. Simply drill out all the holes indicated on the paper, remove any rough edges, and install it and ride.

I haven't done it myself yet, but almost certainly will need to for my 'ARTOO project.

Calculating out what you need is fairly simple, at least as a rough guess. How fast in RPM do you have to pedal to keep up with the motor at speed? How fast do you *want* to pedal?

Divide the numbers as a ratio, and multiply the actual sprocket's number of teeth by that ratio. Round up or down to the nearest whole number and that is the number of teeth you need.

 

[cargo]

[youtube]cOZ-_ClKRmg[/youtube]

 

[damcard]

Wow, you have more patience then me. How long did it take to do the largest one? -David

 

[cargo]

http://www.youtube.com/user/ChrisLuxembourg

 

[lalaland]

I'd be short of a few teeth (on the sprocket) and a few fingers (on the hand) if I attempted to emulate that! I'm thinking now that maybe the Schlumpf is the best way to go. I can effectively keep my keep my 33t (for crawling home when things electrical go wrong) and have the large (2.5x) chainring that I need for when they are going right.

 

[Miles]

Large chainrings at reasonable prices:
http://www.easystreetrecumbents.com/catalog/#chainrings_parts
http://www.ligfietsshop.nl/en/webshop/cog-wheel.html
http://www.cycleunderground.com.au/chainringdesigns.htm

 

[Josh K.]

The chainring on this recumbent Rans photo, at the top of this thread, is a 72 tooth, 110 chainring, from Paragon Machine Works.

I got it from them a few years back when they were making them for the world's fastest human powered bike races...

The have the CAD files, and can crank em out for ya, just have to call and order em up. I like the chain guard that comes with it,
it helps keep the chain on the chainring, when the bike is bouncing around at high speed. I have transfered this unit to my trike right now, for my final drive, on the non drive side, mounted up to a Brake/chainring adapter.

Josh K.

 

[Kirk]

In the past I have bought custom sprockets from Pesznecker Brothers in Clackamas OR. They are on SE 102 Ave. They make a lot of things, but back in the day they were world famous for their Rhino brand motorcycle sprockets. They were all ways very friendly with the garage builders, and gave us a break on one off stuff. Now that I'm getting back into building I'll see if they still are. Or get told to get stuffed.