An interesting approach to electrifying a recumbent

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reikiman
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An interesting approach to electrifying a recumbent

Saw this on power-assist

http://www.wisil.recumbents.com/wisil/shumaker/default.htm

Rather than go with an existing conversion kit -- he described them all as overly large and overly inefficient -- he used some R/C vehicle parts such as a tiny brushless motor that runs at over 2000 watts.

strawhistle
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Re: An interesting approach to electrifying a recumbent

this sounds like an alternitive to hub motors You should invite the designer to join V is For Voltage , He has a fresh prospective !! Later

thank GOD I wake up above ground !!!!

jdh2550_1
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Re: An interesting approach to electrifying a recumbent

Wow - that's an impressive sounding motor and if I found the right page it retails for somewhere around $140...

John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.

sandorszabo
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Re: An interesting approach to electrifying a recumbent

When I emailed a friend who's into R/C the link to Shumaker's recumbent project he sent back the following link as inspiration for his fantasy bike:

http://www.icare-rc.com/plettenberg_predator.htm

To avoid the flipping-over-backward problem I suggested he just design a sturdy mount to point the motor backwards with a caged pusher prop and... WOOSH.

andrew
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Re: An interesting approach to electrifying a recumbent

That motors amazing. Any idea of the price?

[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri

Mik
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Re: An interesting approach to electrifying a recumbent

That motors amazing. Any idea of the price?

Yep, amazing!
That goes for so many things that are coming up recently - the possibilities are endless if we get our act together and stop destroying the basis for our survival on planet earth (or at least stop destroying the basis enabling us to leave the planet in a viable state...thats us not the planet...)

It almost seems like the hyper-exponential growth of the computer industry is being replicated in electrical engines...

That would be just too nice, because in 10 years time you would be able to drive an 18-wheeler interstate with the power out of a AAA cell!

Hat off to the person machining all those parts for the recumbent bike - it makes me want to buy more tools and learn to use them!

A dreamin' Mr. Mik

This information may be used entirely at your own risk.

There is always a way if there is no other way!

recumpence
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Re: An interesting approach to electrifying a recumbent

Hey Guys,

Thanks for the kudos on my bike. I have put alot of thought into my bike and about 60 hours of labor so far. It has been alot of fun to say the least.

I have it running now. Check out the web site for more pictures and a thorough description of everything.

So far, the only issue is the primary belt skipping under hard accelleration. However, that may be a good thing because I think I would break something in the driveline if the belt did not skip.

It is currently geared for 30 mph top speed. I am regearing it this week for 40 mph.

According to my data logger, it pulls 3,000 watts under the hardest accelleration. This thing really pulls hard! I have to be very careful with the throttle to keep from skipping the belt.

I will most likely make a slipper clutch for it to protect the driveline. Other than that and gearing it up a touch, it runs great! I have put about 30 miles on it and it looks like the bike is good for 20 to 25 miles on a charge depending on how it is used (leaving 20% to 25% capacity in the pack to protect the cells).

Matt

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Mik
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Re: An interesting approach to electrifying a recumbent

Hey Guys,

Thanks for the kudos on my bike.

Matt

Congratulations!

Well done, a great read.

Any estimate how much labor and cost would be involved to produce a small series of power unit kits, once the bugs are known and fixed?

Mr. Mik

This information may be used entirely at your own risk.

There is always a way if there is no other way!

wanders
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Re: An interesting approach to electrifying a recumbent

So far, the only issue is the primary belt skipping under hard accelleration.

For timing belts such as you are using, skipping means one of two things:

1) An under-specified design (hopefully, you went though the horsepower tables when you designed your transmission) or

2) Significant under-tension in the belt. This kind of belt takes a significant amount of tension to avoid cog jumping. You may need to increase the tension.

BTW, Matt, thanks for all the writeup. I have really enjoyed your effort, and especially your willingness to share the design and fabrication process, and I know that many on several blogs have also enjoyed it.

However, for the sake of completeness, you may know that a similar kind of design has been running for quite some time. Brad Hori did a quite neat effort on a much higher end recumbent than the Actionbent / China Mascot design you are working with. He used a lower power motor and a different approach to the transmission. Have a look at:

http://www.evalbum.com/1262

You are to be congratulated on your design, which should be much more cost effective.

Regards to all, and thanks again, Matt, for sharing your design effort,

Willie

wanders
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Re: An interesting approach to electrifying a recumbent
So far, the only issue is the primary belt skipping under hard accelleration.

For timing belts such as you are using, skipping means one of two things:

1) An under-specified design (hopefully, you went though the horsepower tables when you designed your transmission)

FWIW, I checked on the horsepower references for timing belts. I don't know what the width is on your belts, but the indication is that for the several KW application of power, the XL belt is a bit undersized, which might explain the cog skipping. According to this chart:

chart.jpg

you may need to upsize your primary drive belt, as an XL maxes out at just over one horsepower. I know of a source for Gates-type GT2 pulleys and belts at very reasonable prices and materials (i.e. aluminum) if you need them.

Willie

recumpence
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Re: An interesting approach to electrifying a recumbent

Thanks for the input.

I know the XL belt is under sized for this application. That is why I am running a HTD belt for the secondary reduction. The XL belt on the primary side is there parts to protect the driveline. I would rather snap pr skip that belt that trash something more substancial.

I plan on going up to a another HTD 5mm belt for the primary reduction once I make a slipper clutch for it. For now, the belt skip keeps me from hammering the driveline too hard. :~)

Matt

Recumpence

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