View Full Version : Hey Guys!

09 September 2011, 0127
Last April I was bumming around Kitsap County looking for a part time engineering job, and was introduced to the crew at Manzanita Micro. They hired me on, and it didn't take long for me to get bitten by the EV bug, with all the enthusiasm that the staff has for electric vehicles. You step into Rich's office, and you better have about three hours set aside to listen to his colorful war stories. He might even take you out in the Fiero and smoke the tires a little bit!

Anyways, I'm looking to build an EV based on Skeezmour's 1999 YZF600r. I'm trying to do it as my senior design project, so I don't have any project definitions outlined yet, but as the school year starts to take off I'll be able to nail those down.

I'd like to see ~120V and ~400 max amps, and about 100 miles of range. But, with a college budget, we'll see how that all pans out. In the meantime, I'll keep working my butt off at MM and save up as much cash as I can!

I'm hoping to use this forum as a resource of information as I start to outline my project.
Thanks El Moto

09 September 2011, 0733
Welcome to the forum. Working at Manzanita, I would guess Gene is going to be a great resource. But I would suggest reading through the numerous build threads here. There is some great information and discussion of why certain decisions were made. A common theme is reducing your range and speed requirements once you see how expensive things can get. Also, take a look through the classifieds. There is an AC20 setup for sale right now.

09 September 2011, 0818
Welcome to Elmoto and Manzanita (I do some contract stuff for them here and there from Portland). I know Gene and Rich (and Clarice and Stephen) fairly well, they're a great group and I think you'll like it there. Rich sure does have some funny stories.

First you should get some sort of budget, because if you don't limit it from the beginning it will almost always get larger.

The AC20 system would be a great setup for this motorcycle, along with some of those headways that Manzanita sells. I'm building a Honda VFR with Headway and an AC20, but my first revision was lead acid and a brushed DC motor, so let me know if you need anything.

100 miles is a tall order, and don't expect the pack to come cheap. You'll need somewhere right around 10kwh of storage, which doesn't fit easily in a bike.... unless it's Lipo. Just keep that in mind. For a college budget I suggest that you might look at some Lifepo4 and get some decent range (40-60 miles) and upgrade later. You'll get your feet wet and see what may be needed.

09 September 2011, 1013
Welcome Banny77.

Please remember:
- we love project pictures
- be nice
- have fun
- respect your elders and eat your veggies

(OK, that last one is bogus ;))

09 September 2011, 1052
welcome to the forum Banny - pictures please cause i carnt read...

09 September 2011, 1155
Hey Banny77,
Yeah, what they said.
Also, 100 mile range is not trivial. Range is the most stringent of criteria for elmoto's. Depending on your average cruising speed (I assume between 35mph and 65mph) and mission profile (like, how much start/stop action, how much acceleration etc), aerodynamics, efficiencies, roll resistance and what not, your bike is going to use up something between 75 and 200 Wh per mile. Thus, a 100 mile range requirements means your batteries will have to deliver something between 7.5 and 20 kWh. Factor in a limit on depth of discharge and capacity loss because of Peukert effect, and you're looking at a battery pack rated anywhere between 8 and 30 kWh. Can't do that with any type of lead batteries (my under-construction-bike's AGM battery pack is rated 6.5kWh and already weighs 150kg - and it's going to give me 4.0kWh under my mission profile) so you're looking at some form of lithium chemistry. 120V means 70Ah to 250Ah rated capacity... expensive.

Of course the above is all back-of-an-envelope calculations...

Nevertheless, for initial calculations, find the lowest range you're going to accept and start working with that. Upping the range later on is way less difficult than getting incredible range from the get-go. I dropped from 100km to 50 km range to keep things affordable...

Looking forward to your project outline.

09 September 2011, 1552
Thank you for the replies and encouragement! After some consideration of your input, 100 miles does seem a bit ludacris. Google Maps tells me that it is about 50 miles round trip to work and back, so I guess that I would need a full-to-flat range of 65 miles, in order to not kill my pack. I am considering going with the Headway 10ah (2p initial, 4p later on) or the CALB 40ah (1p). I'm probably going to be going with a 6.7" D&D, with a kelly or new Alltrax controller.

Here is a pic of the rolling chassis sitting in the lobby at Manzanita:

Thanks again for all your help!

09 September 2011, 1610
you'll need to do more than that for Ah.

you'll need ~7.5 or more kwh, as I'm guessing you'd need highway speeds. 120V is about 38 cells in series (121.6V nominal). With 20Ah of headway, that's 2.4kwh, with 40Ah of headway or calb, that's 4.8kwh. No where near what you'll need. Motorcycles get 100Wh/mile or lower at speeds less than 45mph, above that, expect to start to see an exponential increase after about 50mph.

Start thinking 60+ Ah in your pack of 38 cells in series.

10 September 2011, 1417
And if you can charge at work, you only need a 25 mile range.

Nuts & Volts
10 September 2011, 1429
And if you can charge at work, you only need a 25 mile range.

Like Manzanita would allow that!!! hehe

Anyways I can easilly get under 100Wh/mile on my 430lb 89 katana at any public road. There is no amount of stop and go traffic that will put me much higher than 100Wh/mile. At 45mph constant I can get about 85wh/mile and maybe lower. Hope this helps you with your numbers. Your bike should be about the same weight, but may have better aero.

10 September 2011, 1518
Are you kidding :) Rich takes it as a personal challenge to see just how fast he can get a pack charged safely. There is nothing like pulling out the 225 amp charger to get you back on the road quickly.

Nuts & Volts
10 September 2011, 1531
Are you kidding :) Rich takes it as a personal challenge to see just how fast he can get a pack charged safely. There is nothing like pulling out the 225 amp charger to get you back on the road quickly.

Just making a joke man!! Haha it would be an honor to charge at your facilities sir

10 September 2011, 1814
Looks like it will be a fun project, especially since you work in EV heaven. :) If you have a bucket list of motorcycle related parts you need for your bike let me know I have a shop full of useful things I can bring you up as a donation to the cause next weekend.

11 September 2011, 2107
Thanks for the offer Brutus. Not sure what I'll need yet, as Gene told me he has a box of parts hidden away somewhere. Just waiting on the title to the bike, and then I'll start throwing some models together in SolidWorks.

As an aside, I am doing most of the heavy fabrication/welding work at Manzanita, so if you guys need anything built, let me know. I also have access to a machine shop down the road, but we don't have the CNC mill hooked up yet so I'm limited to doing stuff on the manual mill or lathe.

14 September 2011, 0716
So last night I was tooling around Walmart, and noticed that they are selling lawnmower batteries for very cheap. The only specifications I could find on them was that they were 12v, 250 cold cranking amps, 350 amp max, and 13lbs each. It seems like I could get close to my goals with 10 of these, and only be about 10 lbs heavier than a 40ah CALB lithium pack.

I know that lithium is all the new rage, but are there any disadvantages to a lead acid pack?

Does anybody know the know the amp-hour rating for something like this? I think I saw somewhere (http://www.diehard.com/products/lawn-and-tractor) that it could pull 230 amps for 29 min.

Thanks guys

14 September 2011, 0737
I'm pretty sure those kind of lead acids are useful for cranking motors over, meaning short bursts of high current. If people use lead acid, they usually use the "deep cycle" ones that are meant to be discharged more. But lead sucks, so stick with lithium.

14 September 2011, 0741
Yeah, those are U1 size cheap starter batterys (13 lbs). A real AGM deep cycle U1 would weigh 10 pounds more (~24lbs). Those would give poor performance and last a dozen cycles....maybe. B&B and Powerstar make good EV 35AH AGM's.