Newbie from NorCal looking to do his first build

[Stone Meadow]

Hi guys...I've been lurking here for a month or so and thought I'd finally start a thread, since I'm ready to build my first ebike.

I live in rural Solano Co., about an hour's drive NE of San Francisco in northern California, where my wife and I own a business in Vacaville. I ride my unsuspended '93 Mt Shasta Backwoods MTB the 10.4 gently downhill-sloped miles from the house to work about 3 times a week, but never ride home because it's a 300+ foot climb back up to the house. I'm 58, and 195 lbs @ 5'10"...so kind'a old, fat and out of shape. Anyway, I want to be able to ride the bike home on hot summer afternoons (it gets 100+ here with low humidity in the summer) without giving myself a cardiac.

To be able to ride home from work, as well as make casual trips into town whenever I feel like riding instead of driving, I've been looking at ebikes and conversions kits for a while (on and off for a couple of years). To that end I've recently visited a couple of dealers and taken short rides on several demo ebikes (24v, 36v and 48v), as well as ridden my brother-in-law's 36v15ah falconev.com conversion bike. His bike tops out at 20, and he says he'd really like to be able to do maybe 5 mph faster for commuting (9 miles each way for him), so I am leaning towards a 48v system. There is no problem charging up a battery pack at work (hey, the boss said I could! ), and a realistic 25 mile range would be ideal for my use.

On another thread, dogman had these suggestions:

Assuming this is it;
http://www.redlinebicycles.com/archives/2011-monocog-26
it should work fine. Similar to what I use. Main drawback I see is the 33T chain ring if you want to pedal at higher speeds.
This 48V 1000W kits motor will handle enough power to get you over 40mph if you decide to go there.
http://www.ebay.com/itm/48V1000W-26-Rear-Wheel-Electric-Bicycle-Motor-Kit-E-Bike-Cycling-Hub-Conversion-/390406595360
And you aren't going to beat the value of this anywhere. And you'll get it in a week from a USA dealer.
I don't use anything but lipo, so to start I'd suggest 10ah of 12s lipo. That will get you about 28mph top speed, and ~20 miles range at 20mph. That'll cost you about $200 for 4 5ah 6s lipo bricks from HK (usa warehouse). Since you have $1k to work with I'd suggest getting a Hyperion 1420i charger for about $150 or less. And you need a 24v 25A PSU to go with it. There's ways to that for under $50 or you can just go buy one for under $100.
So that's about $600 so far.
If you decide you want to go faster, you'll need a new controller capable of a lot higher voltages. 24s lipo will definitely get you over 40mph, and the controller I use cost ~$35 shipped. And in seconds you can transform your 12s2p lipo pack into 24s1p for an 88.8v nominal pack, although at that point you may want 24s2p. I've run mine at 24s and it's not for the faint of heart. For normal riding I use 18s2p and that gets my 275lbs to about 35mph, and I rarely ride over 20mph.

My bike doesn't have the Redline's gearing limitations, and the price on that eBay kit looks promising. My bike even has a large central triangle to sling a battery pack in, so I think I'm really closing in on an attractive package (the eBay seller offers the same package in a FWD version, which would leave me with all 21 speeds, so I'm leaning towards that option). I'm still a total noob when it comes to LiPo batteries, though, so I'm hoping dogman and others can steer me towards an appropriate battery package. :wink:

TIA for the help and suggestions!

 

[sk8norcal]

have you check out this site?

https://sites.google.com/site/shelbyelectro/home

 

[Stone Meadow]

have you check out this site?

https://sites.google.com/site/shelbyelectro/home

I hadn't come across that yet, but from a short tour it looks to be a good source...thanks!

 

[dogman dan]

Your needs should be easily filled by just about any kind of kit, so you need to explore whether you would prefer a gearmotor that freewheels and coasts well, or a direct drive that needs to have some power to keep it rolling with no resistance. 300 vertical feet of hill is no sweat for any ebike, provided the grade is not much above 7%. By 10% you start to need specialty hubmotors, or non hub motors.

The yescom usa kit is a direct drive motor. DD has been my preference, because when a motor heats up, a dd sheds the heat a bit better than a gearmotor. I live in hot desert. Since your ride is only 10 miles, this won't really affect you.

It would easily get you up your hill on 36v, and do it a bit faster on 48v. A rear motor will be able to use a 7 speed freewheel, so you will keep all your gears. However, you will only need 21'st once you have 1000w of power on tap.

Battery choice, 10 mile round trip makes it well within the range of a 48v round cell A123 pack from Emissions Free. If you wanted even more range, then a 48v 15 ah pingbattery would be a good choice. Don't get a 20 ah, because by then the battery is beginning to get over large and over heavy for convenient carry on a bicycle. Another option that is in country is a battery from Chicago Electric bikes. Small and light, this may appeal to you. Since I ride a bit longer distance, and climb about 1500 vertical home, I have liked the 48v 15 ah ping.

 

[Stone Meadow]

Battery choice, 10 mile round trip makes it well within the range of a 48v round cell A123 pack from Emissions Free. If you wanted even more range, then a 48v 15 ah pingbattery would be a good choice. Don't get a 20 ah, because by then the battery is beginning to get over large and over heavy for convenient carry on a bicycle. Another option that is in country is a battery from Chicago Electric bikes. Small and light, this may appeal to you. Since I ride a bit longer distance, and climb about 1500 vertical home, I have liked the 48v 15 ah ping.

Just to clarify, it's 10 miles each way...not round-trip.

I really liked your idea of a split battery pack. It makes packaging easier and allows the weight to sit down lower. Well worth the $10 IMO. That said, I haven't made up my mind about which chemistry to go with. More reading to do and questions to ask!

 

[dogman dan]

Uhh. Duhh, what I meant not what I wrote.

Yeah, 10 ah is more than enough capacity to go 10 miles one way. charge and come back.

48v is good for 1 mile per 3/4 amp hour, including a reserve for extending battery lifespan. You'd have about 12-15 mph range at 25 mph from a 48v 10 ah cellman pack.