Advice on hybrid donor bike for BBSHD

calebm

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I'm new to the ebike world and looking to purchase a donor bike to combine with a BBSHD kit.  The bike would be used for my 5 mile on-road commute.  

My budget is ~$2,100 for the whole thing, which leaves me about $650 for the donor bike.  I'm looking at purchasing one of these three hybrid bikes:
Specialized Crosstrail Disc
Trek Dual Sport 2
Giant Roam 2

Any thoughts between these choices?  I have test ridden the Specialized and Trek at my local bike shops, and gotten the (expected?) advice from the guys there that I shouldn't do a conversion on these bikes because they're not durable enough, will fall apart under the extra weight/power of the motor, etc.

Would be interested in any insight you all have on this, thanks.
 
That 2100$ also includes the battery ?? I'd consider a a 500Wh battery as a bare minimum for the BBSHD. I actually think the BBSHD is more enjoyable with a 1000Wh battery
Battery is expensive. The very small battery packs that fit under seat I consider way to small... they cannot support the 30A load of the BBSHD for any prolonged amount of time and will irreversibly die of a very premature failure.
Never forget the battery is the single most important part of an eBike, and also the most expensive one. Otherwise, it will end up being a deception. Still the BBSHD is totally awesome !

All three bike looks cool. Just make sure the Bottom bracket is of the compatible kind or you'll have a bad surprise.
Read this to find out what kind of bottom bracket will accept a BBSHD and check that the 3 bikes youre looking at can accept it :
https://www.empoweredcycles.com/blogs/news/101474694-bottom-bracket-standards-and-bafang-mid-drive-motors
 
Can't say 100% without knowing road condition, your weight, anticipated speeds etc... but I personally wouldn't hesitate to convert any of those three bikes to medium-duty electric. I put a bbs02 on a very similar hybrid for my wife, and it is a great bike.
 
Thank you both for the responses.

@Matador - Yes, the budget was intended to include the battery (budgeting about $600 for that). I will check out that article you linked. I did find a short writeup over on electricbike.com where someone successfully put a BBSHD on the same Specialized I'm looking at, so that is encouraging from a fit perspective.

@footloose - Road conditions are fine, I'm in Phoenix AZ so roads are mostly well paved, flat, and straight (ie boring). I'm a skinny 6'4" 185lbs. As far as speeds, I'd like to get up to 30mph on long straights, but I expect stop lights to keep that down (ie I won't be able to cruise at 30mph for long uninterrupted distances).

Thanks again.
 
luna cycle.com sells a giant roam 2 with bbhd and 48volt battery for 1995.00. complete bike and motor. just saying.
 
slacker said:
luna cycle.com sells a giant roam 2 with bbhd and 48volt battery for 1995.00. complete bike and motor. just saying.

Which 48V battery ???
When choosing the battery, you need to consider more than just it's nominal voltage, otherwise what might sound like a great deal might not be.

For example, I can make you a 48V for around 10$, but I would not advise using it on an eBike (13S1P of old laptop cells...) :lol: . 48V by itself means nothing much.
A small 0.3 kW (13S2P) might be cheap in price, but it's not enough for running BBSHD. A waste of money IMHO, unless you limit your BBSHD controller to 15 or 20A max.
A good 2kWh 48V battery can easily cost you 1000-1500 $.
There is a wide spectrum of battery possibilities.

So 48V battery means nothing for the price without knowing other specs.
 
Understand that Trek and Specialized bikes come with a "major brand" surcharge. Apples to apples, they cost more than lesser known but equally good brands like Jamis, Marin, or Raleigh.

At your price point, I'd absolutely avoid gimmicks and frills so as to spend the budget where it counts. That means no suspension of any kind, and no disc brakes. No 650B/27.5" wheels. No 10-speed, and ideally no 9-speed rear gearing. If you find a bike at your price point without these cost-adding, non-value-adding features, then it means the other components will be of higher quality and durability.

Unfortunately, gimmicks sell bikes, and it's far easier to find a crappy $650 bike with gimmicks than it is to find a solid $650 bike without them. The closest thing my shop sells is the Jamis Coda Comp, which has nothing-special mechanical discs, but otherwise pretty good spec and 3x8 gearing. It costs $599. The next lower model, the Coda Sport, comes with linear pull rim brakes and costs $529. We sell the Linus Roadster 3-speed for $599, which would be an unusual but delightful mid-drive e-bike, at least if the chainline worked out.

A really good suspension fork and really good disc brakes might in fact make for a better mid-drive bike (or they might not, depending on your personal tastes and riding conditions). But a $650 bike won't come with really good suspension and discs; it will come with cheesy versions of these parts. Better to stick to the basics and get a more dependable, long-lasting ride.
 
slacker said:
matador, battery info on luna website. look it up and you decide.

Did check for fun.
That 1995$ base pice gets you a Panasonic 13S4P GA cells shark pack with the bike (I think you have to add taxes, shipping, and hazmat though). 48V ; 13.5Ah@0.2C(0.7A/cell aka 2.8A for whole shark pack)

In real life, the BBSHD LVC is set out at 41V IIRC. Meaning it stops when the cell reaches 3.154V.
Cruising around in economy mode (PAS 2/5) at 17-20 mph, I use around 600W (12A) --> so 3A/cell.
IF i pull 30A (for example during acceleration or going a very steep hill), this represents 7.5A/cell.

Looking at the GA graph at a 3A discharge curve (average between 2 and 4A) and at a 8A discharge curve (for acceleration/hills), knowing it'll stop at 3.154V.
The GA cells can give you real usable Ah (actually might be a little worst than that because of wires and nickel strips resistance).
Panasonic NCR18650 GA (Rated 10A, 3500 mAh).jpg

From this data, we are more suceptible to extract 3050 mAh/cell @3A/cells. ---> Real life Ah of the GA shark pack closer to 12.2Ah @ 12A average.
If you were to climb a mountain with high slope, flogging it WOT @ 30A all the time (7.5A/cell) you can expect 2400 mAh from these cells. So that would give you 9.6Ah (if you lucky) @ 30A average (unlikely you'll do 30A average).

I remember with PAS 5/5, I'd do 24 A on flat when going 36 mph and pedeling like crazy. If do that the whole ride (6A/cell), I can expect 2600 mAh/cell. So at that pace, and with the 41V BBSHD Low voltage cutoff (3.154V/cell), I'd extract 10.4 Ah from that GA shark pack.

Well not bad for a 13.5Ah pack. Gotta say the price of the package seem pretty interesting indeed. Even if I personally wouldn't chose GA cells for this setup.

Matador
 
slacker said:
luna cycle.com sells a giant roam 2 with bbhd and 48volt battery for 1995.00. complete bike and motor. just saying.


This bike above will easily do the commute that you want and more, also prebuilt for you. If you need more battery add more like I did here below later on. Just get on a bike you will love it.

55e114164b132208058d10a95fd6237d.jpg
 
Chalo said:
pull rim brakes and costs $529. We sell the Linus Roadster 3-speed for $599, which would be an unusual but delightful mid-drive e-bike, at least if the chainline worked out.

Nice bike, the olive looks stolen off the streets of Amsterdam.

EDIT wow on the citizen 3 and several "recreation" choices!
 
I inherited the bottom line Specialized Cross Trail (v-brake) and I'm thinking about converting that. It looks like a good foundation, like you were thinking.

But in your case, I would definitely get the luna cycles pre-built bike, unless of course you just can't resist the urge to tinker...
 
chas58 said:
I inherited the bottom line Specialized Cross Trail (v-brake) and I'm thinking about converting that. It looks like a good foundation, like you were thinking.

But in your case, I would definitely get the luna cycles pre-built bike, unless of course you just can't resist the urge to tinker...
Tinker and get a better build, AND the ability and knowledge to trouble shoot and repair. Getting dupport on a prebuilt kit isnt always pleasant.
 
I have heard that getting support from Luna cycle isn't always pleasant either. :mrgreen:

I agree with Chalo on this one. Buy a plain robust bike with no frills, to have the best frame to build on with the money that you have. Yet, if you are good with bike mechanics and do the maintenance yourself, you can have better value for the money buying a used bike.
 
Have you shopped Bikes Direct or Bikeisland: their scratch and dent outlet? I have two Deadeye Monsters from BD and a Gravity Sniper from Bikeisland and am happy with them all.

Ditto with Luna, I've had warranty issues that were always quickly handled and always fairly. But I've never had one of their batteries fail and I imagine that shipping a damaged LiPo back to them for a claim could get tricky from a legal sense. No shipper is going to want a battery pack with an unknown fault to enter the system, especially if it might travel in an airplane at any point.
 
Thanks for the tip on the pre-built bikes from Luna, I hadn't seen that before.  I'm 6'4" and so was hoping for an XL frame size, but the largest Luna has showing is Large unfortunately.   Plus, even if I select the available sizes on Luna's sight, it won't let me "add to cart", it's saying it is out of stock... this is happening for several of their bikes at different sizes, not sure what's going on.
 
I have 23 inch Diamondback sport for a 6'5" you might be a little short with comoly frame $100.00. The worst Fork and original tires like new. The problem for me I couldn't fit a thud buster post as that would be a giraffe. I'm looking for a frame size that a thud buster and a battery. Then a fork. I having to rethink my donor mtb frame.
 
Since you're so tall, I'd look at a 29er so you can also fit fairly big tires on it. At least 2" wide to handle the extra weight and a MTB frame is just more durable for higher speed ( and knocks ).
 
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