BB7SHD - Legendary Balfa BB7 turned fatbike,...turned E-Bike

Epyon

1 W
Joined
Jun 5, 2017
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54
Figured I'd post this up, as I think it's done.

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I got the frame, a 2000 Balfa BB7, back in '07 and built it up as a proper downhill bike. I soon realized that the geometry wasn't up to the standards of the time so I made new swingarm plates that dropped the BB height and slackened the head angle. This was satisfactory for a couple years, and the bike saw a lot of use and abuse. Eventually I started passing up the Balfa for other bikes I had built. So I decided to breath a little life into the old girl. I wanted to do a fat-tired bike unlike all others. I cut apart and rewelded the rear triangle to accommodate a 170mm hub and 3.5" tire.

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I also decided to go single speed and got the bright idea to totally change the chain system. I set up a dual chain and moved the idler closer to the pivot, all but eliminating pedal feedback. There is still a bit a of chain growth between the chain ring and the idler, taken up by a spring-loaded tensioner.

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Once again, new aluminum plates were made further altering the geometry. Now rear travel was down to around 6.75", head angle (with A2C maxed out on Marzocchi Monster T fork) was 62 degrees, BB height was 14.75".

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It stayed in this form for several years, receiving the occasional upgrade and overhaul.
..................Then I got the itch, and my knees hurt. So I decided to slap a motor on there.

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So I did have slightly bigger plans. I was going to run a Speedict Neptune 15 as a BMS. Bluetooth connected to a tiny Hipipoo J5 Android phone permanently mounted to handlebars. The Neptune also supports a speed sensor and temp sensor. I'd use the Neptune app as my "dashboard". Unfortunately the Neptune is a piece of crap and doesn't work. While on the subject of crap hardware, I also purchased a Eggrider bluetooth programmer. This at least worked for a day. Though I admit Its demise may have been caused by the extra voltage I'm running.

Speaking of voltage. My battery set up consists of 3 5s Turnigy Nano-Tech 4000mah 35c LiPos in series. Fully charged this gives 63v. As some of you may know, the BBSHD has a 61.5v high voltage cut off and only 63v capacitors. So with the help of the gurus here at Endless-Sphere I modified my controller swapping the caps for 80v units and adding resistors to lower the voltage to the controller's logic. While I was at it I replaced the shunt resistors allowing the controller to pass 50 amps. Ludicrous eat your heart out! More info in this thread https://endless-sphere.com/forums/viewtopic.php?f=3&t=83778
Some pics of the controller.

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I stripped the wiring down to the bare minimum and rerouted it out the top of the controller. I reflowed some more solder over all the power traces for good measure.

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Also, Arctic MX-2 thermal paste was added. This setup has been running strong for a month now commuting to work nearly every day (only 8 miles round trip) and for some weekend fun on the trails. The small capacity batteries only give me about a 10 mile range (with pedaling), but that's enough for now, and the light weight is nice.

Random pics........

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Parts list:
Frame - 2000 Balfa BB7
Rear shock - Fox Float CTD
Fork - 2016 Fox 40 Performance Elite w/Titanium yellow spring installed
Headset - Works Components 1 1/8" angleset -1 degree
Motor - Balfa BBSHD
Crank arms - Nimbus Venture 160mm
Pedals - VP Harrier
Handlebars - eXotic carbon 840mm
Stem - Answer -20mm direct mount w/Ti hardware
Brakes - Avid trail 7 levers/TRP Spyke dual pull calipers/Hope 220mm rotor front/Hope 205mm rotor rear
Front wheel - Weinman DH80 rim on DT Swiss 340 hub
Rear wheel - Chosen 80mm carbon rim on Chosen 12x170mm hub
Seat post - Race Face Respond
Seat - Chinese carbon
Drive train - Luna Mighty Mini 30t chainring/15t to 12t on idler (Hope freehub)/12t rear cog
Chain(s): front - Connex Wipperman, rear - KMC E-Bike specific

Future plans, I don't know really. I had a sweet set up all built up with the Neptune mounted on a lexan cover for the front of the battery box. A power switch on one side and an XLR connector on the other side for charging. I might put the XLR in and bulk charge with my Cycle Satiator, but I'll still want easy access for balancing. With no working speed sensor, or the need for one really, I'll probably remove the phone from the handlebars and the sensor and magnet from the rear rotor.
 
Great build mate! Love those old Balfa frames!

Any videos of it in action?
 
Sean9002 said:
Great build mate! Love those old Balfa frames!

Any videos of it in action?
Thanks! No vids yet. I don't have a Go Pro or anything.

fechter said:
That turned out nice.

What did you use to make the battery box?
http://www.batteryspace.com/Aluminium-Enclosure-125-x68x345-mm.aspx Heavily modified of course.

tigcross said:
Great Job. I loved the BB7 when it came out. Of all the weird stuff the industry was trying back then it was one of the furthest out there. What a perfect frame to electrify with all of that room under the main tube.
Thanks. I always loved Balfas. My first was a 2001 BB7 I got in 2003. Followed by a 2002 2-Step, a 2003 BB7, then this 2000, and another 2000. This frame is actually a rarity. One of only 50 or so. The headtube is different, many of them actually cracked, but this one has survived pretty heavy abuse under my 230 plus pounds. The milling on the tubes is different too extending the full length on the sides of the top tube and the bottom of the downtube. Also, this frame has a 73mm BB. The other 2000 I have has a 63mm.
I love how the BBSHD tucks up high. Great ground clearance.
 
Wonderful work! I've always liked the idea of having a jackshaft used as the swingarm pivot. This is the way that the Motoped is configured, but...the Motoped is somewhat heavy and also pricey.

Since I've never ridden this style of frame, is the "swingarm pivot is also a jackshaft" configuration handle in any kind of a quirky way?
 
spinningmagnets said:
Wonderful work! I've always liked the idea of having a jackshaft used as the swingarm pivot. This is the way that the Motoped is configured, but...the Motoped is somewhat heavy and also pricey.

Since I've never ridden this style of frame, is the "swingarm pivot is also a jackshaft" configuration handle in any kind of a quirky way?

It's actually not a jackshaft. The pivot point is the little M6 bolt just above the cogs. I used a Hope trials hub cassette body, attached to the aluminum swingarm plate with a M10 carriage bolt.
 
Broke my first chain today. Only half a mile from home so not too bad. Chain was a KMC E-bike specific. It broke at the quick link as expected. I knew my driveline was gonna be rough on chains due to low tooth count cogs, and being a single speed behind a BBSHD on steroids. Going by the number of charge cycles on my Cycle Satiator, I'm guessing I had about 300 miles on it.
I put a Wipperman Connex (regular, non e-bike) chain back on. Never had problems with these in pedal-bike form so we'll see how it holds up. Wipperman's quick link is definitely a better design. If/when this one fails, I'll put on a Connex E-bike chain.

I keep forgetting to take current pictures. I swapped the Fox 40's top crown for a Hope integrated stem/crown. Changed to a black/yellow saddle and black grips. I finally got around to ordering spokes and nipples to build up a new front wheel with a carbon rim (same as rear). I removed the smartphone from the handlebars as well.
 
Another little update here. I'm now successfully running at 71.4v (17s). Same Turnigy 4000mah packs now in 6s, 6s, & 5s flavors. I lowered the max current down to 45A in the config to keep the wattage about the same. I'm loving the fact that this is all still the onboard controller. Hopefully it lasts.

I also officially decided to put another BBSHD on this beast for fun in the snow..............

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I was considering a Tangent, but I'm more than satisfied with the Bafang, and it's far cheaper. I'll probably go with Multistar LiPos in a backpack, or possibly sling a battery box under the downtube. 3000+ watts, 4.7" tires, 8" of suspension travel.............................it's going to be a monster truck! Going to be heavy as well. The bike weighs 48lbs. as it is.

On a related note. Can anyone recommend an alternative to Luna for purchasing a BBSHD? My dealings with them have been quite poor. I'll gladly pay a little extra for for the slightest semblance of customer service.
 
Epyon said:
... I'll gladly pay a little extra for for the slightest semblance of customer service.

I've no experience of that particular supplier, but there seems to be a general theme of bloody awful service from e-bike parts suppliers; and I've wondered about the cause?

Is it that there is not enough critical mass to sustain a decent level of competition; or maybe with most part originating in China with all the difficulties that presents, the costs and difficulty of setting up a new business in the field is such that the incumbents simply don't have to try too hard.
 
Buk___ said:
Is it that there is not enough critical mass to sustain a decent level of competition; or maybe with most part originating in China with all the difficulties that presents, the costs and difficulty of setting up a new business in the field is such that the incumbents simply don't have to try too hard.
I may just cut out the middle man and order from a Chinese vendor. Aliexpress maybe? I'm gonna tear the BBSHD apart as soon as I get it and modify the crap out of it, so it's not like I need a warranty or anything.
 
Epyon said:
Buk___ said:
Is it that there is not enough critical mass to sustain a decent level of competition; or maybe with most part originating in China with all the difficulties that presents, the costs and difficulty of setting up a new business in the field is such that the incumbents simply don't have to try too hard.
I may just cut out the middle man and order from a Chinese vendor. Aliexpress maybe? I'm gonna tear the BBSHD apart as soon as I get it and modify the crap out of it, so it's not like I need a warranty or anything.

California ebike in Benicia has the largest selection of parts, great warranty and is a warranty repair station for a couple of resellers, besides themselves. Doug was the developer of the BBS02 100-120mm conversion kit.
 
tomjasz said:
California ebike in Benicia has the largest selection of parts, great warranty and is a warranty repair station for a couple of resellers, besides themselves. Doug was the developer of the BBS02 100-120mm conversion kit.
Yeah, I've bought some spare parts from them. Not bad at all. I wish they sold a bare motor.
 
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