Figured I'd post this up, as I think it's done.
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.
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.
View attachment 19
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".
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.
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.
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.
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........
View attachment 1
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.
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.
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.
View attachment 19
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".
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.
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.
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.
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........
View attachment 1
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.