Specialized Sirrus Build Thread (BBS02 750w Kit)

xenon

Member
I decided I would install a BBS02 750w kit on my new Specialized Sirrus Sport hybrid bike. I will be posting pictures and install videos of this build for others to learn from.

Apparently the standard kit is over-geared so I ordered the HPC spider adapter to change the gearing. Does anyone have any advice for the optimal front/rear sprocket size when pairing this kit with the NuVinci 360 rear hub?

HPC Spider Adapter
http://www.hi-powercycles.com

I am considering 38t front/21t rear to maintain the proper ratios that the NuVinci 360 requires.

NuVinci 360 Specs:
http://www.fallbrooktech.com

 
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xenon

Member
I just learned that 750w electric motors are not legal in Canada. :(

Looks like I will be forced to downgrade to the 500w version of the BBS02 kit. Boooo!
 

opimax

Well-Known Member
I don't think you can tell from the outside, including authorities. if you drive respectable you will probably never have to tell!
 
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stevenast

Well-Known Member
I don't think you can tell from the outside, including authorities. if you drive respectable you will probably never have to tell!

Second that. Cops basically don't care as long as you act like a normal bike rider.
 

xenon

Member
UPDATE:

I ordered the 8fun BBS02 kit last week from Paul @ EM3ev and ended up getting the 750w 48v version (I will print a 500w sticker to stay out of trouble) with Samsung frame pack (13S, 4P, 25R cells, 47V, 9.8Ah). I also got the kit with right side half-twist grip throttle, C965 display and green ebrake push button to kill power to the motor while shifting.

I also ordered the custom 104 BCD Spider adapter from hi-powercycles to pair up with a 38T Race Face narrow/wide spider so that I can get this kit geared a little better.

The spider and adapter have arrived but I am still waiting on the 8fun kit to ship. I am very excited for this build. :)
 
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MLB

Well-Known Member
The Spider is going to push the right side out even further than normal, which is already problematic for chain alignment on a lot of bikes. I think i was told another 5mm when I inquired. FWIW
 

George S.

Well-Known Member
My order arrived April 20th, after being entered March 23rd. The package went by air, but there were week long delays to catch a flight, and a week to post from HK into the China Mails. I think it was worth the wait, for my MAC. Other problems since, not major. People like @flymeaway have done this stuff and really know the ropes. He sent me some disk spacers, which should be very helpful.
 

xenon

Member
UPDATE:

I received box 1 of 2 today. The battery was shipped separately and is scheduled to arrive on Tuesday.

I started installing the C965 display, brake levers, ebrake, etc.. and ran into a problem I never considered. My bike includes Shimano ST-EF51-7R Brake/Shifter all-in-one. While installing the supplied bbs02 brake levers with the power cut off, I noticed that I am loosing the ability to shift my rear gears!

What exactly do I need to purchase to get the shifter levers separate from the brake levers?

EDIT:
I did some reading and turns out all I need is a Shimano Acera SL-M310 right side 7-speed shifter. $20 on eBay... can't go wrong. :)
 
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xenon

Member
Another issue I ran into while installing the wiring harness.

There is nowhere to plug the ebrake button while both brake levers are used. I am guessing I need to sacrifice a brake lever in order to use the ebrake button.

It would be nice if a splitter cable was included to maintain full functionality of the kit.
 

flymeaway

Well-Known Member
I am guessing I need to sacrifice a brake lever in order to use the ebrake button.

You've perhaps read where many riders (including me) use the brake as a "cut-off"/"clutch". I adjusted the left brake cable length so the mechanical braking happens at half pull. The switch engages immediately and turns off the motor. When shifting I just pull the handle a small amount, motor turns off, shift, release brake handle.

Court J.
 

xenon

Member
Yes, I was aware of that. I just felt the button ebrake was a better solution.

I guess this button I ordered is useless.
 

George S.

Well-Known Member
This is the most discussed topic about the BBS02. Paul has his solution. Lectric Cycles makes a branded line of BBS02 with the Czech shift sensor. They say it is the complete solution. People use Nuvinci hubs or the internally geared Shimano hubs. Some manufacturers call this the complete solution.

When you build, you are stuck with making decisions. The process will take a while. You are already waiting for parts. You can email Paul and ask how to use his green button, and maybe you'll end up waiting for more parts. I'm building, and I'm waiting for parts.

https://electricfatbike.wordpress.c...-cutoff-switch-for-bbs02-from-em3ev/#more-935
 

flymeaway

Well-Known Member
Yes, I was aware of that. I just felt the button ebrake was a better solution.

I guess this button I ordered is useless.
you could use the brake button and install the left brake lever but not connect the electric switch output, use it as a normal brake.......

Court J.
 

xenon

Member
you could use the brake button and install the left brake lever but not connect the electric switch output, use it as a normal brake.......

Court J.

That's the plan.

I am pretty new to working on bikes. I usually bring my bikes in for repair/service. This was not something I wanted to get installed because I felt this was a neat project. With that said, it cost me more in tools than if I had paid a shop to install it for me.

Tools needed for removal of stock crank:
ParkTool compact crank puller CWP-7
ParkTool BBT-22 bottom bracket tool

Tools needed for installation of bbs02 motor:
16 notch external bearing bottom bracket cup wrench
Bottom bracket lock ring wrench

An issue that I did not expect came up today while installing the mptor into the bottom bracket. The plastic cable guide under my bike was too thick. I needed to replace it with a generic low profile version to get it to fit.

I picked a cheap pair of handlebar grips that I could cut in half since I am using the twist grip throttle. I also located a shop that had the 7-speed trigger shifter in stock.

I got the kit installed successfully. Now I just wait for the battery to arrive on Tuesday.
 

xenon

Member
I hooked my bike up to my fluid trainer to test out my new trigger shifter.

Turns my rear cassette has 9 speeds. FAIL!... FML... lol

I bought the bike new and haven't ridden it yet. I had no idea why I assumed my bike had 7 gears in the rear.
 

MLB

Well-Known Member
yeh, that bikes way to current looking to have a 7spd. That's what 15 years ago?
On the other hand, I've seen it suggested to use 7spd setups because that was a larger, stronger chain that the 8-10spds. With all the torque of the BBS, maybe keep the shifters and swap the cassette? you won't miss the gears.
 

xenon

Member
I ended up getting a set of Shimano Acera trigger shifters and only used the rear 9-speed shifter.

I took it out for my first ride yesterday and it performed flawlessly! EM3EV did an amazing job programming the C965 controller. Having 100% throttle only mode in every assist level sure was nice and being able to turn off assists while still having throttle is also appreciated. The power delivery was the most shocking. I've never ridden an ebike before so this was quite an eye opener. In the right gear, I could not find a hill that I could not climb with ease. Very impressive torque.

I ended up purchasing half-twist and thumb throttles for both right and left sides because I had no idea what configuration I would end up using. Turns out, the left half-twist throttle was the winner. The right side trigger shifters prevented me from using the throttles on the right side.

The only complaint I have about the kit would be the quality of the brake levers. They are absolutely massive and ugly. They remind me of the levers I had on my dirbike in the 80's. I would love to find a replacement set that is compatible with the BBS02.