New Fat Tire BBSHD Build From Scratch! Need HELP Selecting Components!

[Cyb0rg d3ck3r]

I'll absolutely be doing a full build thread with tons of pictures here soon. But I'm not 100% sure about some parts, and I was hoping some more experienced riders might steer me in the right direction. Thanks in advance!

Kinda Light vs Kinda Heavy? I don't want to go 40mph, but do I want range and nimbleness? Or heavy duty with more float?

Priorities: I'm building a commuter that will spend most of its time on gravel or pavement, with the occasional singletrack/cornfield in mind. Deep snow maybe once or twice a year if I'm ahead of the plow trucks somehow, but not a backcountry trailblazer per se, nor a downhill bomber. I don't want to buy a bunch of parts and then upgrade them, and no current models really check all my boxes, so I'm starting from frame. I have a lifetime of experience on rigid MTBs and I love them, and fat tires alone are such an improvement in ride, I don't want suspension (if I find out I was wrong about that I can maybe add a suspension seat post, MAYBE suspension stem, most likely neither).

Motor/Battery: 100% going with a BBSHD, probably with a half-grip throttle and a 500c or Eggrider display, and Ludicrous controller. For battery, I will probably either try to cram in the biggest one possible, or keep 2 small ones. Probably Luna.

Rigid Frameset: Probably going with a BikesDirect level frame for cost. I was looking at a Gravity Bullseye Monster frameset, or a Motobecane Boris frameset, both $200 on Amazon (pictured). At 5'10" 170lbs, I can run either medium size (16-17") for handling or large size (18-19") for stability, both comfortably. However, the Boris has a modern geometry that might require a large's triangle for a battery. I have no idea which frame is lighter, but the Monster has hub spacing of 135mm/170mm (4" tires max, = lighter?) and the Boris has 150mm/190mm (5" tires max, = optionally heavier). I wish they were thru-axle rear, due to power level. ALMOST CONSIDERING a Surly Wednesday/Ice Cream Truck frameset for the steel construction and TA spacing, but it's another $600-800 so that's quite a choice. Any experience with either? SUPER OPEN to other suggestions too!

Wheelset: I consider "default" to be like an 80mm Mulefut with 4" Maxxis Minions. The "light" option, maybe Alex Blizzerk 70mm with 4" Kenda Juggernaut Pro? The "heavy" option might look like 100mm HED Big Aluminum Deal with 5" Snowshoes/Cake Eaters or some such? Haven't decided between tubeless or ultralight tubes yet. Definitely interested in any notable options here!

Freehub/Cassette: I want inexpensive all-steel stuff to handle the BBSHD torque confidently. Might get a wheelset through Bikesmiths with the Novatec D101SB/D102SB hubs. Cassette somewhere in the 8-9-10 speed range.

Brakes/Rotors: Noticed everyone suggests nice big/strong hydraulic disc brakes, but I've also heard only hydraulics can fail at high (ebike) temps. I was unwilling to accept "Powerful Hydraulic Disc Brakes" from BikesDirect lol. Not sure how "nice" these need to be, but I DO like the low maintenance of mechanical discs, if they'd be enough with huge rotors, maybe 200mm front/180mm rear, maybe Ice Tech? Wildly open to suggestions here, but will probably go with bb7 and metallic pads unless/until I NEED hydraulic.

Chainring/Crank Arms: We'll see. I want to see how the stock Bafang stuff lines up before I choose a Lekkie or Luna ring. I like the idea of longer crank arms but I'm concerned about pedal strike so who knows. Any input appreciated!

Derailleur/Shifter: We'll see. Not too picky here, I'll go with something serviceable. Suggestions welcome.

Stem/Handlebar/Seatpost/Saddle/Pedals: I'll basically pick this stuff up last, when the rest of the bike is pretty much done. Not sure how I want to set up a cockpit until I can see my frame size choice in real life.

Thanks for reading, I GREATLY appreciate any advice/experience/input! Once these decisions are made, I'll be starting. This will be posted on a couple different forums, feel free to chime in wherever! I can't wait to get this daily driver started!

 

[Tom@WashDC]

I'll give you some specific opinions later tonight when I get back from my ride. In the mean time, check out my build thread from 2021.

My DIY Luna Cycle Bafang HD is finished!

It's very cold outside. Snow and ice on the ground. All my parts have arrived. What better place to start my DIY build? Bike: Mongoose Dolomite Fat Tire Bike Motor: Mid-drive, Luna Cycle, Hot Rod Bafang BBSHD, 1600 Watt. My current ride is an Aventon Level with about 950 miles on it. My wife...

forums.electricbikereview.com

~Tom

 

[Tom@WashDC]

I don't want suspension (if I find out I was wrong about that I can maybe add a suspension seat post, MAYBE suspension stem, most likely neither).

I did that, suspension seat post, a Suntour. It helped a wee tiny bit, but I lamented not having the rear suspension big time. It was the height of the panedemic, bikes were in short supply so I could only get a steel framed hard tail Mongoose Fat Bike.

Motor/Battery: 100% going with a BBSHD, probably with a half-grip throttle and a 500c or Eggrider display, and Ludicrous controller. For battery, I will probably either try to cram in the biggest one possible, or keep 2 small ones. Probably Luna.

I'd wait on investng in the controller. That motor with the stock controller is pretty powerful. It will snap your chain easily if you are in the wrong gear. Adding the controller later is easy. I addded a second battery, 37.5Ah total.

Also, I did have the Shift Sensor in the beginning. Later took it off. Not necessary if you know how and when to shift.

Haven't decided between tubeless or ultralight tubes yet. Definitely interested in any notable options here!

I did not have tubeless rims on my fatty, I have them now on my Z1 and my Frey Savannah CC. Get tubeless rims, that way you can run at 5lbs psi, which is where you wanna be in the snow, sand, mud, or woods. Especially if you don't have a rear suspension. I had lots of pinch flats in the woods due to rocks and roots. I eventually solved the problem with Tannus Armor inserts. I never had a flat after that.

Freehub/Cassette:

Go with a robust hub and cassette. I went with Microshift 9 speed, steel cassette, 11-42, with matching derailleur and trigger shifter. Luna 42T Chainring. It was a good combo.

Brakes/Rotors: Noticed everyone suggests nice big/strong hydraulic disc brakes, but I've also heard only hydraulics can fail at high (ebike) temps.

My Mongoose fatty had the cheapest, crappiest brakes you could source in China! Still using them and they work real well. They squeak, they need adjustments, but they work real well. I did upgrade my rotors from 160mm to 205mm.

Chainring/Crank Arms: We'll see. I want to see how the stock Bafang stuff lines up before I choose a Lekkie or Luna ring.

You can throw away the Bafang stock chainring. It won't hold the chain. Serioulsy. I went with Luna chainring. The cranks are fine. The fatty profile should be high enough where you don't get pedal strikes.

Stem/Handlebar/Seatpost/Saddle/Pedals: I'll basically pick this stuff up last, when the rest of the bike is pretty much done. Not sure how I want to set up a cockpit until I can see my frame size choice in real life.

I added an adjustable stem riser.

You will defintiely want a front shock.

I tried the Kenda 4.5" Juggernaut Pros, running with tubes. They sucked. Sidewalls deteriorated catastrophically.

If I had to do it over again I would have gone with a rear suspension frame with 2.8-3" tires. There is no real advantage to 4" tires except on the beach. They do get a lot looks, stares, and oooh's and aaaah's though. My riding buddy had a Sondors Rockstar, clearly a better bike in every way. Nobody even noticed him. they all came up to me to ask questions about the bike and admire it. I'm convinced it was the 4" tires and wide blue tims.

I'd look in to the ToSeven motor. It has Tourqe Sensing. Once you go Torque Sensing you'll never go back to "Cadence-only" sensing. The BBSHD is nice, a real work horse, but now I have it's sister motor from Bafang, the UltraMag. Same power, same torque, but it's got torque sensing. Much, much, more enjoyable experience, better exercise, and riding control.

Looking forward to your build thread.

~Tom

 

[Cyb0rg d3ck3r]

I did that, suspension seat post, a Suntour. It helped a wee tiny bit, but I lamented not having the rear suspension big time. It was the height of the panedemic, bikes were in short supply so I could only get a steel framed hard tail Mongoose Fat Bike.

I'd wait on investng in the controller. That motor with the stock controller is pretty powerful. It will snap your chain easily if you are in the wrong gear. Adding the controller later is easy. I addded a second battery, 37.5Ah total.

Also, I did have the Shift Sensor in the beginning. Later took it off. Not necessary if you know how and when to shift.

I did not have tubeless rims on my fatty, I have them now on my Z1 and my Frey Savannah CC. Get tubeless rims, that way you can run at 5lbs psi, which is where you wanna be in the snow, sand, mud, or woods. Especially if you don't have a rear suspension. I had lots of pinch flats in the woods due to rocks and roots. I eventually solved the problem with Tannus Armor inserts. I never had a flat after that.

Go with a robust hub and cassette. I went with Microshift 9 speed, steel cassette, 11-42, with matching derailleur and trigger shifter. Luna 42T Chainring. It was a good combo.

My Mongoose fatty had the cheapest, crappiest brakes you could source in China! Still using them and they work real well. They squeak, they need adjustments, but they work real well. I did upgrade my rotors from 160mm to 205mm.

You can throw away the Bafang stock chainring. It won't hold the chain. Serioulsy. I went with Luna chainring. The cranks are fine. The fatty profile should be high enough where you don't get pedal strikes.

I added an adjustable stem riser.

You will defintiely want a front shock.

I tried the Kenda 4.5" Juggernaut Pros, running with tubes. They sucked. Sidewalls deteriorated catastrophically.

If I had to do it over again I would have gone with a rear suspension frame with 2.8-3" tires. There is no real advantage to 4" tires except on the beach. They do get a lot looks, stares, and oooh's and aaaah's though. My riding buddy had a Sondors Rockstar, clearly a better bike in every way. Nobody even noticed him. they all came up to me to ask questions about the bike and admire it. I'm convinced it was the 4" tires and wide blue tims.

I'd look in to the ToSeven motor. It has Tourqe Sensing. Once you go Torque Sensing you'll never go back to "Cadence-only" sensing. The BBSHD is nice, a real work horse, but now I have it's sister motor from Bafang, the UltraMag. Same power, same torque, but it's got torque sensing. Much, much, more enjoyable experience, better exercise, and riding control.

Looking forward to your build thread.

~Tom

Good advice on the controller, conservative on cash. Same on the shift sensor, I suspected as much.

Those Tannus armor inserts just blew my mind! Are they for tubes AND tubeless? They look awesome!

Been hearing Microshift suggested across the board with a hardened steel cassette. Probably going here.

Not sure about this ToSeven motor, I'll be throttling a LOT and I like common stuff. Interesting still.

 

[Tom@WashDC]

Good advice on the controller, conservative on cash. Same on the shift sensor, I suspected as much.

Those Tannus armor inserts just blew my mind! Are they for tubes AND tubeless? They look awesome!

Been hearing Microshift suggested across the board with a hardened steel cassette. Probably going here.

Not sure about this ToSeven motor, I'll be throttling a LOT and I like common stuff. Interesting still.

Tannus is for tube. Not necessary of if you are tubeless.