Fat tire E bike build help

[Valcourt24]

I am new to E bikes in general.. not to mention e bike builds. I have been deep diving through forums, YouTube and websites trying to learn and understand what I’m looking at but it is very overwhelming so here I am asking you guys for some help and guidance. I am only looking for 1 E bike to do it all as money is not infinite in my bank and also I don’t want multiple bikes at this time. I am willing to upgrade things within the platform with time but also don’t like to waist money so I do prefer buy once cry once mentality. The platform I am planning to build off of is a 2017 rocky mountain blizzard -50 fat tire bike. I plan to switch tires from aggressive studded tires to pavement road fat tires depending on what I’m using it for.

My primary GOAL for an E bike will be to use it off roading in all 4 seasons, up steepish hills at times and rough terrain that may have mud/dirt and/or snow depending the weather. Occasionally pulling a trailer to set up camps in the back country or along trail systems, most time will limit trailer pulling to flatter less hilly terrain due to what I would imagine is significant loss of distance. During these times weight will vary, I weigh 230 lbs and my gear can be upwards of 100 lbs depending on what I’m doing and how long I’m gone for + weight of bike and trailer… usually closer to 60lbs of gear for those trips. However, my primary USE with the E bike will be a commuter to and from work during nicer months through rain, sun, and small amounts of snow (being in Canada I am hopeful that means May - October) so the weight for that will be maybe 250lbs + bike. The commute to work is just over 30km (60 km round trip) with not a ton of elevation change, and mostly paved paths. Id also like to use this to pull the kids around but I know if its built for my goal then I’ll have no issues doing that… I must add this is how I sold it to the wife to let me start this rabbit hole of a project (it will pay for itself with fuel savings over time, which it will.. I hope).

In saying all this my priorities are:
1a) range … Id love to be in to 60-100 KM range (40-60 mile range) if possible.. more is better
1b) durability … I do plan to bring some spare parts with me.
2) budget
3) noise
4) speed

My current thought process is 52v 1000w BBSHD mid drive motor, open to other suggestions if the cyc pro x1 gen 4 is better or something else but remember my priority is durability and range. After that I do get quite stuck with info. A lot of different batteries from Luna, EM3ev, triangle batteries and on (willing to pack multiple batteries and or wire 2 batteries in) Not looking for cheap batteries, I want it to work. Im also not sure what gearing would be best for an E bike like this or what controllers would be best. I see egg rider v2 and their new egg rider C1, or 860c… I would like to program my system to best fit my needs at the time of riding. Id also like to adjust pedal cadence and would like torque sensing but the torque sensing is not the end all be all for me. I don’t plan to use the motor only very often, maybe just for fun or short trips but will usually pedal. Any and all help is appreciated and if you built a bike just like this I’d love to hear about your build and what you would change if anything. Thanks again. *full disclosure, I plan to post this on a few forums to reach the most people*

 

[scianiac]

When you say snow what do you have in mind, because a little bit of snow is no problem but as the snow gets deeper the power requirements start to become exponential. Using fat tires basically makes most performance worse except for snow and sand, well an I guess extreme mud but generally you can just avoid that unless you are like riding through a swap or something. So like that little bit of snow for commuting regular studded tires would be fine but back country snow could mean very deep snow that will be impossible or require a very specialized setup (I've spent this winter working on this and testing). You could have narrower wheels and tires for other times of the year though but that adds costs and at some point the compromises do start to not make sense.

I just think that trying to make a bike that can literally do everything means you will end up with a bike that is not very good at anything. Which is not to say you can't cut out a few things that aren't super important if it means improving others that are.

 

[Valcourt24]

First off thanks for the reply, and this has been a worry/consideration of mine and being new to e bikes I am open to changing from a fat tire bike but was hoping that the fat tire with a motor wouldn't make a huge difference. In terms of going around the mud for the most part is possible, I don't and wouldn't ride through a swamp with any bike but at times through fields and paths that aren't on trails the ground can be quite soft, especially with rain and or snow melt in fall and spring to the point even when walking you sink in a bit. In terms of snow and commuting to and from work I don't plan on being in more then 2-3" unless there is a freak snow fall. Where I am hoping to be later in the year there can be large amounts of snow 1-2' or more but at those times of the year I have come to terms with the e bike not being practical or safe so id be looking to ride it in 0-12" of snow of all different types, hard, wet, fluffy if possible.

 

[Chalo]

Range works against speed; speed works against durability and budget.

My suggestion is a 48V BBS02, with a 42t Bafang chainring, 12-46t 8-speed Microshift Acolyte drivetrain, and spend the weight and money difference between that and BBSHD/52V on more battery capacity. Use one of the very affordable, high capacity 44V automotive modules if you have the stomach for installing your own BMS.

Fat tires, like over 3", work strongly against range and performance both. So don't fall for it. The only kind of snow they work well on is groomed cross-country ski trails anyway, and those folks will hate you for screwing up their trails. Get your wheels laced up to some 29" rims and use 2.25" to 2.8" tires. More range, more performance, equal or better ground clearance, and you'll look 30 IQ points smarter instantly.

 

[Valcourt24]

Thanks for the reply, I guess I should had clarified, speed isn't really a concern for me. All motors will be faster than I am lol.

In terms of BBS02 I worry about over heating and torque in the back country. Do you not think that would be an issue for the bike with substantial weight in less than ideal areas and on hills? If not, it is something to consider.

I have not thought of installing an automotive module before, Im always up for a challenge. how much of a benefit would it give?

so from the two replies so far neither is going with fats. through fields, off trails and up hills is there not much benefit to a fat vs say a 2.8" tire?

 

[Chalo]

In terms of BBS02 I worry about over heating and torque in the back country. Do you not think that would be an issue for the bike with substantial weight in less than ideal areas and on hills? If not, it is something to consider.

BBS02 gives better torque per amp and more pedal-alongable RPM. If you want range, you will stay away from max power, which is the only advantage BBSHD gives. Keep the thing in a gear where you can pedal nice and fast, and it will run efficiently and cool. Lug it down in too tall a gear, and you can burn up either one.

I have not thought of installing an automotive module before, Im always up for a challenge. how much of a benefit would it give?

Great advantage in terms of cost, quality, performance. Disadvantage in terms of packaging.

Here's an example, choice of 48V (design voltage for BBSXX) or 44V (better match to human pedal cadence):

48v Audi Q5 PHEV modules, Zero Miles Samsung Cells | JAG35.com Jehu Garcia DIY Powerwalls Lithium Ion Batteries EV eBike eScooter Emergency Solar Off-grid

PLEASE READ THE DESCRIPTION CAREFULLY. Shipping to Lower 48 USA states only via Ground Shipping. No shipping to PO Boxes. No international shipping including Hawaii, Guam, Puerto Rico. Non-USA customers click here. EV modules with high quality Samsung cells! These 48v 37Ah 1.78kWh li-ion modules...

jag35.com

so from the two replies so far neither is going with fats. through fields, off trails and up hills is there not much benefit to a fat vs say a 2.8" tire?

None whatsoever. It's only extra weight, extra rolling resistance, extra cost, and the burden of looking stupider than necessary.

 

[Valcourt24]

You've given me a lot to think about on this topic, thank you. I'll do some digging and more research, appreciate the starting point. Since I have you on this topic reconsidering fat tires, would you ever consider something with a built in motor such as a M620/630 or something of the sort or do you believe in the more customization options for something like the bbs02. I had not given one much thought prior but now that I might consider a 2.8"tire these might be some what of an interest as well. Like I stated originally I'm very new to all this so nothing is off the table until a bike is built.

 

[Chalo]

would you ever consider something with a built in motor such as a M620/630

Never. A built in motor with a proprietary frame fitting not only prevents you from trying other motors, but it depends on the manufacturer's commitment to supporting their standard with replacement parts indefinitely. I trust that commitment, well... not at all. It's primed to disappoint you sooner or later, and waste your invested money, time, and refinement.

 

[Valcourt24]

Ok, that makes sense and kinda why I hadn't considered it previously. But you never know as bbs02 was ruled out early for me but you've definitely given me some food for thought and a days worth of research haha. Appreciate the help as I look to build a bike. I'm sure ill have a lot more questions in the future.