Budget BBSHD Dolomite ALX build by a noob

[Ridefreak]

This is my first post on here but I've been lurking awhile. I figured I'd share my build since I got most of the ideas and info for it off here. I retired from a career that included everything from Navy electronics, working in a semiconductor FAB to critical power in hospitals and data centers. The electrical aspect of an e-bike is very straight forward to me, the bicycle side of things are new. Since I don't know any better I chose to approach it from motorcyclist POV, this build might not conform to some of the norms.

I also happen to live right next to a huge chunk of desert with literally a 100sq miles of trails, dirt roads, dunes and plenty of sand. Much of it's too soft for a regular bike with narrow tires and even a 3" tire would be allot of effort sometimes. I normally ride dirt bikes, dual sports and adventure motorcycles, bicycles are a new area for me but I'm right at home on 2 wheels.

This was going to be a budget build so it ruled out the the higher end bikes and a used Fat Tire bike is pretty rare around here. With that in mind I picked up a 35# alum framed Dolomite from Wally world. I know, it's a big box store and all that entails, I figure I can address the bike's weak points as it becomes necessary. Goal was cheap, light weight (within budget constraints), mid drive and a decent battery. Where I'll be riding nobody cares if you spin the back wheel or how many watts your motor is.

Fresh out of the big box


The ergos on this bike weren't cutting it for me, I didn't care for the mtn bike bars nor the seat. Those got swapped out which improved the riding position and comfort significantly.



Next it was over to Luna for a 120mm BBSHD and Eggrider display. I picked up a 52V 20AH triangle battery and 4A charger online. The motor install was a breeze, it took longer to make the wiring nice then it did to swap over the components. I've been doing my homework and the build included a shift sensor.

The battery fit the frame like it was made for it. The bottom bracket is 120mm so the motor fit nicely w/o any spacers.


The chain line wasn't bad but could be improved and I knew it needed lower gearing, I needed to see what I ended up with before ordering anything. It'll be getting a Lekkie 40T with the 20mm offset and it's associated motor cover, the cassette is an 11/34 8 speed. The Lekkie will be a hit to the budget but I ride enough motorcycles that I know I want the drivetrain to work correctly w/o any compromises if possible and I know correct gearing makes all the difference off road.
It gets all the gears now and shifts normally so I'd like to keep a similar chain line, the Lekkie should improve that a couple MM compared to the stock chainring and give it some decent torque while keeping the motor spinning up in it's happy place.



It doesn't look like it but there's 6mm of clearance between the flywheel and the chain stay. The 46T chainring is a little closer to the chain stay but there's room to fit the 40T in there. Everything fit surprisingly well.


So far I'm pretty happy with the build, no drama. Eventually it'll get some inexpensive suspension forks, the better gearing and a decent suspension seat post. There's likely going to be some weak points but I'll deal with those as they come up. I got everything online, had it built 2 weeks after ordering the first part and I'm at $1700 w/o the future upgrades. It rides and runs nicely for being an inexpensive bike, this build couldn't have been easier.



Thanks for reading.

[73Eldo]

Looks like a nice ride with a nice detailed write up that I'm sure others considering a similar build will really appreciate. You probably have to go pretty far to find snow but have you got in any sand yet? Those tires and the BBSHD power should go through that stuff pretty well.

[Ridefreak]

I just got back from the first real ride, 24miles. I knew going in with the large stock chainring the chain is too short in the lower gears, 2nd gear has the derailleur almost horizontal so 1-4 were such that I didn't want to torque it up in the lower gears. Everything was mostly 4-8 gear, it has tall gearing. It'd do about 35mph flat out on pavement with 20psi i the tires pretty easily. It needs some finishing touches and I expected that. Half the ride was urban and the rest desert, it needs a suspension fork and a suspension seat post, at that point I think it'll be great for my plans handling wise. I'm not hitting jumps. Today I was throttling most of the 25mile ride pretty hard just to see what it's do, and run the battery down so I could cycle it. It scooted along very nicely. Especially in undisturbed sand, it's a really smooth ride and you can carve the sand at a 15-17mph speed with no drama. Those balloon tires are perfect, they ride on top of the sand all the time, I'm used to motorcycles that will drop into the sand when slowing down and you have to deal with that or ride around it. The FB stays on top of the sand all the time and as long as you aren't trying to make it climb a big soft dune it cruises on them well. It wasn't very hard to make the bike go faster in most situations then it had any business doing. I got the stats on the ride from the eggrider, 25mi distance, Avg speed 14.8 mph, ride max speed 39.77mph, I used 13WH out of a 20, 16mi of range left at todays usage. I'm really happy with the eggrider, programming is a breeze and the app and all it brings to the game seems well worth it. It was a breeze to setup.

[73Eldo]

I'm in the 250lb ballpark and on my fat bike I have a 42t front ring and 42 on the back and for my fat ass I consider that a minimum. I can climb a moderate hill in the MTB park mostly on throttle and go through fresh snow or loose sand. My street bike is still a 42 up front but 36 is the biggest on the back and its fine for the streets because if there is a hill I can usually get enough speed to make it up. Offroad or in the sand you can't always get the speed up so you need the gears.

The Lekkie 42 is about the same offset as the stock 46. The Luna Eclipse has another 6mm plus really tall teeth so I don't think that would fit your setup without some spacers. Its expensive but maybe worth considering the Lekkie 40? With its included spacer you can get 3 different offsets and its only slightly larger than the gear case so it looks like that would let you get tucked in a lot closer and maybe gain a better chain line? The Lekkie 40 is extra expensive because they say you also need their special gear case cover. Some have reported not needing it so do your research. Other thing to consider is maybe going to the 40 will mean you don't have to change your rear gears so you spend a lot up front but some of that is offset by not having to spend it on the rear.

[Ridefreak]

I'm in the 250lb ballpark and on my fat bike I have a 42t front ring and 42 on the back and for my fat ass I consider that a minimum. I can climb a moderate hill in the MTB park mostly on throttle and go through fresh snow or loose sand. My street bike is still a 42 up front but 36 is the biggest on the back and its fine for the streets because if there is a hill I can usually get enough speed to make it up. Offroad or in the sand you can't always get the speed up so you need the gears.

The Lekkie 42 is about the same offset as the stock 46. The Luna Eclipse has another 6mm plus really tall teeth so I don't think that would fit your setup without some spacers. Its expensive but maybe worth considering the Lekkie 40? With its included spacer you can get 3 different offsets and its only slightly larger than the gear case so it looks like that would let you get tucked in a lot closer and maybe gain a better chain line? The Lekkie 40 is extra expensive because they say you also need their special gear case cover. Some have reported not needing it so do your research. Other thing to consider is maybe going to the 40 will mean you don't have to change your rear gears so you spend a lot up front but some of that is offset by not having to spend it on the rear.

Thanks for the info, I ended up ordering a Lekkie 40T as well as a suspension seat post and some forks. I went with the 40 for it's increased offset, it's pricy but think it will help me improve the driveline. The CR is lined up with the 2~3rd smallest cog. Most of the other (lower) geared options appear to have less offset then the BBSHD's CR.

I'm having some issues with the chain hopping off the CR when coasting over rough terrain, even in a higher gear that's lined up decently. I'd really like to make that a thing of the past. I'm told a clutched derailleur will help with that, I'm pretty sure this one I isn't, it's a Shimano Tourney TX series which is a an entry level component, looking at its specs they don't list it as having a clutch. I'm not against using a small chain guide mounted right as the chain enters the CR, our dirtbikes have used something similar for years.

So far I'm pretty happy with it. To end up with a solid setup I knew there would be some dialing in needed and optimizing everything, that's part of the home build process and something I enjoy. I've done similar things to motorcycles over the years and typically end up with a much improved result.

[73Eldo]

I don't have clutched derailleurs and don't have issues with chain drop. Mine are older Deore so much higher quality than yours but still no clutch. The stock chain ring was pretty low quality and not a narrow wide. The Lekkie is a high quality narrow wide so it should make quite a difference plus drop you several gears which should really help the sand power and hill climbing. It will cut into your top speed but hopefully not too much.

[Ridefreak]

Thanks Eldo, I'll probably end up ditching this budget derailleur eventually, I figured if the clutched unit is preferable It'd make sense to go that route when it's getting changed anyway. I'm not in a rush and I'll wait and see how the narrow wide does.

[73Eldo]

Ya see how the ring does and what the new gearing does for you. A lot of people spend a lot of money changing parts without getting some miles on to see what they really want or need. I know my builds didn't go how I wanted and I had immediate plans to replace a bunch of major parts but after some riding I kinda changed my plan and didn't end up riding how I thought I would so the original changes would not have been worth it.

Do you have a freewheel or is it a cassette? If the gearing isn't what you want yet going to a cassette may end up being where you need to go but its not an easy upgrade because the hub has to change. If you can't build your own wheels that may mean replacing the wheel. At least in the north its off season now so many shops have pretty good deals on labor because they don't have that much work.

[Ridefreak]

It's got a cassette with steel gears, 11/34 gearing, the derailleur is the most obvious cheap componet back there. it's entry level shimano. I saw it sold separately for $16 bucks so that tells you what I'm dealing with. I was finally able to get a longer chain installed, the 46T chainring compared to the fat bike's small CR meant the chain was too short. Now I'm able to use 1st and 2nd gear.

I've been changing a few parts for sure, a suntour seatpost and forks are the comfort upgrade. I didn't really like the mustache bars I selected, the bend was ok but they were too narrow, I'm not a big fan of the more straight mtn bike bars. I had a set of bars from my Triumph 800 that fit on nicely and have a sweep I'm more comfortable with, very similar to the bars on my motos and they're about 25mm wider then the mtn bike bars.





I feel like the bike is ready for some longer testing, I'd like to do some range tests and some easier gravel riding to test a couple programming changes, plus just get some more miles on it. The initial PAS current surge is a little stronger then I'd like and I'd like to dial back the pass current at higher pedal cadences, it's running away a little at higher speeds. It's not bad but I've been reading up on the issue and think I can dial it in a little better. So far so good!

[73Eldo]

Thats good its got a cassette but bad that its already an 11 if you need more top speed once you go to the 40. At least if you need lower gears for any reason with the cassette you easily can and most of the better derailleurs will do at least a 40t if not a 52.

[Ridefreak]

I don't see myself needing allot of top speed, 25 or so would ok, the extra torque is more important to my use which is 95% dirt roads and sandy areas. The easier unassisted pedaling would be nice too.

[Ridefreak]

Did a bit of riding yesterday, the bike did well, no surprises and the limitations were things I anticipated (gearing/suspension) and planned to rectify. Very happy with the results.

[Ridefreak]

I added a couple mods to the bike, a cheap air fork and a Lekkie 40T chain ring.




The 40T required a different backing plate. There's a slight removal of material near where the housing bulges at the motor's pinion gear, it's a small amount and only took a few min with a Dremel. It cleared the chain stay fine so I was able to get the setup's full offset. It definitely has allot more torque in each gear and the top speed took a hit but it's fast enough. Haven't gotten any off road time with the new gearing but I tested out the fork yesterday on some flowy single track. The fork is nothing special but it made a big difference with roots and other stuff on the trail, much less deflection and the front raised about 120mm so the steering angle is more relaxed, That was a nice benefit to me, it slowed the turning a little bit IMO the steering didn't need to be as steep as it is stock. Feels more like one of my motos now.

[73Eldo]

Cool. For about 10 seconds I was thinking how nuts you were to spend that kind of money on a bike that cheap but then I think about my walmart bike where the current tires cost more than the bike did. We won't even talk about how much I spent on the BBSHD and battery, and fenders, and rack, and seatpost, and and and.......

[Ridefreak]

Thanks, it was a fun build, learned allot since I'm not a bicycle guy. I'm happy with how it turned out for the $ spent, it's been enjoyable to ride.

Out here in NM we've got allot of BLM land that's open to about anything you want to ride out there but a good sized chunk is only ridable on a fat bike. Out here a FB is more of a dual sport bicycle then a mtn bike is.

There;s everything here from 9K' mtns to miles of local desert.


I'm going to try and test it out in this area tomorrow.