Mongoose Dolomite - Low Budget, Long Range DIY Build

[BraveMan]

Hello DIY Builders,

I decided its time to share my experiences and lessons learned on my first build. My goal was to build a capable, reliable bike with a decent range and level of power to keep me entertained I want to start out with a Thank You to the participants of this forum. The articles and follow-up posts on this forum went a long way in educating me on the correct choices to make to ensure I would not be disappointed with the final product.
I wanted to build a Fat Tire Bike for a number of reasons:

• I wanted to build a platform I could ride in any terrain and any weather; on road and off road.
• I wanted to reduce/eliminate flat tires wrecking my fun.
• I wanted to ride in the Wisconsin snow.
• I wanted to reduce my falling and crashing on the trails and tricky terrain.

Because this was to be a Low Budget build, I chose the Mongoose Dolomite as the platform to build on. The low price of the Dolomite made it far and away the best bang for the buck in the Fat Tire World. The downsides to using the Dolomite are the bike is heavy to begin with, the braking performance is less than stellar and some of the components used are the cheap, bargain basement variety. The upsides to using the Dolomite are the amazingly low price (less than $250), rugged construction, great fit and finish and ease of modification (using standard size components).

I chose the Bafang BBSHD 100mm mid-drive system as the drive for its reliability, programmability, ability to handle higher voltage (58V) batteries, availability of spare/replacement parts and ease of installation (no frame cutting). After 100 miles I am not disappointed with the system’s performance so far. (Ask me again when I get 10x the mileage on it.) I chose the factory ‘off-road’ performance tuning.

Lastly, I chose a Joyiisi 58V 24AH Rack Mounted battery pack so give the bike all day performance (over 1400 watt/hours). The system came with a 5 amp smart charger, an aluminum rear rack (which the removable battery keylocks onto) a proper Battery Management System and a built-in rear taillight. The higher initial voltage of the system eliminates any sag in performance as the battery charge depletes. A built-in Multi-LED charge indicator gives me a second method to check the pack’s charge level.

I ditched the stock Grip Shift mechanism & replaced it with a Shimano Trigger shift, tuned the brakes up (trued & deburred the rotors and aligned the calipers) added a Rinsten style seat Spring, Kung Fu handlebar grips and added blingy pedals, insulated 'water' (coffee) bottle, Rack bag & toolkit. Bottom line: I ended up with a capable, enjoyable and unbreakable ride for under $1800.00, including all the modifications and bling added to it.

[Gizmo350k]

Your build is amazing sir. You mentioned riding in any terrain/weather. Im building a similar 58v battery kit with vruzend that will be rack mounted like the one in the picture.
Is the battery in the blue bag? or in that black box looking thing above the rack?

...what measures are there for waterproofing in the event of heavy rain? a series of plastic bags and a drain hole? lol

[BraveMan]

The battery is under the blue bag (the rack has a lower level below the bag). I've taken no extraordinary measures to waterproof it. The battery stays surprisingly clean and dry.

I did encase all the exposed wiring in shrink tube, especially under the motor. I did get caught in one downpour; so far, so good. I worry more about the drive as its so exposed.

[Gizmo350k]

Awesome. I will do likewise with heat shrink and hope for the best :)

Did u have to reroute the cable for your rear derailleur to not run between the bottom bracket frame and the BBSHD, to where I see it now?
I have a much more vintage american style frame that has the two cables running under the bottom bracket, where im sure it will interfere with the unit once installed.

If i never bought the 68mm already i would definitely try to replicate this build!

[BraveMan]

All the cables were routed up high; I didn't have any issues with the existing cable routing. I DID have to modify the existing kickstand bracket to allow clearance for the wiring. Time spent with a Dremel tool . . .

[Jay Aitchsee]

Braveman, thanks for your post.
Please see my post here, where I spec'd out the bottom bracket and chain stays of my Dolomite. I haven't been able, yet, to proceed with my build, but from my specs, I concluded, that there would be little room for the left crank arm to clear the chain stay if the 100mm BBSHD were used. Apparently, you found this not to be the case. Could you discuss the clearances you found using the 100mm motor? Thanks.

[Gizmo350k]

I remember folks who built using the Mongoose Dolomite and Fatboy, using the 120mm versions of the bbshd in order to clear chainstays etc

[Jay Aitchsee]

I remember folks who built using the Mongoose Dolomite and Fatboy, using the 120mm versions of the bbshd in order to clear chainstays etc

Yes, that's what I thought from the measurements I took: Here

[BraveMan]

Definitely go with the 120mm. I had to trim the BB to make the 100mm work.

I posted some pics on your thread. Let me know if you need additional details.

[B7smith]

Did you have to use shims with the 120mm? What chain ring did you use? Thx!!

[Gizmo350k]

I'm now considering the Dolomite for my future dream build. 120mm was offered on a CYC. I had no idea. Fun times are definetely ahead.

[Wali R.]

Hey BraveMan!
NewbieDIYBuilder Wali here;

You must be my brother from another mother!

My first built was on the XSPEC 7 speed folding MTN bike. Using a Violamart 1500w kit (Top speed was between 55-60mph)w/a 48v battery.
From knowledge learned here & from Micah of Ebikeschool.com(INVALUABLE source of E-Bike knowledge Thanks Micah!!)
I've started my second build and like you I also just purchased, six hours ago, the "DOLOMITE" from Amazon.
($351.00)

Now you're gonna wanna be sitting down when you check out the below photos of the Custom-built rear hub motor. I'll give ya a moment to take it all in LOL



As is it's rated for 120km(74mph) but I'm having it built to produce 129km(85mph top speed)!
I'll be having all the welds on the bike reinforced of course.
Did you see the amount of Torque this Beast puts out?!
At this speed, my state law requires that it be registered as a "E-Scooter",
have Insurance and driver's license
to use on highway roads.
I got the builder to stamp the words: "E-Scooter Wheel"
on the side of the hub. ( A suggestion from the law)
Ah yes I've continue to do my homework/research. Lol
I'm also having a 3-pin connector added to the controller
for my HWBS

[Gizmo350k]

Amazing!! I will be calling the tax office to get a learner's liscense soon, that is some INSANE specs @_@
You will need custom spokes for the rear wheel?

Does anyone have a link to good hubs for these giant 4" tires? lmao
Awesome stuff.

There is another thread with Mongoose Malus where i am taking in information as well.

Might build a hybrid based on all the info I'm getting from you Wali. Does your controller have regen?

[Wali R.]

I have to check w/manufacturer on Regen feature (thks for the heads-up) The builder will install the motor on the appropriate wheel having 10G spokes

[Wali R.]

Can you see the photos of my Glamping gear? It's saying it's Unapproved

[Wali R.]

You're looking for the hub motor for the fat wheels correct? In that case use the vendor I mentioned in my photos: SURINGMAX. SEARCH aliExpress for him. Here you can have a hub motor build to your desire speed. You tell them if you just want the motor or install on a wheel; a complete conversion kit or specific parts thereof. Like in my case I ordered the 3 pin connector for the HWBS to be added to the controller as well as specifying the desire for the programmable BlueTooth sine wave color TFT display and programmable controller enabling me to program both via my cell phone! You really can have exactly what you want here.

[Wali R.]

My incomplete bike trailer.

Why all this Need for Speed you ask?, I'm planning on living semi off-the grid
on BLM land/National Parks. Pulling a DIY bike trailer I build from WikeBike.com
loaded w/gear to support "GLAMPING" camping. Photos to follow. (8'x5')
trailer manufacturer in Canada (AWESOME company for pre- made bike trailers to DIY kits)

As I'm planning on dividing my time on both sides of the Colorado River
(Arizona/Cali) the need for speed is needed as I'm be leaving from Florida.
The following photos are some of the camping gear and bike accessories I've just purchased from Amazon
Tell me what you think guys.


.

image widget

[Wali R.]

Top left: Silverfire Tent Dragon stove w/built in oven (as a chef this stove has NO equal on the market! Due to its 2nd burn chamber feature, that burns up Co2 emissions etc. Results: no telltale chimney smoke, and more eco-friendly. Check out the video at Silverfire.com

20L Self-contained black water toilet
12v AC/DC Car refrigerator/Freezer
5gal solar powered shower bag
5M Yurt 4- Season Glamping Tent