Adding breaks to a Mongoose Dozer?

[galkadanz409]

so i'm putting together parts for an epic E-bike project, iv got the motor kit, assembling the battery, and have what may be a decent budget host bike (to start with) budget is extremely tight, i'm trying to build the most "bang for the buck" bike

the kit i have is a cyclone 3000w mid drive
battery: custom assembled 6P13S Boston power 4400mah 12 amp contentious per cell, with 60 amp BMS
Bike: a Mongoose dozer 26'' 4 wide fat bike

after looking over my components if realize that the crank arm that has a fixed sprocket welded to the arm is to be replaced by a free wheel. making the coaster break unusable,
this is my second build. first was a Chinese ebay 1kw hub kit, great experience. poor quality parts.

the bike itself doesn't look to have a whole lot of options for other breaks. i don't see any mounting for disk on ether the rims or the frame. there is the usual "V" break mounting point. but is there options for fat bikes?
fat bikes cruising @ 30+MPH with a heavy load on board at that? also money is tight. so id like to avoid putting $300 breaks on my $80 bike...

 

[docw009]

The 4" rims with V-brakes on my Walmart Kent fatbike were horrible. I don't know how good your brakes work, but mine didn't when it was a pedal bike at 10 mph. This is no dig on v-brakes. The V-brakes on my 28mph mid-drive mountain bike give me great confidence.

I replaced the front fork with one that had disk brake tabs.I bought a $20 aluminum bracket off ebay to mount a disk on the rear. Here's the ebay details on the rear bracket. It's not ideal because it mounts the caliper upside down, but it's best one I've seen so far.

Since mine is a rear motor, I had to cut a slot in the adapter to fit the 12mm w-motor axle. Otherwise, a regular bicycle axle like yours should just go thru the hole. I still wanted a reinforcing arm, so I strapped mine to my torque arm.

In hindsight, I should have bought a better bike because I replaced everything, but what got me started was the $99 price. I wouldn't have ever gone near a fatbike if I had to pay $300 or more for the entry fee.

I used a cheap generic Chinese disk brake on the rear, around $22, because it had adjusters for the pads on both sides. I needed that adjustment. You'll need a cable and a brake lever too. Do you get an ebrake lever with your motor kit?

The front disk brake conversion cost me $60 for the fork, and $24 for Avid BB5 parts, but I also changed out the head set/crown, bars, and stem. Didn't have to do that, but I wanted better quality.

 

[galkadanz409]

all the money id be putting into retro-fitting this thing it would be cheaper to just try to sell it off and buy a mongoose dolamite/terraX from Walmart for ~$220 that include selectors and breaks installed.

 

[docw009]

all the money id be putting into retro-fitting this thing it would be cheaper to just try to sell it off and buy a mongoose dolamite/terraX from Walmart for ~$220 that include selectors and breaks installed.

Good thoughts. You're right. But you still got those heavy tires. Well, you would in any low cost fat bike.

 

[Chalo]

There are no V-brake posts on a Mongoose Dozer. There is a hole in the seatstay bridge, but I doubt there is a caliper brake with long enough reach to get to the rim. The hugest caliper brakes I'm aware of can barely make it around a 3.5" tire on a 45mm rim. To make matters worse, the painted rims will interfere with braking until all the paint is worn away.

You could make drum brakes or band brakes work, but not all that well, and getting them set up could cost you more than the crummy bike is worth. Same goes for swapping the fork for one that has disc or V-brake mounts on it.

I say you'll be better off starting with another bike. Preferably not a Mongoose or any other kind of department store dumpster fodder.

 

[galkadanz409]

problem salved. just found a dolamite on cregslist for $150. came with a very nice seat and lights as well. $30-50 in goodies alone! anybody want to buy a dozer for cheap? lol