Walmart Fat Bike Mongoose Beast

[exe]

While I was browsing for a donor bike on Walmart online, I came across a Mongoose Beast fat bike. There is also a review of it I found on the net with some measurements. It is steel, I would guess one would need a new fork with disc brake mount. How common are tires of this size, 4"?



http://www.walmart.com/ip/26-Mongoose-Beast-Men-s-Oversized-All-Terrain-Bike-Red/22861845

http://www.ratrodbikes.com/forum/viewtopic.php?f=1&t=70721

 

[bowlofsalad]

"How common are tires of this size, 4"?"

On a scale of 1-10, 5.6. /sarcasm.

How do you say such a thing? I am betting very few that ride ebikes use 4" wide tires. For what purpose would you use 4" wide tires? Weight and aerodynamics are important details concerning travel. Those wheels would be neither light or have aerodynamic advantage over something around the 2" range. You'll find most ebikes use tires in the 1"to 2.5" range. If your goal is a comfortable ride, I suggest suspension. If your goal relates to puncture resistance, I suggest tires made for puncture resistance (see schwalbe website and look for tires like big apple and marathon series), tire liners, and puncture resistant inner tubes.

Personally, I'd never ride a bike like that.

 

[MadRhino]

...For what purpose would you use 4" wide tires?

The bike is sh*t, but the wheels alone are worth the price they ask.

Fat tyres are good for snow and beach. You can find some very good builds here, that are fat bikes.

I wouldn't ride 2" tyres with the power that I build. All my bikes are on 2.7 to 3.0, perfect size for performance.

 

[melodious]

Those curious about the bike and too lazy to find the specs.

Rigid steel frame (high tensile?)
1 1/8" Headset (run of the mill standard) w/ threaded fork
Reviewer says "don't expect a Surly Fatbike experience, but rather, a competent light trails, beach, street machine"
Dropouts (in inches :? ) 6.25" rear 5.75" front w/spacing... 158.75mm & 146.05mm

 

[dogman dan]

The pic shows how cheese the frame is, but it would be nice to ride on the beach nice and slow. Slap a GNG kit on it.

 

[bowlofsalad]

I've never really considered riding in sand before, ever, I did it a handful of times trying to plow at high speeds through as a kid. Not only did I never make it even though a volleyball court, but the stop was always less than pleasant and I hate getting sand in my shoes. I always found it faster to just go around. Tires that fat are gonna be a real drag on the watt hour per mi/km

I guess if you are taking a trip through a desert 4" tires pay off? I have considered putting a ski on a wheel though for snow though.

The jack of all trades is master of none.

 

[Chalo]

For what purpose would you use 4" wide tires?

4" tires allow the benefits of suspension with zero extra moving parts. Properly inflated, they afford more traction than smaller tires, and they allow riding on surfaces (like sand and snow) that would stop normal mountain bikes. Like other suspension bikes, fatbikes are for expanding your riding options at the expense of some speed and efficiency-- but without the penalties of noise, mechanical slop, loss of frame integrity, and extra maintenance.

Surly was the first to widely market a 26x4" tire and a bike to fit it. Now the fatbike phenomenon is well underway as illustrated by the most recent Interbike Expo, and Surly has added a 26x5" bike and a 29x3" bike to its lineup.

Personally, I'd never ride a bike like that.

A lot of folks probably felt the same way about mountain bikes when they showed up in the early '80s.

The bike is sh*t, but the wheels alone are worth the price they ask.

It's unfortunate that the fatbike-shaped object has nonstandard hub spacing. Other fatbike manufacturers have used 135mm front and rear, or 135mm front and 170mm rear spacing.

 

[spinningmagnets]

4-inch tires are not stocked on the shelf just about anywhere, but...they can be ordered on the web, and delivered by FedEx in a week. Last I checked, they were a slow seller, but be aware that there are over 12 companies that are making fat bikes this year, so fat bikes "might" have to be ordered and waited-for to arrive, but these tires will remain available for the foresee-able future.

I will try Google right now:
beach sand riding
http://overthebarsinmilwaukee.wordpress.com/2011/07/25/fatbikes-bring-new-meaning-to-the-beach-ride/
snow riding
http://www.denverpost.com/lifestyles/ci_22616218/fat-bikes-hot-trend-cold-weather-cycling

Salsa Mukluk for Canadian snow
http://www.salsacycles.com/bikes/mukluk/

Surly Endomorph 3.7-inch, $90 each
Same place, Surly Larry 3.8-inch, $90

http://www.jensonusa.com/Surly-Endomorph-Tire

ORIGIN-8 DEVIST-8ER 26 X 4.0, $57
http://www.amazon.com/Origin8-Devist-8er-UL-Tire-Folding/dp/B007HOJBDE

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edit: When I've been bored recently, I began collecting names of fatbikes, and I figured I'd post them here when I began running out of "finds". List was getting long and I found a website for fatbikes, and the side-column has a list of manufacturers who carry a fatbike model, so I gave up looking:

http://fat-bike.com/

Here's the list I had up until I found the website with a much longer list:

3D Racing Bigfoot
38frameworks.com Hogback / Jackalope
Sun Spider AT
$1260 On One Fatty
$2450 Surly Moonlander
$3000 Salsa Beargrease
$3500 Jones Spaceframe
$3975 Moots FrosTi
$4000 9zero7 Nome

 

[neptronix]

You can get that suspension effect by running the tires at a low psi, but then you get an incredible amount of drag.

I pedaled a moonlander with the tires deflated just enough to get traction on show recently and was huffing and puffing after about 1/4th of a mile riding at maybe 10mph. Even on bare pavement, i was huffin'. Couldn't imagine pedaling one of these on a day to day basis.

Thanks but no thanks..... though something like this could enable riding in more conditions than a regular bicycle would allow. As a bonus, you could fit a 150mm hub motor back there and be the first person to die from torque induced frame failure :lol: Maybe with a little reinforcement, it could be strong though. The headtube looks weak, but maybe a gusset could toughen it up.

 

[neptronix]

http://rideonpurpose.blogspot.com/2013/03/90-of-fun-at-10-of-cost-mongoose-beast.html

This guy is saying that the bike has 170mm dropouts.

Keep in mind that most hub motors come with ~200mm axles though, so some spacers could make many hub motors work here.

 

[Chalo]

You can get that suspension effect by running the tires at a low psi, but then you get an incredible amount of drag.

Knobbies are draggy. Really soft knobbies are really draggy.

The only fatbike tire that interests me so far is the near-slick Surly Black Floyd:

The 120 thread per inch version is the only fatbike tire that might compare in speed to the 2"-2.5" street treads many of us favor. I'm eager to try it out, but I have no bike that could possibly accept it. One day I'll fix that. Until then, I'm hoping for a 29x3" version.

 

[spinningmagnets]

From "green machine", de-spoked hub, 20-Ah battery, 48V

 

[spinningmagnets]

For $200, this frame has a lot of potential. Neptronix posted how you can take one of the new 32-inch wheeled bikes, and by swapping in 26-inch tires, it becomes what he called a "mid-tail" bike (shorter than a longtail).

I like how this simple mod makes room between the seat-post and the front of the rear tire, which is my favorite spot for a mid-drive motor (just like green machines fat bike above). The triangle is still free to hold as much battery as you can stuff in there, and a mid drive can connect to the left-side, right-side or BB of the bike.

I realize the pedals would sit 3-inches lower, but that is a fixable issue with a sliding bottom bracket shell for DIY recumbents, leaving the original BB to act as a jackshaft (if desired).

One of the problems encountered when designing left-side drives is the flare in the chain stays. With 2.5-inch tires on a 26-inch wheel in this frame, the chain stays leave plenty of room on both sides, plus the stays are parallel instead of narrow at the front. This frame has a low top-bar, lots of room for a low Thudbuster...like I said, some interesting features at an affordable price.

After what Farfle and LightingRods have done with making products for existing frames, somebody needs to do something with this frame.

Somebody could water-jet a couple of swinging links that bolt onto the rear drop-outs, and use a front fork as a rear suspension. It could make the wheel sit a few inches farther back and a few inches lower to help with the low-pedal issue...

http://endless-sphere.com/forums/viewtopic.php?f=3&t=48663

 

[neptronix]

I realized something about the Genesis bike. The Genesis 'Onex' model that is a single speed, and i measured the dropouts at wally world the other day. They're 110mm internally. The upgraded 'gx7' cruiser with the same style of frame has a 135mm dropout. So i'm thinking that the genesis bike has that 110mm dropout thing going on too.

So forget hub motors. There are some 110mm rear hubs that can be used to drive the disc brake though.
http://www.choppersus.com/store/product/1095/Std-Rear-Hub-FW-Disc-BLK-32/

Green machine's bike is a dream come true.

Here's another bike that Josh K built. A real limo of a midtail!

 

[Drunkskunk]

I paid way more than that for just the tires on my bike 12 months ago. they were $120 each, and the tubes ran another $20.

The bike looks like a typical BSO, Crap quality parts built by the lowest bidder. but it's interesting. Its proof that the Fat bikes are more that just a fad. Maybe this means I can get tires and tubes at more places soon. I've had to order all parts so far. my last replacement tube i waited 6 months for.

 

[MikeFairbanks]

I think it has a lot of potential.

I just wish there were more braking opportunities.

I could really enjoy something like that.

 

[neptronix]

I think it has a lot of potential.
I just wish there were more braking opportunities.
I could really enjoy something like that.

Rear motor regen is your brake for the back.
Replace the front fork with a real fork that has disc mounts.

Problem solved!

 

[Chalo]

I think it has a lot of potential.
I just wish there were more braking opportunities.
I could really enjoy something like that.

Rear motor regen is your brake for the back.
Replace the front fork with a real fork that has disc mounts.

Problem solved!

An unpretentious framebuilder could weld on a disc tab or even braze on a set of wide-spaced cantilever bosses, for wide-profile cantilevers. The original Surly Pugsley came with cantilever studs for such use.

Using wide-profile cantilever brakes would allow you to keep the original low-cost front wheel. Relacing the original rim on a disc hub, and having the fork respaced for a standard width disc hub, would cost about as much as the bike. Buying a new disc-ready fatbike wheel ready to roll would cost even more. And then you still have to buy a disc brake, which costs a lot more than cantilevers.

 

[dogman dan]

On steel, it would be quite easy to weld on whatever you need for brakes, and spread that dropout to 135 mm.

But if you are sand riding on the beach, you won't want to go fast past the meatrack. So keeping it real simple makes sense. Rear disk mount added, and a Mac 12 t with a single speed. Don't go fast enough to need more than one rear brake. Surfboard carry rack added of course.

 

[aroundqube]

Since there is some curiosity about this bike, I will play the roll of the Troll here ( and my names not bowl ! ) by passing along some facts from a reliable source that owns one. Top tube is too short ( cockpit is too small ). 170mm rear, 135mm front fork. 47 pounds. 1 !/8" threaded stem w/22.2 clamping area . 100mm stem @ 10 degrees and fork combo is making steering twitchy. The slightest turn and the tire pulls you into the turn, wheel flop is bad. 110 mm old style BB w/square taper,using 5 bolt pattern chainring . Rims- Starcircle JP95's . Tires are taller than Black Floyds,weigh 2940 grams. BF's- 1254g. Tubes- 722g . Big Fat Larrys tires fit. So, credit is due to the source / builder ; Bighit who posts on MTBR,and redirects from there to his forum undergroundvelo dot com.

 

[neptronix]

Thanks for the heads up, dude.

 

[Chalo]

6-1/2 pound tires, wow! That's as bad as the clunky motorcycle tires some here use. Seems like it would be almost comically slow with that much unnecessary rubber. I'm not surprised about the lousy handling; that might be somewhat addressable by messing around with tire pressure.

The too-small cockpit is a result of the department store bike "one size" design philosophy that puts everybody 12 years old and older on the same size bike, regardless of body size. It's really dumb, but it allows them to sell bikes more cheaply that most buyers probably weren't going to ride anyway.

EDIT:
I found bighit's thread on the fat Walgoose at undergroundvelo. It looks like the steering qualities he complains about are encountered with Black Floyd tires installed. That's not the first time I've read similar comments about the Black Floyd. It would be nice to check it out for myself without having to buy a set of Black Floyds and a bike to mount them on.

 

[dogman dan]

FWIW, I bought my specialized with 3" tires front and back. Immediately hated the 3" tire up front, similar handling issues. Same bike with 3' in back and 2.3" up front rides real nice, but definitely doesn't float deep sugar sand as good anymore. Still get good float in the back though, so a few yards of deep stuff still rides fine.

So take off the huge front tire, and just put something a bit smaller on it.

But nothing makes the frame the right size, if you are tall. Walbikes are built for teens, that are not yet 6' tall.

 

[spinningmagnets]

A while back, someone posted an adapter that was a beefy aluminum block with two parallel holes. It clamped a separate seatpost just behind the stock one in order to set the seat farther back (*googles furiously before boss comes back...)

 

[MikeFairbanks]

I'l look into it. Around here that thing would be fun. Paved paths, grass, offroad, etc. Maybe I'll put two motors on it and go nuts.

I like the price, that's for sure.


Regardless, might as well think positively about it. No reason at all to hate on it.