Mongoose Beast Fat Bike build and ideas

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WOW that's an expensive Superman sticker and new seat. Dang he's good :praise:
This is the part that makes me laugh the most, "Sanded, primed and painted rims with rust resistant paint"... The rims are not made of steel so they will never rust...
 
beast_gateway_fatbike.jpg
 
Hey, last week I bought a Dozer since the Beast is out of stock at Wally World. I like the bike so far, but the one thing I wish it had was at least a 2nd gear. Aside from lacing up a different hub that I've seen on this thread, is there any other way to do it? Maybe with different cranks, two sprockets and front derailleur?

Or should I just return it and get a Dolomite?
 
Lacing up the wheel is trivial compared to finding something that will fit. There has been endless discussion about adding gears and brakes to beasts in this forum and others on the web.

One option is the Sturmey Archer 3 speed hub SX RB3 made for the choppers ($200 just for the hub). Fits the overwide rear end of the beast/dozer. Then you need brakes. Yeah, it's just easier to buy the dolomite or a more expensive fat bike from bikes direct dot com

You could go for much lighter weight tires to make it ride easier.
Or a bigger cog on the rear hub.

3 speeds: "too high, too low and not quite right"
1 speed: always too high or too low.
 
You can do a mountain bike crank, with 2 or more rings. And a front derailer. But you will still need a chain tensioner, something like a rear derailer. BUT: then your coaster brake won't work.

A dolomite is a better option if you want gears. If you don't want gears, but you do want it easier to ride, then just change the rear cog to a bigger one.
 
Yeah, I forgot about the tensioner. Sounds like a PIA. I already put a 20 in the rear and like it for all around riding. But an even lower gear would be good for climbing or a higher gear would be fun to see how fast you could go.

I put some Haro Knee Saver bar on it, too. Perfect height for me. The only thing that concerns me about the Dolomite is the changing of the geometry. I don't know if it's for the better or worse since I'd rather have an upright stance. It's hard to tell unless you actually ride both. I've been down the high end MTB trail before and got bored with it. My ultimate goal would be to have a big looking BMX bike with gears.
 
Yeah, I forgot about the tensioner. Sounds like a PIA. I already put a 20 in the rear and like it for all around riding. But an even lower gear would be good for climbing or a higher gear would be fun to see how fast you could go.

I put some Haro Knee Saver bar on it, too. Perfect height for me. The only thing that concerns me about the Dolomite is the changing of the geometry. I don't know if it's for the better or worse since I'd rather have an upright stance. It's hard to tell unless you actually ride both. I've been down the high end MTB trail before and got bored with it. My ultimate goal would be to have a big looking BMX bike with gears.
 
The beast sits more upright than the dolomite. I rode them back to back yesterday. That being said, the dolomite feels like a lot better bike.
 
Cool, thanks. I just went ahead and ordered one. I'll have both bikes here for awhile and sort it out then. One of them will be returned regardless.
 
I got a Dolomite on Monday and just returned it today. That was quite a hassle, too. I posted a review on Walmart.com. We'll see if it gets censored since it hasn't shown up yet. I gave it 1 star. I knew the components would be econo-style, but Mongoose has redefined that. If it was cheaper than $350 I probably would have kept it and upgraded it. Pretty soon $500 - $600 will get you a Gravity or Motobecane fat bike and those look pretty good right of the box.

For now, I'll stick with my Dozer because of pure simplicity.
 
Hi I am new to the site, I have put some pictures in the wrong place of my 1981 20" fat mongoose , called the fatgoose 170, 170 being the width of the hubs.
the pics are in the intro section.
 
Ill be hanging around here for a bit as I contemplate building a fat bike out of a Schwinn Heavy Duti. If I can find used mongoose wheels and a fork I may be in business. Over at MTBR there are some nice builds as well.


I LIKE BIKES
 
Ill be hanging around here for a bit as I contemplate building a fat bike out of a Schwinn Heavy Duti. If I can find used mongoose wheels and a fork I may be in business. Over at MTBR there are some nice builds as well.
I LIKE BIKES

Are you talking about mongoose BEAST wheels? I doubt they would fit in the Heavy Duti frame. If they did fit, the chain would rub on the side of the tire so bad it would saw thru the tire. The HD frame bb is too narrow to take a Beast bb axle. Oh, isn't the HD a 1-piece crank anyhow. Check out the wheels at the ratrodbike store. I think some of those could fit. http://ratrodbikes.storenvy.com/collections/158902-wheels-tires
 
The thing about fat tires is you run really low pressure in the tires, like 8 to 12 psi. The soft tires take the bumps and that doesn't transfer the shock to the rims and spokes. If you need that rock hard tire - go fast - feel every bump - type of ride, then you go with skinny tires (<2.0") with full suspension to save your wheels.

From a wheel strength perspective, most fat bike wheels are poorly designed. The spokes run nearly perpendicular to the center plane of the wheel. You lose that triangular geometric shape that offers so much lateral stiffness in wheels. But the fat rims are so wide, they have their own anti-twisting shape so I guess that makes up for it. Breaking spokes or rims is very rare on fat bikes at any quality level.
 
PS, I've been riding my Beast on all surfaces including up curbs, off curbs, through ditches, over 2x4s, full water bottles. No issues at all trying to break the bike. It is a heavy duty bike, no doubt about that. The stock tires can take about anything except over inflation.
 

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