Yawn.
Wake me up when a real, actual, brand, makes one that isn't designed to fail in 50 hours ride time....
Wake me up when a real, actual, brand, makes one that isn't designed to fail in 50 hours ride time....
Mongoose Jasper 24 inch fat bike at Costco Canada
It seems I forgot to cross post the breakdown review of the Mongoose Jasper 24 inch wheel fat bikes being sold at Costco this year which I wrote 3 weeks ago in the Ottawa Moutain Bike Association page. How silly of me...
You can find the geometry info on the Mongoose USA website (look for the Argus Trail 24 under kids fat bikes, its basically the same bike aside from significant component and drivetrain differences meant to drop the price by more than half). Alloy frame/steel fork, drilled single-wall alloy 95mm internal width rims, 24 x 4.0 chaoyang tires, 1x7 FW drivetrain with too big a chainring so like the Northrock XC00's needs a drivetrain improvement but there's basically no alternatives in Canada at the moment for short adults and youths for economical fat bike options. Hub dropout spacing is 190/135 so the wheels could always be rebuilt with a cassette rear hub for better gearing options, and alloy 24inch fat forks can be ordered from aliexpress.
Edit with extra info from after it arrived....
- Okay, out of the box with all the stock parts/accessories its just under 38 pounds. Frame size is 12 inches and the effective horizontal toptube length is 21.2 inches, with a 25.75 inch standover height so probably ideal for someone with an inseam around 28 inches. .
- the 24 inch drilled alloy rims are the same 95mm internal width that the 26 inch Mongoose Argus Trail, Argus Sport and Dolomite ALX get and any tire inflated on them is likely to measure greater than the claimed size (not that there are a lot of tire options in 24 inch fats).
- The stock fork is 3.5 pounds of steel, and has clearance for tires up to about 4.5 inches wide, and frame will clear that also. Not that any brands that I can think of offer such a thing, though there is the option if you have another front wheel to put a 26 inch fat fork on it, to turn it into a sorta fat mullet bike. Steerer tube is a straight 1 1/8 diameter and the frame is 44mm headset cups top and bottom.
- The handlebar, seatpost and crankset are steel. The 152mm length crankset weighs 1098 grams including crank bolts and dust caps and has a 36T ring, the 31.6 x 300mm post is 430 grams, and the 650mm width handlebar is 628 grams. I intended to replace all these parts with among other things, the stock alloy 650mm bar from a Northrock XCF, the 34T narrow-wide ring 155mm arm prowheel SqTaper crankset from the same XCF, and a 300 x 31.6 alloy seatpost from one of the 26er Mongoose fats I've been upgrading. Right there I'm saving about 750 grams off the bike.
- The tires ARE ChaoYang BigDaddy 24x4.0 and I haven't as yet bothered to weigh them since its not as if i have anything different to replace them with to even need to know that information (but the CY website claims 1400 grams for the 30TPI 24 x 4.0 wire-bead).
- The stock BB is caged ball bearings and steel cups with a steel axle. The BB shell of the frame is a non-standard 112mm so its not easily upgraded to a cartridge BB or anything external (you might make a 100mm BSA external bearing crankset for 190/197 chainline fit but you'd need 8mm of extra axle spacers to do it). Worse though is the fact the stock BB cups are unsealed where the axle sticks thru so a few good puddles, rainstorms or one garden hose and the little grease inside is coming right out. Easiest solution is to replace the stock cups with a set that have sealed ends and then pack in enough grease to not need to worry about it for at least a year (the ones I've got are even a half ounce lighter than the stock ones).
- The headset is a sealed caged ball bearing unit, but the bikes are assembled with barely any grease on their bearings. Same goes with the stock BB, no grease and the threads of the cups/BB shell weren't greased either. Hubs have the usual factory dollop of grease inside and are a bit better in that regard. I suggest dropping the fork out and then adding a healthy amount of waterproof bearing grease.
- Stock stem is a 70mm x 7 degree extension, alloy, and quite light (119 grams) with a 31.8 bar clamp. For a youth this might be too long and you might want to use a 50 or 60mm stem.
- stock pedals are adult foot sized plastic cheapos and I'm putting on some youth foot sized alloy flat pedals instead.
- Stock 7sp 14-28T freewheel is unbranded and weighs 497 grams. A Falcon Saker 14-42 9sp FW FITS inside the frame, and is only about 270 grams heavier (which it can afford after changing the bar/post/crankset/bb cups) for a whole lot better gear range. The Falcon 8 speed 13-40 FW will NOT fit though.
- Stock shifter and derailleur are from Microshift. The twist-shifter is much too large a barrel diameter for small hands to grip properly, especially wearing winter gloves and should be replaced with a thumb or trigger shifter. The rear derailleur is a short cage unit incapable of working with much larger than a 34T cog.
- The brake levers the bike comes with are fairly light but I would judge the reach to be a bit far for small hands (even after adjusting) so I will be replacing those with some tektro levers taken off the same XCFs.
- The saddle is an adult unisex 270mm length narrow racing type and should be replaced with something overall shorter in length for small riders.
Photos below are from the first one I upgraded.
![]()
![Bicycle Tire Wheel Bicycles--Equipment and supplies Crankset]()
![Tire Wheel Land vehicle Automotive tire Light]()
![Bicycle Bicycle tire Automotive tire Light Automotive lighting]()
![Land vehicle Bicycle Bicycle frame Bicycle handlebar Bicycle tire]()
![Bicycle Wheel Bicycle wheel Tire Bicycle handlebar]()
![Wheel Tire Bicycle Bicycles--Equipment and supplies Crankset]()
![Bicycle Wheel Bicycle frame Bicycles--Equipment and supplies Bicycle tire]()
![Tire Wheel Crankset Bicycle tire Bicycles--Equipment and supplies]()
![Tire Wheel Bicycles--Equipment and supplies Bicycle Bicycle wheel]()
You can find the geometry info on the Mongoose USA website (look for the Argus Trail 24 under kids fat bikes, its basically the same bike aside from significant component and drivetrain differences meant to drop the price by more than half). Alloy frame/steel fork, drilled single-wall alloy 95mm internal width rims, 24 x 4.0 chaoyang tires, 1x7 FW drivetrain with too big a chainring so like the Northrock XC00's needs a drivetrain improvement but there's basically no alternatives in Canada at the moment for short adults and youths for economical fat bike options. Hub dropout spacing is 190/135 so the wheels could always be rebuilt with a cassette rear hub for better gearing options, and alloy 24inch fat forks can be ordered from aliexpress.
Edit with extra info from after it arrived....
- Okay, out of the box with all the stock parts/accessories its just under 38 pounds. Frame size is 12 inches and the effective horizontal toptube length is 21.2 inches, with a 25.75 inch standover height so probably ideal for someone with an inseam around 28 inches. .
- the 24 inch drilled alloy rims are the same 95mm internal width that the 26 inch Mongoose Argus Trail, Argus Sport and Dolomite ALX get and any tire inflated on them is likely to measure greater than the claimed size (not that there are a lot of tire options in 24 inch fats).
- The stock fork is 3.5 pounds of steel, and has clearance for tires up to about 4.5 inches wide, and frame will clear that also. Not that any brands that I can think of offer such a thing, though there is the option if you have another front wheel to put a 26 inch fat fork on it, to turn it into a sorta fat mullet bike. Steerer tube is a straight 1 1/8 diameter and the frame is 44mm headset cups top and bottom.
- The handlebar, seatpost and crankset are steel. The 152mm length crankset weighs 1098 grams including crank bolts and dust caps and has a 36T ring, the 31.6 x 300mm post is 430 grams, and the 650mm width handlebar is 628 grams. I intended to replace all these parts with among other things, the stock alloy 650mm bar from a Northrock XCF, the 34T narrow-wide ring 155mm arm prowheel SqTaper crankset from the same XCF, and a 300 x 31.6 alloy seatpost from one of the 26er Mongoose fats I've been upgrading. Right there I'm saving about 750 grams off the bike.
- The tires ARE ChaoYang BigDaddy 24x4.0 and I haven't as yet bothered to weigh them since its not as if i have anything different to replace them with to even need to know that information (but the CY website claims 1400 grams for the 30TPI 24 x 4.0 wire-bead).
- The stock BB is caged ball bearings and steel cups with a steel axle. The BB shell of the frame is a non-standard 112mm so its not easily upgraded to a cartridge BB or anything external (you might make a 100mm BSA external bearing crankset for 190/197 chainline fit but you'd need 8mm of extra axle spacers to do it). Worse though is the fact the stock BB cups are unsealed where the axle sticks thru so a few good puddles, rainstorms or one garden hose and the little grease inside is coming right out. Easiest solution is to replace the stock cups with a set that have sealed ends and then pack in enough grease to not need to worry about it for at least a year (the ones I've got are even a half ounce lighter than the stock ones).
- The headset is a sealed caged ball bearing unit, but the bikes are assembled with barely any grease on their bearings. Same goes with the stock BB, no grease and the threads of the cups/BB shell weren't greased either. Hubs have the usual factory dollop of grease inside and are a bit better in that regard. I suggest dropping the fork out and then adding a healthy amount of waterproof bearing grease.
- Stock stem is a 70mm x 7 degree extension, alloy, and quite light (119 grams) with a 31.8 bar clamp. For a youth this might be too long and you might want to use a 50 or 60mm stem.
- stock pedals are adult foot sized plastic cheapos and I'm putting on some youth foot sized alloy flat pedals instead.
- Stock 7sp 14-28T freewheel is unbranded and weighs 497 grams. A Falcon Saker 14-42 9sp FW FITS inside the frame, and is only about 270 grams heavier (which it can afford after changing the bar/post/crankset/bb cups) for a whole lot better gear range. The Falcon 8 speed 13-40 FW will NOT fit though.
- Stock shifter and derailleur are from Microshift. The twist-shifter is much too large a barrel diameter for small hands to grip properly, especially wearing winter gloves and should be replaced with a thumb or trigger shifter. The rear derailleur is a short cage unit incapable of working with much larger than a 34T cog.
- The brake levers the bike comes with are fairly light but I would judge the reach to be a bit far for small hands (even after adjusting) so I will be replacing those with some tektro levers taken off the same XCFs.
- The saddle is an adult unisex 270mm length narrow racing type and should be replaced with something overall shorter in length for small riders.
Photos below are from the first one I upgraded.
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I'm not going to get into a debate with you on this, I realize you resell these things so you're not going to be very objective anyway.
You mentioned the lack of seals and grease on the BB and headset, one would expect the parts to fail without proper grease.
Steel bars, post and cranks...you said yourself to use it as a prybar...so disposable. What could I resell it for? $5?
A 3.5 pound steel fork on a 24 inch wheeled bike is an anchor any way you slice it.
95 mm inner width wheels with 36 spokes for a 24 x 4 inch tire are overkill and needlessly added weight for an 80 pound kid to ride in the snow. Plenty of people are running 27.5 x 3.8 on 50-60 mm rims. Probably impossible to go tubeless too.
Likewise steel bars, post, cranks, tubes etc. 38 pounds is 38 pounds. Bad gearing etc makes it even worse and that's before you even try to ride it on snow.
So basically, most of the parts need to be replaced, then you get the Costco "build quality", which I posted a pic of on FB as well (fork installed backwards)
The fact you have a garage full of parts makes it easily upgradeable. For me, not worth the $ or time, plus I admit I would need a shop to do some of the work.
So while the $389 might seem appealing....it would really be $700+ to get it setup properly, which is what you sold your built one for right?
So yeah, it was a pass for me.
Cool to see bikes in that size....but if it were better spec'd for more $ i likely would have grabbed one.. If it was more like the Northrock XCF vs the XC00.
Heck if they had brought the standard Argus Trail and priced it at about $550 ($529 USD) it might have been worth it. 2 x 8 gearing, aluminum fork, bars, post etc.
www.mongoose.com
I'm still on the lookout for a plus tire bike for my son that could do some double duty as a fat bike for groomed days.
You mentioned the lack of seals and grease on the BB and headset, one would expect the parts to fail without proper grease.
Steel bars, post and cranks...you said yourself to use it as a prybar...so disposable. What could I resell it for? $5?
A 3.5 pound steel fork on a 24 inch wheeled bike is an anchor any way you slice it.
95 mm inner width wheels with 36 spokes for a 24 x 4 inch tire are overkill and needlessly added weight for an 80 pound kid to ride in the snow. Plenty of people are running 27.5 x 3.8 on 50-60 mm rims. Probably impossible to go tubeless too.
Likewise steel bars, post, cranks, tubes etc. 38 pounds is 38 pounds. Bad gearing etc makes it even worse and that's before you even try to ride it on snow.
So basically, most of the parts need to be replaced, then you get the Costco "build quality", which I posted a pic of on FB as well (fork installed backwards)
The fact you have a garage full of parts makes it easily upgradeable. For me, not worth the $ or time, plus I admit I would need a shop to do some of the work.
So while the $389 might seem appealing....it would really be $700+ to get it setup properly, which is what you sold your built one for right?
So yeah, it was a pass for me.
Cool to see bikes in that size....but if it were better spec'd for more $ i likely would have grabbed one.. If it was more like the Northrock XCF vs the XC00.
Heck if they had brought the standard Argus Trail and priced it at about $550 ($529 USD) it might have been worth it. 2 x 8 gearing, aluminum fork, bars, post etc.
Argus Trail 24
Roll over all sorts of difficult terrain with ease on the Argus Trail fat tire bike by Mongoose. This beast of a bike provides improved stability on sand, snow, or even slick roads. And the Argus' aluminum frame makes it lighter and stiffer than ever.
www.mongoose.com
I'm still on the lookout for a plus tire bike for my son that could do some double duty as a fat bike for groomed days.
Attachments
It's funny your sig says this when the complete opposite is true.
I don't post to generate business for myself or make like I'm better than sliced bread
You posted about a bike, I wrote more than 1 detailed responses that I CONSIDERED BUYING ONE but I eventually didn't (yes largely based on your write up but 38 pounds and inadequate gearing isn't hard to spot) and provided the reasoning for the decision yet you tell me to not post in your thread.
LOL. Sure thing bud.
FYI, I just got back from Costco....they have the same 5 Jaspers on display....including the one with the backwards fork. These aren't flying off the shelves like the Northrock and rightfully so.
Too bad we can't get this deal in Canada, Fatboy 24 for $665, or like I mentioned before, the Argus Trail. The Fatboy 24 weighs 29 pounds.
Fatboy 24 | Specialized.com
So Junior wants to get rad just like Mom and Dad? Well, our Fatboy 24 has your kid's name all over it. It has all the same benefits as our 'big kid' Fatboy, only it's built on 24-inch wheels for an ultra-low standover height and kids' size. Fat is now fun for the whole family.
www.specialized.com
Amazing that the Fatboy 24 comes with 68 mm internal rims......with the same width (4 inch) tires.....it's amazing the 80 pound kids can manage on such a "narrow" rim.
As for the rest of your "educational tips" about rim width and Ottawa temps, the bloody Jasper rims are wider than 90% of the stock ADULT sized rims. Mulefut, Jackalope, Turnagain, DT Swiss, Giant etc. Its's overkill full stop, especially for a 4 inch tire. As for sealant freezing, I've had no issues riding in less than -25 degree temps. An aluminum fork (from the Argus trail) would save a pound alone.
SO THANKS FOR POSTING A DETAILED REVIEW OF THE JASPER DEEEIGHT!
And good luck with your BSO reselling business.
p.s. It's still a pass for me.
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