Chainring Selection:

28 Tooth- For easiest climbing in mountainous areas
30 Tooth- Best for most flat terrain

(2 customer reviews)


Have us set up your bike tubeless with color matched tubeless valves and Orange Seal tire sealant!

Dropper Post Install – Have a KS LEV Si 75mm dropper post pre-installed on your complete bike. Special price this month!!!

SKU: BS20 Category: Tag:


January FLASH sale on Blue Sky 20!  Winter is here, that means this is the best price of 2023 in the dead of winter! 

Special Build - LAVA, Green Turquoise - $1499,  HOT PINK and BLUE just $1399! 

PRO Build - LAVA, Green Turquoise - $1899,  HOT PINK and BLUE just $1799! 

Quality takes time, this bike is built just for from the frame up you in Fort Collins, Colorado.  We ship globally all over the world via FedEx for those out of the USA -  shipping calculates once you put your address in our system WITH postal code.

Our PRO level builds are shipping - just a few wheelsets left!   These have the NEW Stans Crest MK4 1050 gram wheels!  Complete bikes are starting at just 18.5 pounds set up tubeless! (note silver decals on the 2023 Stans Crest MK4 wheelset, not color matched)

This is THE lightest 20" hardtail you can buy right now.  A lighter bike is a faster bike!  Super light components include our new TC30 carbon fiber suspension fork, superlight wheels, and alloy spindle direct mount crankset.  YOU select chainring size based on your area.  Built to order just for you in Colorado.  WATER BOTTLE COMPATIBLE TOO!  One of the only in the category which takes a water bottle. See below for water bottle options.

You've been asking for a 20" bike from Trailcraft, and the time has come for our Blue Sky 20 to meet the young riding world!  If you want to give your kid the absolute best 20" proper mountain bike to create a life long riding partner from the earliest possible stage - this is the bike. Our Pineridge 24 was the first premium high-performance bike to hit the market and putting more kids on the top step at the local races, and we are taking the same premium approach with the Blue Sky 20.  This is a fun, playful, super flickable bike for all types of mountain bike riding.  Race it, take it to parks, or just have an awesome bike to trail ride with your family.  Next level big-kid performance is achieved with high-quality top shelf level components and category-leading bike weights.  Hang with your big bro or sis on this 20" machine - because it is a machine, it's not just another heavy 20" kids bike!

All of our bikes are assembled in Fort Collins, Colorado from the bare frame up.  This means you get to configure the bike you want in three color options, two build level options and two chainring size options to best suit your local terrain.  Rims come taped and are tubeless ready - we can set them up tubeless for you if you'd like to be about 250 grams lighter from the very start.

Click on Features, Specs, and Geometry to learn more.

Want to go a bit more custom or full custom on this build?  Contact us!  We are a small family business focused on building the best kids mountain bikes possible.  We truly geek out on this stuff, just see our Instagram page for some of what we are doing as well as our custom builds page.  We bring our frames in from Taiwan (un-assembled/not built) and we build each bike per order in Fort Collins, Colorado with US labor.  Since we don't import "complete bike in box from Asia" like pretty much everyone else does, we maintain a very high-quality control.  You can be proud to tell your kids they have a unique bike which was truly built to order from the frame up!

"Once in a while a bike comes along and blows your mind, this is one of them. Getting this bike to 19 lbs puts it lightest in class for 20 inch hardtails. Adding amazing geometry, phenomenal fork and a top quality build makes this bike worth every penny if you are a family that lives and breathes mtb.-Colin, The Bike Dads

See The Bike Dads Blue Sky 20 Review for a great video review.

Water bottle compatibility:

with the
Also, the Fidlock Twist 450ml setup works well.  This is a non-traditional mounting system, but might actually be easier for kids to operate.  The bottle cap hinge does barely contact the frame, but isn't an issue for removing the bottle.




The 20 inch bike is the one where bike weight matters!  Each frame is hand built in small batches with double butted 7005 aluminum tubing, super clean internal cable routing (no snags!), forged dropouts, and post-mount disc brake mounts both front and rear. Our Blue Sky 20 starts in the low 19 pound range with the Pro Deore model.  Low bike weights are achieved through higher quality component selection.  Small touches like our new lightweight 127mm Trailcraft aluminum spindle direct mount cranks (with your choice of 28 or 30 tooth narrow-wide style chainring) is just one part we spec as an example which helps keep weight as low as possible.

Wheelset Options:

Blue Sky 20 Pro model get our Stans Crest MK3 Custom 1050 gram wheelset.  Superlight 370 gram hubs laced to 20-inch Stans Crest MK3 rims are taped and ready for sealant.  Ashima 85 gram 160mm rotors a lightweight stoppers!

Blue Sky 20 Special build model gets our own 20 spoke Trailcraft wheelset and 96 gram ultralight Avid rotors.

- Rotors selection is one of the items often overlooked by other brands 20" bikes, our goal and spec selection is to keep wheel rotational weight as low as possible. The super low rotational weight of both wheelsets is very important to young riders just starting out, or more experienced riders trying to get to the next riding level.


TC30 air sprung suspension 80mm fork! This is the lightest 20" fork available with high mod carbon/alloy lowers, hydraulic lockout and preload adjust.  Our own TC30 20" fork (combined with the BIG tubeless tires) really works and smooths out the choppy terrain for more control while fighting off fatigue. This allows longer rides with your young rider!

Component Level Options:  

Pro model 1x10 group adds a Sunrace 11-36 cassette.  Pro level package includes Shimano Deore brakes, Shimano Deore shifter, and Shimano Zee rear derailleur to keep weight low and performance high.  Our custom 127mm Trailcraft direct mount 1x crankset with ultralight aluminum spindle and 26, 28, 30 or 32 tooth narrow-wide style chainring YOU select to create the best bike for your terrain.

Special Build Level 1x10 components featuring Shimano Zee rear derailleur, Sunrace 11-36 rear cassette, Zee 10-speed rear shifter, and Tektro hydraulic disc brakes. A great package to keep weight low, performance high, and the budget in check!  Our Special Build gets our custom 127mm Trailcraft 1x crankset and 28 tooth chainring.

The end goal - to build the lightest production 20” trail bike. Nothing more to modify to make it lighter because we've built your kid the best bike with the best components so you can spend more time riding.

(Note pedals are included!)


MODELSpecial Build
Pro Build
FRAMEBlue Sky 20 7005 Series Aluminum
Blue Sky 20 7005 Series Aluminum
FORKTrailcraft TC30 1425 grams, carbon lowersTrailcraft TC30 1425 grams, carbon lowers
HEADSETTrailcraft Precision Sealed Cartridge
Trailcraft Precision Sealed Cartridge
Shimano Saint 10 speed
Shimano Saint 10 speed
SHIFTERShimano Deore 4100 10 speed
Shimano Deore 4100 10 speed
BRAKESShimano MT201 HydraulicShimano Deore 6100 Hydraulic
CRANKSTrailcraft Direct Mount 127mm, 28 or 30t optionTrailcraft Direct Mount 127mm, 28 or 30t option
Trailcraft Alloy
Trailcraft Alloy superlight
GRIPSTrailcraft Lock-On
Trailcraft Lock-On
STEMTrailcraft, Length: 40mm
Trailcraft Superlight 70 grams, Length: 40mm
POSTTrailcraft 30.9
Trailcraft Superlight 130 grams, 30.9
PEDALSWelgo M21 Aluminum VP Composite with metal pins
Sunrace 11-36
WHEELSETTrailcraft 20", 1350 grams alloy hubs
Stans Crest MK4 20", Chosen Superlight alloy hubs 1050 grams
TIRESKenda Booster 2.2" 400 grams
Schwalbe Rocket Ron 2.25" 450 grams or Kenda Booster 2.2" 400 grams
Estimated Weight20.2 pounds tubeless18.75 pounds tubeless

*COVID parts availability advisory: The bike industry is currently having trouble keeping up with demand in these strange times. Standard builds purchased from the website might include unavailable parts at which point we will replace them with equivalent parts (and upgraded parts in some cases) due to supplier availability. Please reach out to us directly if you have any questions or would like to ensure your build includes any specific parts.

2 reviews for Blue Sky 20

  1. johng-9538

    If you want the very best kids’ 20” bike on the market, this is it! We bought the Blue Sky 20 in the Pro Build and couldn’t be happier. The components, geometry, weight, color selection and ability to customize options make this bike stand alone in the industry. Combine that with the outstanding, family-run operation and custom, customer service with Brett and Ginger that help with all details along the way, and you have a seamless process to give your kid their next dream bike… and the bike you always wish you had at this age. It climbs, shifts and brakes like no other and you’ll find it hard to get your kiddo to stop riding. Our family loves to bike and think the purchase was well worth it. We ride hours vs. minutes now and the overall quality keeps you riding and looking for the next series of trails to explore. You will not be disappointed!

  2. Kevin Purvis (verified owner)

    Got my daughter on a Specialized Riprock 20″ (7 speed, disc brakes), on her 5th birthday. It was OK, but she was trying to keep up with 6 & 7 year olds and burning out quickly. I broke down and got the Blue Sky 20″ four months later. Fantastic change, top reason I bought it was the weight and there was an immediate improvement on her climbs and overall riding endurance. The weight also made the bike more nimble and maneuverable for her. Lastly she benefited from the additional gear range. This is the best bike out there for the size.

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Additional information


Pro Build, Special Build


Blue, Hot Pink, Lava, Neon Green, Turquoise

Chainring Size

28T, 30T


Geometry - Blue Sky 20(millimeters)
Seat Tube Length-Center to Top270
Top Tube Length (Horizontal)445
Top Tube Length (Actual)443
Chainstay Length340
Bottom Bracket Heightxxx
Seat Tube Angle (Actual)73 Degrees
Head Tube Angle68 Degrees
Wheel Base864
Standover Height508mm or 20 inches

Size Chart

Approximate Age5-8
Minimum Inseam21 inches
Height Range3'9"- 4'2"

Customer Rides