After a recent conversation with a Rascal Rides reader mentioning changing the cranks on her son’s mountain bike I started to give it more thought. That conversation inspired me to do some research.
In the time I have written for RR I’ve tended to just accept the lengths provided by the innovative companies we promote. Luckily, those companies (Woom, Prevelo, Spawn, etc) are fairly proficient at stocking appropriate sizes.
When we’ve tested a bike with cranks that are too long, we just said so, and suggested choosing a different bike. However, that ends up eliminating a few otherwise good bikes that just had inappropriately sized cranks.
Even on our favorite kids bikes, some riders might need a shorter or longer crankset for more comfort. Or, you might want to bling out your child’s bike with an upgraded carbon crankset.
Whatever the case may be, we’ve rounded up a list of the after-market crankset options for kids.
Generally, crank standards for the following sized bikes seem to follow suit or come in close. Those sizes are 80mm for 14″ bikes, 95mm for 16″ bikes, 130mm for 20″ bikes, 145mm for 24″ bikes, 155mm for 26″ bikes and 165mm for 27.5″ bikes.
Trailcraft sells a plethora of Direct-Mount chainring sizes with a 68/73mm bottom bracket and a 6mm offset spacing. Crank lengths range from 127mm to 165mm. Spacer rings and a 168mm Q-factor complete the spec list for this diverse crankset.
Buy at: Trailcraftcycles.com
Prevelo Heir Crankset
This affordable crankset comes stock on the Prevelo Zulu and is compatible with Boost spacing. 120mm, 140mm, and 152mm sizes match the needs of most children’s sizes. Direct-Mount chainrings with either 28 or 30 teeth and a 3mm offset (Boost) or a 6mm offset can be purchased with the set.
Buy at: Prevelo.com*
Spawn Brood Styx Crankset
Although Spawn sells Brood cranksets ranging from 89mm to 160mm, the smaller sets are built with a square tapered spindle and meet the needs of small riders. Once kids are tall enough for a 20 inch bike, the alloy cranks become compatible with a 68/73 BB shell and Direct-Mount chainrings.
Buy at: Spawncycles.com
Cleary sells all of their models cranksets, but we have listed the Scout’s crankset here. You will notice the shape is quite similar to Trailcraft and that is because they are most likely both Samox cranks. Offered in either 140mm or 152mm lengths and a narrow Q-factor, these cranks are ready for your little one to spin down the trail.
Buy at: Clearybikes.com*
Well, some of the other cranks listed here are built by Samox so we decided to find some of their offerings. The M7J is a carbon crankset that fits most kids on 24″ and 26″ bikes. The set has a spindle that fits a 28.99 BB shell and comes in 145mm and 155mm lengths. Like all of the others, they pair with Direct-Mount chainrings. These are spendy for a crankset, but they are carbon and reduce the overall weight of the bike.
Buy at: Samox.com
Prevelo Heir Carbon Cranks
We recently tested a set of these sweet pedal sticks and they are no joke. At 145mm, these cranks are setup to fit most riders between 24″ and 26″ bikes. Like the other Prevelo set, they are compatible with Direct-Mount chainrings and a 68/73 BB shell. 28 or 30 tooth chainrings with either a 3mm or 6mm offset can be purchased with the set. Your kids will really know you love them when you buy them lightweight carbon cranks!
Read Review: Prevelo HEIR carbon pedals
Buy at: Prevelo.com*
5 Dev R-Spec Crankset
We got to meet some of the 5 Dev team at Sea Otter this year and their products are outstanding. They make a titanium crankset that I would love to have. The R-Spec is an aluminum set that comes in larger adult sizes but also 155mm and 160mm sizes too. One can buy the set with either a 29mm or 30mm spindle and both can be purchased with a 167mm Q-factor or a Super Boost Q-factor.
Buy at: ride5Dev.com
There are other cranksets out there. It seems a lot of people are trying out the Goldix cranksets off of Aliexpress but they are also having spacing issues and threads need to be chased. I personally want to buy something that can be installed without issue. I understand the need to reduce expense but you get what you pay for.
The cranksets listed above are built with quality, durability and the rider’s needs in mind. Get out there and upgrade your kiddo’s sweet ride for them!
More Stuff You Might Like
- Your Guide To The Best Kids Mountain Bikes
- 5 Best Kids Bike Saddles
- 5 Best Kids Bike Pedals Tested and Reviewe
The Rascals are a family of three. Kristen (mom), Blair (dad), and Parker (kiddo). We started Rascal Rides when Parker was born and we didn’t want to give up our passion for biking. As we learned, we shared. Over the years, we’ve tested hundreds of kids bikes, helmets, bike trailers, and more.
Kristen is a USA Cycling certified coach and loves to share her passion for biking with other families. Blair is a bike geek, mechanic, and mountain bike junkie. Parker is our resident tester and inspiration.
If you see us out on the trail, make sure to say hi!