Q: Can FATWHEELS be used on a multi-speed bike that has a derailleur?

A: "Yes" - all of the FATWHEELS kits are designed to accommodate bikes with derailleurs.

Q. Can FATWHEELS be mounted on Tandem Bikes?

A. "Yes" - Adult FATWHEELS can be mounted on a tandem bike as long as it has a standard rear frame configuration. The back portion of the frame must resemble a regular bike with a standard seat and chain stay. Please confirm this with your bike shop before ordering.

Q: Will FATWHEELS Work With A Folding Bike?

A: "No" none of the FATWHEELS products are compatible with folding bikes.


A: "Yes", the Small & Large FATWHEELS brackets have vertical slots which allow for a wide range of height adjustments. These adjustments can accommodate different tire heights and they also give users the option of raising the FATWHEELS tires off the ground as the rider gains balance.

Simply measure your bike's rear height from the ground to the center of the rear axle nut and choose the appropriate kit.

Q: Will FATWHEELS Work With A Tag-a-Long?

A: Although FATWHEELS will fit a tag-along we do not recommend it. A tag-along is designed so that the primary bike provides balance to the trailer and its' rider. The coupler supplied with the tag-along only allows rotation of the trailer coupler in two directions - either left to right or up and down. This means that both riders lean into the turns together.

If you install FATWHEELS, they will stabilize the trailer as well as the bike basically turning the two into one tandem trike. Unfortunately the combined weight of the trailer, bike and both cyclists will fatigue the FATWHEELS bracket set and possibly cause harm to the riders. One option is to have a local bike shop modify the tag-along coupler so that it rotates clockwise and counterclockwise (like some bicycle trailers do).

Therefore, it would function like a trike-trailer supporting only the weight of its' rider and the tag-along itself. Likewise, the primary bike would support its' own rider and would also lean into the turns as it normally would.

Rear Axles

Q: How long does the rear axle need to be to mount FATWHEELS?

A: Ideally, the axle should stick beyond the nuts at least 3/16 of an inch (equivalent to the thickness of three 25ยข coins) before FATWHEELS can be mounted. If your bike does not have a suitable axle length, we supply axle extenders in each kit.

Note: FATWHEELS are made to mount to 3/8" diameter axles. They may be bored out to a larger diameter (such as 10mm or 14mm) if necessary.

Q: Will FATWHEELS fit on bicycles equipped with 10 or 14mm axles?

A: " Yes", they will fit but the FATWHEELS frame mounting bracket hole of the bracket will need to be drilled out to fit. Unfortunately this will only apply to bicycles that do not require axle extenders.

Q: Can FATWHEELS be mounted on a bike with "quick-release" hubs?

A: Only the Adult FATWHEELS can. The Small and Large FATWHEELS kits require a solid rear axle with nuts for mounting. Your local bike shop can help install a solid axle if you do not have one.

Rear Suspension

Q: Will FATWHEELS work with bikes with an active rear suspension?

A: "No" this is not a good choice for FATWHEELS.

Full Suspension

Frame Configuration

Q: Can fatwheels fit bikes with a rear frame that's curved?

A: We would prefer the bike have straight seat and chain stays. FATWHEELS frame mounting brackets are designed for these types of frames.

Curved Seat Stay

Standard Seat Stay


Q: How wide are bikes equipped with FATWHEELS?

A: Small FATWHEELS - 25" wide, Large FATWHEELS - 34" wide Adult & Small HD FATWHEELS - 37" wide

Q: How much does each FATWHEELS kit weigh?

A: Small FATWHEELS - 10 lbs. Large FATWHEELS - 11 lbs. Adult & Small HD FATWHEELS 20 lbs.

Q: What size are the FATWHEELS tires?

A: ALL FATWHEELS kits use a 12.5" tire