Wheels & Tyres

Go-Kart Wheels & Tyres

Split

See Rule Zero

• Twin tubes, side by side, with a valve on the inside and outside of the wheel.
• Slightly easier to replace tyres/tubes in the pits as bead does not need to seal.
• Custom machined hubs.
• Part-worn tyres can be occasionally found for a reasonable price.
• Slicks are fun.

Unsplit

See Pink My Ride

• Tubeless.
• Can be difficult to replace tyres in the pits, special tools and a high flow compressor help.

Mobility Scooters

A mobility scooter frame with steering, wheels and an axle can make a solid foundation for a beginner hacky racer. Their tyres however will wear out quickly, especially on tarmac. Typically use inner tubes. Readily available spares.

Mini ATVs

See LEtsGO

Hoverboard Hub Motors

See CYBR TRK

Hoverboard wheels differ from most other types of hacky racer wheel, as the motor is built in to the centre. It is possible to fit pneumatic tyres to the 6.5" hub motors with some careful modifications.

Hoverboard Tyres

• 4.10/3.50-5 mobility scooter tyres are about the only size which can be made to fit.
• 8x3.00-5 can be abused to fit with a lot of work, but are not very practical and end up quite small.
• 8 1/2 x 2 look close, but do not fit.

Take care! There are two slightly different sizes of 6.5" hub motor around, xxxmm and xxxmm. The tyre does not fit particuarly well on xxxmm.

• Turning down the OD of the hub slightly and improving the surface finish makes fitting easier, but will weaken wheel.
• The tyres can also be made to fit by removing rubber around the inner diameter using a burr tool in a drill and taking it as close to the bead as you dare. This is easier, does not require a lathe, and does not weaken the wheel.
• Cut a notch/pocket for the valve to exit (with a hacksaw and file also works fine).
• Using washing up liquid as lube, with the tube inside the tyre and valve facing towards you, hook the bead just over the back edge of the rim.
• Work the bead around the outside of the tyre towards the front. Not too far at this stage.
• Hook the valve through the bead at the front, and push down, so it slips over the OD of the hub and into the previously cut notch/pocket.
• Work the rest of the bead and other side of the tyre around the hub.
• Reinstall the stator and cover plate.
• Inflate to ~15PSI. ~25PSI leads to catastrophic failure.

Machined notch for valve (ignore crack!)

Tyre fitted

Hoverboard Brakes

A few different sizes of bicycle brake disk can be fitted to a hoverboard motor with various adapters. CYBR TRK and Volt-Crane-O have had success using replacement 110mm Xiaomi M365 brake kits from Aliexpress.

• Drill 5mm holes on a slightly larger PCD using this scaled template File:HB_Disc_brake.pdf .
• Remove the back plate from the hoverboard motor.
• Use the template File:HB_Disc_brake.pdf to drill the same PCD in to the back plate. Use a grinder/file to make a little bit more clearance for the screw heads.
• Mount the brake disc to the back place using screws and 6x 15mm x M5 hex spacers. Screws with a small head such as button head should fit with OK clearance.
• Reassemble the motor.
• Grind a little relief in to the stub axle mount clamps if more clearance is required (see pictures).
• Mount the brake calliper (see pictures for an example).
• It may be neccesary to deflate the tyre to navigate the brake disc in to the calliper once mounted.

Typical brake listing

Brake disc mounted

Screws inside motor back plate

Brake mounted on CYBR TRK

Brake mounted on Volt-Crane-O

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