Douglas Anderson's Road Legal Cyclecar Journal

I had a look at a few different 17" wheels which were available.

I opted for Honda Innova ANF125 front wheels and managed to pick up four of these for GBP £190 complete with tyres and disc rotors.

The ANF125 front wheels have a 1.40" x 17" rim and use 32 x 12mm bearings.

12mm spindles are not going to be man enough for single sided support on front hubs therefore I am changing the bearings to 32 x 20mm angular contact versions.

I will make my front hubs with 20mm spindles to suit.

At the rear I will use the same ANF125 front wheels but will utilise the (4) M8 disc rotor mounting holes to bolt to special fabricated drive flanges.
In addition I will add a centre bolt for extra support to the outer face of the wheel hub.

If I go for a 'road legal' Kart in the future I can fit the 220mm ANF125 front rotors to the front wheels but in the meantime I will use a pair on the rear axle only.

I was fortunate that my wheels came complete with part worn tyres, (2) were 2.50x17 and (2) were 2.75x17 so I will fit the wider types on the rear axle.

Current plan for my 'Custom' cyclekart is to build a Bugatti Type13 similar to Fabrice's.

Engine wise, I will be using a 4-speed 50cc unit (as I have one!)

Transmission will be via a jack-shaft to my dual freewheel axle.

I spent the afternoon making the eyes for my DIY front springs.

Bent some 3mm thick steel bar round 19mm turned steel bushes and welded these together.

Fitted the eyes to the leaf springs and drilled for 8mm fixing bolts through the flanges of the eyes and through the springs.

Followed by a lick of paint.

The springs were cut from an old Series 2 Land Rover multi-leaf front spring.

The overall width of the leaves was reduced to 48mm by slicing with a thin cutting disc.

It was possible to set both leaves to the same camber by cold bending in a vice.

The eyes are 670mm apart and the bow of the springs is 130mm.

I measured each spring at about 66 Lbs/in deflection, when they were at their original leaf width. I will need to re-check the figures now that I have cut the leaves down to 48mm wide.

I have now machined up the housing and built up a prototype unit.

The unit weighs in at just under 1.5Kg.

I got a 6mm keyway broach and have now cut the keyways in the hubs for the freewheels.

I have also designed the housing to mount the freewheels and the sprocket.

The 25mm axles already have full length 6mm keyways.

Thought I might try and make a dual freewheel type differential as used on some trikes/velomobiles.

The unit uses two bicycle freewheels mounted in a housing with the drive sprocket attached to this housing.

The freewheels are bolted to the housing via their original sprocket teeth.

Axle hubs are threaded into the freewheels and these hubs are keyed to the axles.

Both freewheels need to drive in the same (forward) direction therefore the right-hand threaded freewheels both need to screw to the hubs from the right-hand side (looking from the rear).
That way the hubs will always be trying to tighten under load from the drive from the housing.

I have made a start by checking that I could machine the 24 tpi threads for the freewheels.

I will be using 25mm axles with 6mm keys.
The unit will need two disc rotors.

Just finished a second unit - this time with a chain sprocket.

This 'open action' differential unit is designed for use on low powered vehicles such as cyclecars/cyclekarts.

They have 1" OD axles which can be machined for keyed flanges for keyed hubs and brake disc carriers

The complete axle is 1000mm long in total but can be shortened if required.

The unit requires additional self-aligning bearings to support the outer ends of the axles.