All of the details are based upon information that has been posted on the UK Karting Notice board, or
from individuals. There are no hard and fast rules but, for someone starting out, these figures are a
reasonable starting point. They are based upon dry conditions. Remember that you will have to alter
the gearing for a wet setup.

It is recommended that if you are in doubt about the choice of sprocket, go and talk to some of the
other people who are testing/racing. Most will be extremely willing to help.
Remember: There is no substitute for testing.

It is well worth remembering that sprockets and curbs do NOT mix and the use of a sprocket guard
is highly recommended. This is not just to save the sprocket, but to help prevent getting a twisted
crankshaft and the loss of many pounds from the bank account.
Entries shown with / are engine/axle sprocket sizes. Entries with - are axle sprocket range.

If you can fill in any of the blanks, or know better, then please e-mail Rob Cannell
Also, if you can provide details for Prokarts ; World Formula etc. , plus other circuits then
they will be incorporated.
If you want details of equivalent gear ratios, to those specified on this page, then Click here ....
.
CADETS
ROTAX
TKM 2/
GEARBOX
BILAND
Circuit
Comer
W60
Honda
WTP
Mini
Max
Jnr
Snr
Snr
Hvy
Jnr
Ext
Jnr
125
Nat
250
Nat
Jnr
Snr
20T
(10T engine sprocket)
15T
11T
Bayford Meadows
...
72
...
12/85
12/83
12/85
...
88-89
88
...
...
...
79
71
Blackbushe (Camberley)
93-95
...
95-97
...
...
12/86
...
85-86
85-87
...
...
...
...
...
Boyndie
...
...
...
13/75
13/80
12/79
...
87
85
...
...
...
...
...
Buckmore
92
...
92-94
12/79
12/84
11/79
...
84-87
89
...
...
...
76
70
Clay Pigeon
86
...
88-90
13/71
12/70
12/75
...
77-78
79
...
...
...
77
71
Crail
...
...
...
...
...
12/79
...
80
81
...
...
...
...
...
Dunkeswell
...
73
...
...
...
12/80
12/83
81
77
...
...
19/27
77
71
Ellough (Beccles)
...
...
96
...
12/83
12/89
...
86
86
...
...
...
...
...
Forest Edge
...
69-72
89-91
12/74
12/75
12/77
12/82
78-80
81
...
...
...
...
...
Fulbeck (this site)
91
73
91-93
13/79
12/80
12/81
...
85-86
81-83
...
...
19/27
...
...
Genk
84
...
...
...
13/77
...
...
...
...
...
...
...
...
...
Glan Y Gors
86
73
87-88
13/73
13/74
12/77
...
76
75
...
...
...
79
72
Golspie
...
...
...
...
...
12/72
...
78
...
...
...
...
...
...
Hooton Park
88
76
...
13/76
13/79
12/78
...
82
80
...
...
...
...
...
Hullavington
...
...
...
...
...
...
...
...
...
...
...
...
...
...
Kimbolton
88
...
89
13/74
12/73
12/78
...
81
78-79
...
...
18/26
76
68
Larkhall
...
70-72
...
13/80
12/74
12/83
...
81-85
87
...
...
...
77
71
Llandow
95-97
...
95-99
...
12/79
12/84
...
87
90
...
...
...
77
70
Lydd
...
72
...
13/73
12/74
12/76
12/79-80
82
80
...
...
...
76
70
Milton Keynes
...
...
...
...
12/89
12/89
...
...
...
...
...
...
...
...
Nutts Corner
...
...
...
...
...
...
...
87
85
...
...
...
...
...
Pembrey
...
...
...
...
...
...
...
86
85
...
...
...
...
...
PF International
88
...
87-93°
13/75
12/75
12/79
12/80
83
79-80
...
...
...
...
...
Red Lodge
97
...
...
...
...
12/87
12/89
90
88
...
...
...
...
...
Rednal
...
...
...
...
...
12/80
...
...
... 
...
...
...
78
69
Rissington
86-87
...
93-95
13/74
12/73
12/78
12/80
82
82
...
18/86
19/27
81
74
Rowrah
93
76
93-95
12/78
12/82
12/87
...
88
86
...
...
...
...
...
Rye House
93
82
95-96
12/80
12/82
12/86
12/87
87
86
...
...
...
79
72
Shenington
86
...
90-92
13/75
12/74
12/76
...
82
80
...
...
19/27
75
67
Stretton
...
...
...
...
...
...
...
84
...
...
...
...
...
...
Tattershall
...
...
...
13/77
...
12/81
...
...
...
...
...
...
...
...
Tilbury
...
...
...
...
...
12/89
...
88
87
...
...
...
...
...
Tockwith
...
...
...
...
...
12/86
...
...
...
...
...
...
...
...
Warden Law
91-94
...
...
...
13/79
12/85
...
88
87
...
...
...
76
70
Whilton Mill
88
73
90-92
13/76
12/75
12/79
12/82
85
81
...
...
...
77
71
Wigan
81
75
82-84
14/71
14/74
14/79
...
72
69-70
...
...
...
...
...
Wombwell
89†
69-70
88-90
13/77
12/74
12/80
...
83-84
80-81
...
...
...
...
...
Woodthorpe
...
...
...
...
...
12/81
...
...
...
...
...
...
...
...
°All depends on grip, weird circuit.
†This is with Tillotson carb. Take 5 teeth off for Tryton (allegedly).		      
Thanks to Saxon Motorsport
for the BILAND details