CHAPTER TWENTYFIVE
25
ROAD RACING - POST CLASSIC
25.1
Introduction:
There shall be three groups of Post Class road racing machines:
(A) Pre 72 which shall consist of machines manufactured after January 1st
1963 and before October 30th 1972.
(B) Pre 82 which will consist of racing machines manufactured after the
closing date of the Period 1972 class and before December 31st 1982.
(C) Pre 89 which will consist of racing machines manufactured after the
closing date of the period 1982 class and before December 31st 1989.
(a)
These rules are intended to ensure a high standard of
authenticity and presentation of the representative periods.
(b)
All machines must comply with the safety and technical
requirements as detailed under chapters 8 & 10 of the MNZ
manual.
(c)
Later versions of the same models released (but not updated)
eg Honda 750 K1-K6 may be acceptable as eligible for Pre 72
when competing in a racing class.
(d)
Pre 72 cut off date is to exclude the following motorcycles;
Kawasaki Z1 900, Yamaha TZ and RD from this class.
(e)
Pre 82 specifically excludes the following: Honda VF750F
interceptor, Yamaha RZ (all models) Suzuki GSX 1135, GSXR all
models GPZ 900 all models Yamaha FJ 1100, Ducati F1 all
models Suzuki RG 250, 400, 500 Gamma road bikes.
25.2
Eligibility and general requirements
25.2.1
Eligibility
The eligibility and dating of post classic motorcycles shall be considered in
terms of the major components. The group into which a post classic machine
is classed will be determined by the age of the newest component.
25.2.2
Major Components
Major components are: Frame (including Swingarm), Engine and Gearbox
castings, carburetors, Brakes (excluding front and rear master cylinders which
are open) and forks. These are to be manufactured between Jan 1st 1963 and
December 31st 1989. Major components manufactured in any country shall
be acceptable. The onus of proof of eligibility shall rest wholly upon the rider
or entrant of the machine.
Modifications to major components are allowed, providing that such
modifications are visually indistinguishable from modifications proven to have
been used during this period. The onus of proof rests with the entrant or rider
of the machine.
©Motorcycling New Zealand Incorporated 2013
The copyright in this document is owned by Motorcycling New Zealand Incorporated (MNZ) and it
may not be reproduced or altered, either in whole or in part, without the prior written permission of
MNZ.
25.2.3
Replica Parts and Materials
Replica parts, major or otherwise, may be used in any proportion, provided
that they are true and faithful copies of the original components made to
original dimensions from the materials originally specified. In the event of
originally specified materials being unobtainable, then materials used must be
near to those originally specified.
Carbon Fibre and Kevlar components, major or not, are prohibited in pre 72
and pre 82. APE and MTC and similar big block after-market engine blocks are
prohibited.
Carbon Fibre, Kevlar and composite materials shall be permitted in Pre 89.
Accurate replicas of period equipment that is still manufactured are permitted.
Remember that the onus of proof for a period part is on the rider. Any doubt
may result in a protest regarding eligibility.
25.2.4
Fuel Induction
Please see individual classes for fuel induction details.
25.2.5
Ignition Systems
Electronic ignition systems shall be permitted.
25.2.6
Fairing
Fairing and streamlining is permitted if they are of the type and style in
keeping with the period of competition.
25.2.7
Modifications
Any modifications made to racing machines must be of the type and style in
keeping with the period portrayed in these rules.
25.3
Pre 72 Class Specifications
25.3.1
Suspension & Brakes
Air assisted front forks, mono shock rear suspension, and rear disk brakes,
unless fitted as original equipment are prohibited. Front disks must be period,
and are limited to 300mm maximum diameter with a maximum of 2-pistons
per calliper unless fitted as original equipment to the bike in question.
25.3.2
Wheel Design
Wheel design must be of the wire spoke type. Wheel rims, unless fitted as
original equipment, shall be 18” minimum diameter, maximum width of 2.5”.
25.3.3
Tyres
Slick, or grooved slick tyres are prohibited.
25.3.4
Shocks
Shock absorbers with remote or external reservoirs are prohibited.
©Motorcycling New Zealand Incorporated 2013
The copyright in this document is owned by Motorcycling New Zealand Incorporated (MNZ) and it
may not be reproduced or altered, either in whole or in part, without the prior written permission of
MNZ.
25.3.5
Fuel
Fuel: Open, refer to Rule 10.17.3
25.3.6
Fuel Induction
Fuel induction must be by way of period style carburetor of slide or diaphragm
type.
All carburetors are to be of square or round slide type, except for Gardner flat
slide carburetors. All flat side carburetors are otherwise banned. (Onus of
proof is on competitor rider or entrant of the machine).
Turbo and supercharging shall not be allowed.
25.4
Pre 82 Class Specifications
25.4.1
Exceptions
Water cooled engines and mono shock rear suspensions, unless fitted as
original equipment, are prohibited.
25.4.2
Wheels
Wheel designs shall be of the wire spoke or alloy construction. Wheel rims,
unless fitted as original equipment, shall be 17” minimum diameter. Maximum
width shall be 3.5” front and 5.00” rear.
25.4.3
Tyres
Tyres, open
25.4.4
Forks
Upside down forks are prohibited. Forks must be period items. Internal spring
and valving modifications are permitted.
25.4.5
Fuel
4 Strokes ~ open refer to rule 10.17.3
2 Strokes ~ petrol only refer to rule 10.17.1
25.4.6
Brakes
Front and rear brakes must be manufactured in the period, or faithful replicas.
Floating disk carriers are banned unless fitted as original equipment to the bike
concerned. Maximum disk diameter is 300mm and maximum number of
pistons per caliper is 2, unless fitted as original equipment to the bike
concerned (Onus of proof is on rider or entrant of the machine).
Exceptions: Rear disc is open, but most not exceed 300mm diameter. Wave
discs are banned. Master cylinders (front and rear) are open, but no direct pull
or “radial” front master cylinders.
25.4.7
Fuel Induction
©Motorcycling New Zealand Incorporated 2013
The copyright in this document is owned by Motorcycling New Zealand Incorporated (MNZ) and it
may not be reproduced or altered, either in whole or in part, without the prior written permission of
MNZ.
Fuel induction must be by way of period style carburetor of slide or diaphragm
except where fuel injection was fitted as standard (eg GPz 1100 Kawasaki).
Except for period style EI, Lectron and Gardner Flat Slide carburetors, all
carburetors are to be of square or round slide type only. All other flat side
carburetors are specifically banned, unless fitted to the specific bike during the
period. (Onus of proof is on competitor rider or entrant of the machine).
Turbo and supercharging shall not be allowed unless where fitted equipment
(eg Honda CX500, Yamaha XI650 Turbo or Kawasaki ZIR Turbocharged).
Where fitted as original equipment to the motorcycle in question,
turbocharger or supercharger unit, waste gate and intake manifold only as per
manufacturers original specifications.
25.5
Pre 89 Class Specifications
25.5.1
Exceptions
Carbon Fibre and composite wheels are specifically prohibited, unless used on
the specific bike in the period. (Onus of proof is on competitor rider or entrant
of the machine).
Carbon Fibre frames and swing-arms are specifically prohibited unless used on
the specific bike in the period (eg: Plastic Fantastic). Onus of proof is on
competitor rider or entrant of the machine.
25.5.2
Wheels
Front wheel shall have a maximum width of 3.5” and minimum diameter of
16”.
Rear wheel shall have a maximum width of 5.5” and minimum diameter of 16”.
Wheels can be cast or spoke type.
Magnesium wheels are permitted. Carbon fibre wheels are banned.
25.5.3
Tyres
Open
25.5.4
Forks
Upside down forks are prohibited unless originally fitted to the bike model in
the period. Forks must be period items. Internal spring and valving
modifications are permitted.
White Power and Ohlins had very limited supplies of USD forks available to
special teams on their works or works issue motorcycles. These specific forks
may be used if originally fitted to the bike in question (eg 888 Corsa
Superbike). The onus of proof is on the rider.
25.5.5
Fuel
4 Strokes ~ Open refer to rule 10.17.3
2 Strokes ~ Open refer to rule 10.17.1
25.5.6
Brakes
©Motorcycling New Zealand Incorporated 2013
The copyright in this document is owned by Motorcycling New Zealand Incorporated (MNZ) and it
may not be reproduced or altered, either in whole or in part, without the prior written permission of
MNZ.
Front and rear brakes must be manufactured in the period, or faithful replicas.
Maximum disk diameter is 320mm and maximum number of pistons per
caliper is 4, unless fitted as original equipment to the bike concerned (Onus of
proof is on rider or entrant of the machine).
6 pot calipers are banned unless fitted to machine as original equipment.
Rear disc is open, but must not exceed 300mm diameter.
Wave discs are banned. Carbon discs are banned.
Front and rear master cylinders are open, but no direct pull or “radial” front
master cylinders.
25.5.7
Fuel Induction
Fuel induction must be by way of period style carburetor of slide diaphragm,
except where fuel injection was fitted as standard (eg GPz1100 Kawasaki).
Flat side carburetors are permitted, but must be period or replica period items.
(Onus of proof is on competitor rider or entrant of the machine).
Turbo and supercharging shall not be allowed unless where original fitted
equipment (eg Honda CX500, Yamaha XI650 Turbo or Kawasaki ZIR
Turbocharged). Where fitted as original equipment to the motorcycle in
question, turbocharger or supercharger unit, waste gate and intake manifold
only as per manufacturers original specifications.
25.6
Junior Road Racing – Post Classics (pre 72, Pre 82 and Pre 89)
Post Class Classes acceptable for Junior road racing are:
Up to 250cc 4 Stroke
Up to 125cc 2 Stroke
All junior competitors in Road Race events are to wear a high visibility vets
over their leathers for the first 10 events at which they compete. Proof of
these events will be from entries in their log book.
25.7
Post Classic Classes
Class
Ultra
lightweight
Lightweight
Pre 82
0-125cc 2 & 4 Stroke
Junior
251 – 430cc 2,3,4 cyl 2
Stroke
Up to 600cc 4 Stroke
431-1300cc 2+ cyl 2
Stroke.
601-1300cc
single
cylinder 2 Stroke
601-1300cc 4 Stroke
Senior
126-250cc 2 & 4 Stroke
Pre 72
0-125cc 2 & 4
Stroke
126-250cc 2 & 4
Stroke
251-500cc 2 & 4
Stroke
501 -1300cc 2 & 4
Stroke
©Motorcycling New Zealand Incorporated 2013
The copyright in this document is owned by Motorcycling New Zealand Incorporated (MNZ) and it
may not be reproduced or altered, either in whole or in part, without the prior written permission of
MNZ.
Formula One
Formula Two
Grand Prix
250 2 Stroke
Formula
Three
Pre 89
431cc-1300cc multi cylinder 2
Stroke
601cc-1300cc single cylinder 2
stroke
601cc-1300cc multi cylinder 4
stroke
231cc-430cc multi cylinder 2
stroke
401cc-600cc 4 cylinder 4 stroke
Up to 7450cc, 2 valve per cylinder
air cooled twins
125cc-400cc multi cylinder 4
stroke
Unlimited single cylinder 4 stroke
Up to 600cc single cylinder 2
stroke
Up to 250cc production based 2
stroke
Up to 500cc twin cylinder 4 stroke
©Motorcycling New Zealand Incorporated 2013
The copyright in this document is owned by Motorcycling New Zealand Incorporated (MNZ) and it
may not be reproduced or altered, either in whole or in part, without the prior written permission of
MNZ.