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2016 Technical Regulations

Technical Regulations 2016

Section   Description
1   Eligible Yamaha models
  Parts that must remain standard and not be modified 
regardless of model
  Parts allowed to be modified regardless of model
4   Parts allowed to be removed regardless of model
5   Model-specific regulations
  5.1 RD250/350 LC
  5.2 RD350YPVS
  5.3 RD350LC/YPVS Hybrid
  5.4 TZR250
  5.5 TDR250
6   Fuel
7   Tyres
8   Technical inspection
9   Updates/Queries

Section 1: Eligible Yamaha Models

1.1 Road-going 250 and 350 parallel twin two-strokes, model type;
1.1.1 LC Model is RD250LC 4L1 & RD350LC 4L0
1.1.2 TZR Model is 2MA and 1KT parallel twin
1.1.3 TDR Model is 3CK and 2YK
1.1.4 YPVS model is RD350LC2, RD350N, RD350N2, RD350F, RD350F2, RD350R
1.2 Only models of the same spec as the officially imported model.
1.3 Reverse cylinder or V-twin model TZRs are not acceptable.
1.4 Models with larger rim sizes or brake diameters than the official models are also illegal.

Section 2: Parts that must remain standard and not be modified regardless of model

2.1 Frame and subframe, with the exception of minor modifications permitted in the list in
sections 3.12 and 3.13
2.2 Swingarm must be from the relevant model and standard, other than the compulsory
fitting of a lower run chain guard. (LC exceptions: rules 5.1.3-5.1.4, TZR exception: rule
2.3 Cush drive and sprocket carrier
2.4 Primary drive gears
2.5 Gearbox must be from the officially imported model of the relevant motorcycle
2.6 Ignition control units must be from an officially imported model of the relevant
motorcycle. No remapping or FIII kit boxes are permitted. (LC exemption: rule 5.1.13)
2.7 No system may be fitted that will affect a dyno's ability to take a correct power reading
2.8 No redundant electrical systems are permitted
2.9 Powervalve systems, if applicable to model, must be from the relevant motorcycle and
must be fitted and fully operational
2.10 Front wheels must remain standard for the relevant model (for LC exceptions, see 5.1.1
to 5.1.6)

Section 3: Parts allowed to be modified regardless of model

3.1 Internal petrol tank filters and taps may be modified or removed but otherwise fuel
tanks must remain as standard for the model
3.2 Fuel tank cap can be modified or replaced, subject to ACU regs
3.3 Static ignition timing may be altered
3.4 Electrical components may be repositioned, and waterproofing measures taken
3.5 Rotor lightening is allowed
3.6 Barrels and head can be modified
3.7 Crankcases may only be modified to match cylinder porting and the only
permitted crank modification is the use of a full-circle crank
3.8 Sprocket cover may be modified or removed
3.9 Airbox may be modified or removed
3.10 Radiators, cooling system and thermostat may be substituted or modified
3.11 Rebores to a maximum of 2.75mm (no big bores)
3.12 Aftermarket billet clutch and non-OE pressure plate, extra plates and replacement
springs are permitted
3.13 Exhausts can be modified or replaced with alternatives. Any exhaust must conform to
the ACU noise limit of 105db
3.14 Minor frame and subframe mods are allowed for cosmetic reasons, bodywork fitment
and steering damper mods, but not to change geometry, lightening or bracing
3.15 Ancillary frame brackets can be removed, typically unused mounting lugs, additional
lugs may be added to assist the fitment of bodywork
3.16 Chassis and wheel bearings may be upgraded to superior specification, but must be to
standard diameter
3.17 Fork internals and caps may be modified or replaced with cartridge kits of higher specification.
3.18 Rear shock may be re-gassed, spring may be replaced to suit riders requirements. Alternatively, any commercially available shock absorber may be used. This must be of single unit construction. No remote reservoirs, piggy back reservoirs or remote pre load units will be allowed. The unit must also be a direct fit to the existing mounts without modification to the frame or linkage.
3.19 Rear suspension tie-bars may be modified or replaced to modify the ride height
3.20 A steering damper is allowed
3.21 Handlebars can be modified, replaced and remounted with due consideration paid to
clearance of fairings and bodywork
3.22 Race bodywork can be fitted, but must not alter original silhouette at front of bike. Seat
unit may be replaced with any suitable unit
3.23 Mudguards
3.24 Double bubble and tinted screens are allowed
3.25 Wheel spindles, subject to use of original material and thickness. They must be at least
standard length and may be lengthened to allow use of R-hook
3.26 Rear brake fluid reservoir. The ‘HRC’ tube modification is allowed
3.27 Any mass production fixed ratio master cylinder for front and rear braking system may be used. This does not mean race production Brembo, AP Lockheed or bespoke units.

Section 4: Parts allowed to be removed regardless of model

4.1 Equipment for road use like mirrors, horn, indicators, pillion pegs and ancillary brackets
originally to support road-going parts
4.2 Top chainguard (a bottom run 'sharks fin' toe guard must be added as per ACU
4.3 Mudguards
4.4 Speedo, cable and speedo drive. The speedo drive can be substituted for a suitable
4.5 Charging system, including regulator-rectifier and battery
4.6 Oil tank and pump
4.7 Airbox
4.8 Kickstart mechanism
4.9 Gearbox sprocket cover
4.10 Thermostat
4.11 Rear brake fluid reservoir

Section 5: Model-specific regulations

Section 5.1: RD250/350 LC non-powervalve 4L0 and 4L1
5.1.1 250LC is allowed twin discs and callipers from the 350LC
5.1.2 YPVS forks, wheels and brakes can be fitted
5.1.3 Swingarm bracing and period aftermarket swingarms are allowed
5.1.4 Any class-legal YPVS bodywork/frame/swingarm part can be fitted, with the exception
of full fairings )
5.1.5 TZR forks, wheels and brake may be fitted, along with the rear wheel, as long as the
braking system conforms to TZR regulations. 'Blue spot' caliper may be fitted to LCs
ONLY if they are fitted with TZR equipment along these lines. See TZR rules for full
definition of this caliper.
5.1.6 Any shock can be used
5.1.7 The 'Pro-Am' Fairing and belly pan are permitted
5.1.8 Non-standard or modified carburettors are allowed
5.1.9 YPVS conrods can be used
5.1.10 Any ignition is allowed 

Section 5.2: RD350YPVS LC2, F1/N1, F2/N2, RD350R - 31K, 1UA
5.2.1 Any OEM Yamaha twin opposing piston calliper, with an 83mm bolt pitch, that will fit
without additional mounting brackets is allowed
5.2.2 Allowance of four piston brake callipers with 83mm bolt spacing from the following
models, to fit 350YPVS 31K or F2 forks, without any adapter plates.
Callipers must be from the following eligible models only. Master cylinder must
remain 5/8” i.e. 16mm: FZR400 3TJ, TZR250 3MA, TZR250 3XV, R1-Z 250, Triumph
TT600 and 595 series
5.2.3 Ignition systems can be a combination of eligible models or an aftermarket non programmable YPVS replacement
5.2.4 Non-standard or modified carburettors are allowed
5.2.5 TZR forks, wheels and brake may be fitted, along with the rear wheel, as long as the braking system conforms to TZR regulations. The YPVS rear swing arm must remain. 'Blue spot' caliper may be fitted to YPVS ONLY if they are fitted with TZR equipment along these lines. See TZR rules for full definition of this caliper

Section 5.3: RD350LC/YPVS Hybrid
Rules as RD250/350LC (section 4.2) with the following exception
5.3.1 Ignition must be OEM Yamaha as per YPVS rules and the Powervalve system must be

Section 5.4: TZR250 1KT, 2MA
5.4.1 Model 2XW-1 swinging arm, shock and linkages are permitted as these were
officially fitted to later model 2MAs imported to the UK.
5.4.2 Rear wheel can be replaced with a suitable 3.5in Yamaha wheel that will accept the
standard spindle, cush drive and sprocket carrier
5.4.3 We allow use of any OEM Yamaha monobloc construction front calliper with 100mm
bolt pitch that attaches directly to the fork leg without the need for an adaptor
5.4.4 Carb needles and jets may be replaced. Carb bodies must be standard
5.4.5 Standard 2.15in diameter front wheel can be used
5.4.6 TZR/TDR wheel change eligibility – valid from 2013 onwards
Below is a list of wheels that make up eligible options for front wheel variant for the
TZR250 and TDR250 and also for the LC Hybrid running the TZR wheels
This list may change in the future as we find additional wheels that are suitable
Note the conditions are:
- The original specification wheel spindle must be used
- No adjustments to the forks or caliper can be undertaken to allow fitment
- Standard wheel must be able to fit straight back into to setup using standard size spacers,
spindle and eligible caliper setup
- The wheel must be off a Production Yamaha motorcycle
Wheel ID Number Size
TZR125R Brembo 2.75 x 17
TZR250 (2XT) F-44 2.75 x 17
R1-Z 250 (3XC) F-44 2.75 x 17
FZR250 (3LN model) F-44 2.75 x 17
FZX250 F-44 2.75 x 17
TZR125RR** F-49 3.00 x 17Page | 7
TZR250 (3ma & 3xv) ** F-49 3.00 x 17
FZR600 (3HE) 3.00 x 17
SZR660 ** Y-2 F-49 3.00 x 17
** A modification to remove 4mm from the wheel is required

Section 5.5: TDR250 3CK, 2YK
Rules as TZR250 (section 4.4) with the following exceptions
5.5.1 Footrest position may be altered by modifying or removing frame lugs, allowing
fitment of aftermarket rearsets
5.5.2 CDI and PV boxes from eligible TZR models are allowed

Section 6: Fuel

6.1 Pump fuel only. Max 99RON, premixed with two-stroke oil if necessary. No octane
boosters or other additives allowed

Section 7: Tyres

7.1 Tyres: Any moulded treaded tyre. Wets are allowed. No slicks

Section 8: Technical inspection

8.1 Technical Inspection.
Random technical inspections may be carried out by ypmrc technical coordinators with, if necessary, supervision of BMCRC chief technical officer.
Any official protest must be carried out in accordance with BMCRC /ACU protest procedure

8.2 Any changes made to the regulations will be decided under the control of the club
coordinators and in some cases BMCRC Tech officials

Section 9: Updates/queries

9.1 Any changes made to the regulations will be decided under the control of the club coordinators and in some cases BMCRC Tech officials
9.2 For any information concerning updates to or questions about the regulations, contact: Len Whalin – This email address is being protected from spambots. You need JavaScript enabled to view it.