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Supermono

April 2008

 

We are continuing to develop a range of transmission parts for the 4 stroke motorcross engines being converted for use in supermono racing.  Close ratio road race style 5 speed gear clusters have been produced for the CRF450 and YZF450 engines.  Higher ratio primary gears for the CRF engine are now available. 

A 6 speed gearbox for the CRF450 has successfully completed its first meeting, being placed 6th and 4th in the British Supermono Championship rounds at the Snetterton race track on 11th and 12th April. 

Five speed racing gear set

Designed to fit the standard Velocette road type gear box shells with only one small modification to part of the ratchet change mechanism.

All gears have 3 undercut engagement dogs for fast changes and positive retention.  We supply both shafts with all the gears assembled plus three selector forks, cam plate and actuating pawl, together with a layshaft bearing carrier which replaces the standard kick start boss. Alternatively, for road use,  we can supply a kick start ratcheted gear, in which cast the standard kick start boss is retained.

The gearboxes are supplied with a 19 tooth sprocket, additional sprockets are available as required.

Our ratio's are as follows:
                                                         Percentage drop

1st   21  -  27   x  D.R.   = 2.250:1
                                                       )          29%
2nd  23  -  21   x  D.R.  = 1.598:1
                                                       )          18.9%
3rd   27  -  20   x  D.R.  = 1.296:1
                                                       )          14.95%
4th   27  -  17   x  D.R.  = 1.102:1
                                                       )          9.25%
5th                                              1:1

Drive ratio 16  -  28    1.75:1

Overall reduction 1st   -   5th   55.5%

Price £1150
Additional Sprockets £45 each
Kick start alternative £50

all prices + vat & carriage

 

Six speed racing gear set

Designed to fit the standard Velocette road type gear box shells with only one small modification to part of the ratchet change mechanisms.

All gears have 3 undercut engagement dogs for fast changes and positive retention.  We supply both shafts with all the gears assembled plus three selector forks, cam plate and actuating pawl, together with a layshaft bearing carrier which replaces the standard kick start boss.

The gearboxes are supplied with a 19 tooth sprocket, additional sprockets are available.

Our ratio's are as follows:
                                                          Percentage drop
1st   21  -  27   x  D.R.  = 2.250:1
                                                       )           22.22%
2nd  24  -  24   x  D.R.  = 1.750:1
                                                      )            17.37%
3rd  23  -  19   x  D.R.  = 1.446:1
                                                      )            14.87%
4th  27  -  19   x  D.R.  = 1.231:1
                                                      )            10.5%
5th  27  -  17  x   D.R.  = 1.102:1
                                                      )            9.25%
6th                                            1:1                                   

Drive ratio  16  -  28     1.75:1

Overall reduction 55.5%

Price £1277
Additional Sprockets £45 each

all prices + vat & carriage


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Nova Racing Transmissions Ltd  8 Horseshoe Yard  Crowland  PE6 0BJ  UK
Tel: 01733 210082  Email: info@novaracing.com