Norton Gearbox Fitted to Comet

[highbury731]

RGM do a lot of Norton stuff including a couple of close ratio adaptations but it is a bit of a jungle

RGM offer their own special close ratio cluster for the Norton / AMC box. According to my calculations, this uses the Manx sleeve pair, any post-1960 third, Commando second, and Daytona first. It's a careful selection of existing Norton gears. You can pick and choose - and you don't have to buy the full set.

Daytona first gear? When Norton sent a special Manx racer to Daytona circa 1949, they had to fit a kick starter, with the highest possible first gear. 15:27 is the closest first possible with the kick starter, It was a very rare gear. I think it
may have been offered in the Norvil period.

Two provisos:
- It gives a lower-geared kick starter.
- make certain whether it's made for the AMC box or vertical, due to the shoulder on the side of the first mainshaft gear. If the supplier doesn't have the version you want, it's not a deal killer. The shoulder can be ground off for fitting to the earlier box, and a spacer can be made to fit an earlier type gear into an AMC.

 

[BigEd]

Daytona first gear? When Norton sent a special Manx racer to Daytona circa 1949, they had to fit a kick starter, with the highest possible first gear. 15:27 is the closest first possible with the kick starter, It was a very rare gear. I think it
may have been offered in the Norvil period.

I bought a second hand B.S.A. Goldstar in 1965. The Clubman models usually had the RRT2 gearbox with very close ratios. The ratios in mine were close with a first gear lower than the RRT2 but higher than the STD box. The box was stamped DAY and I assumed that maybe it had a Daytona connection. The lower 1st gear certainly gave the clutch an easier time in town traffic.

 

[Dinny]

My Norton Inter has a close ratio box and I've been advised by the Norton expert that to make it more manageable on the road (when it's finished) a Daytona first gear is the way to go.
I'll try it with the std close ratio box first and I will probably end up fitting a Daytona first gear in the future, I'll see how it goes first...

 

[Black Flash]

it is good to hear now how it is properly done now.
when I started my black flash project years ago the people I asked could not tell me the fitting method out of their heads, so I chopped the lugs off the Commando box, machined new ones to copy the Burman sliding arrangement at the bottom and made a jig to have them rewelded.
years later I saw how easy it was to make without the need to alter the box's lugs. That the good thing about internet.

Bernd