What is a Scarborough gearbox?

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I understand it’s a Norton gearbox with close ratio gears that retain the kickstarter but can find no information. If so, where can i get the gears from?
 
Try RGM, they offer a close ratio gear kit that will allow you to retain the kickstart shaft (using "Daytona" first gear set with 20 teeth on mainshaft and 34 on layshaft).
 
Heinz Kegler, ex Norton experimental department, called the Daytona first-gear set that would accept a kick-start a "Scarborough" first gear. I have a large pile of factory racing and gearbox literature dating from WWII onwards and I do not remember seeing the word "Scarborough" in any of it to describe gear sets.

This suggests it may have been a slang term that came into use by those involved in racing Norton and AMC machines to describe a gearbox with a wider ratio gear set for tighter and slower tracks like Scarborough itself.

The original Daytona track on the beach, with two very long straight with slow tight turns on the ends covered in sand might have been a better use for the 20/34 first gear set that accepted a kick-start which was mandatory for racing under the AMA in the USA. Later on when the Daytona race was switched to the paved Speedway the traditional Daytona gear set was too low and saw skilled racers using it locking up the rear wheel going into some turns. This of course was dangerous, and at least one top racer of the 1960's swapped a Manx first gear set into his bike after it went through tech inspection....

For someone using a four-speed box on the street who likes going around turns more than sprinting from a standing start, the Daytona first gear set would be a cheap way to improve things a little bit and still keep a kick-start. With this first gear's smaller diameter plus the hollowing out required for the kickstart ratchet, there is not a lot of material left and it looks weaker than street bike parts, but originally it was only used on 500cc bikes.

What is a Scarborough gearbox?
 
Bernhard said:
I understand it’s a Norton gearbox with close ratio gears that retain the kickstarter but can find no information. If so, where can i get the gears from?


others are telling you about the gears....what about 'Scarborough' well if you didn't know Scarborough is a seaside town in Yorkshire, England, and just outside the town this is a piece of parkland/public road used a few times a year as a race circuit...it is amazing and scary....google this....

Oliver's Mount Road Race Circuit

It is very narrow and tight, and at the end of the start finish section, which is laughingly called straight but is far from it, riders brake from well over 150 mph into a tight left and uphill hairpin called Mere....the hill is so steep that when they raced 50cc bikes there up to the '70s the riders would jump off and push up the hill....so you needed a very low gear.....

I didn't race there, but I did drive a '72 Ford Escort Mexico rally car there in an international historic rally....when we arrived there we were leading the event...but that is another story...thing is we drove the reverse direction...coming down that hill was very very hairy, but at least you can handbrake a rally car...
 
[video]http://www.youtube.com/watch?v=WxwZxXMr9eU[/video]
:D :shock: :D
 
did you see the start finish straight?....it starts before the part where jump is and goes all the way to the Mere hairpin and then up the hill....and as you may have also noted, there is an even tighter hairpin as the circuit comes down hill again!

Not for the faint hearted....
 
Yes, I do happen to know where 'Scarborough' on the east coast is -where the sea air is bracing!
I was querying about a type of gear cluster I have not heard off, but thanks for your input.
I still cannot make my mind up if this is a suitable gear setup for the road, or use the close ratio conversion on the standard Norton box that was once available from, yes that man again, Paul Dunstall in the 1960/70s.
 
In the NOC notes from 81 odd , it coverd ' closeing ' the ratios .Higher first than that , you dont get a kick start ( inside the 1st Gear ) .
C.R. Norton ( Manz ) ratios are within 1 % of C.R. Triumph Ratios , which retain the kickstart .So ' Semi Close ' is the relevant term .

Overall Gearing is as relevant , as sprocket tooth No alters overall first , effectively .Std Cam & 23 tooth you could just act normal , :mrgreen:
where the 2S required slideing / letting in the clutch holding 1200 rpms.Wet Greasy roads it would spin up the rear without due attention .

The real answer is to get Manx Ratios with a lower First,Its Called a ' FIVE SPEED ' :lol: as in a C.R box , 1sts about where ordinary second is .
( With the 4 speed is it ok getting underway in second ? ) Therefore , with a 5 speed , you get your close gears , and get youre original 1st back .

HOWEVER , unless its a crankey camey engine , the ' Semi Close ' nee ' scarborough ' ratios should be pretty good . Sometghing like dropping a tooth on layshaft drop gear , to close the rest , a few teeth out on both gears , 1st , and a tooth or is it two here or there on second.Or Find NOC Notes ! :D
 
Interesting, these gearboxes were used for the American market where the kickstarter shaft was retained;

https://www.facebook.com/media/set/?set ... =3&theater

the comment might explain it all;
"Daytona or "Scarborough" first gear set. As high a first gear ratio as could be made that would still accommodate a kick-start mechanism, mandatory for years under AMA racing rules. Ratio is about 2.3:1.....Used at Daytona from the late 1940s onwards. Heinz Kegler, ex-Norton experimental department supplied these gears to me along with the information on them. Daytona was a track with two very lon...g straights and two short tight turns. Scarborough was a track in the U.K. that had a lot of slow turns so a lower first-gear set was useful there. I have never seen any factory literature using the word "Scarborough" to describe transmission gears, so it may have been a slang term that came into use by those racing Norton's in the U.K. to describe a wider-ratio gearbox for racing Nortons."

Setup used to race at Daytona, page from tuner Heinz Kegler's notebook;

https://www.facebook.com/media/set/?set ... =3&theater
 
acotrel said:
I think all the videos I've seen on Youtube show clutch starts at Oliver's Mount. Perhaps the guys use a low first gear while keeping the higher ones close ?

I think you might have misunderstood the term "Scarborough" first gear. It’s got absolutely nothing to do with the Scarborough race circuit (Me thinks)
;
“Heinz Kegler, ex Norton experimental department, called the Daytona first-gear set that would accept a kick-start a "Scarborough" first gear.”
And; “Daytona or "Scarborough" first gear set. As high a first gear ratio as could be made that would still accommodate a kick-start mechanism, mandatory for years under AMA racing rules.”
The run and bump starts that were once the starting method of all tarmac run road races including G.Ps appear to have now disappeared into the history books :!: :shock:
 
Run and bump starts were a big part of my childhood, and I was very good at it. Clutch starts made racing older bikes more expensive - the low first gear which is necessary for a good start means the top gear is usually too low if you are using the old 4 speed close box. So now it is the 6 speed TTI box for $5000 if you want to be competitive . Clutch starts were an American invention, like never racing in the rain - part of the plastic throw-away mentality of modern society.
 
I too had problems with the clutch starts on a TZ350 Yamaha, when run and bumps were abolished, it wasn’t until I sold it that I found that you could get a lower first gear for the gearbox :!: :(
 
I haven't tried the 6 speed box yet. I wasn't smart enough to fit a pair of the various standard first gears that I've got in a box on my shelf, to the 4 speed CR box to get decent starts. It would have meant a big jump to second, however I never used to go back to first gear anywhere on our local circuit, except off the start. Heaving the bike off the start from stationary is a much bigger problem than coping with a big gap between first and second while the bike is mobile. On our circuit, the awkward gear change would have occurred on a downhill section after turn one.

I feel really stupid that the answer to the clutch starts is so simple, and it was staring me in the face. The 4 speed CR box was perfect everywhere, except off the start line. I have actually got first gear pairs out of about four different old Nortons, and they all fit ! I spoke to a friend of mine recently about this. He races a 700cc Manx - said he has three different ratio first gears for it. Dumb and Dumber ?
 
acotrel said:
Run and bump starts were a big part of my childhood, and I was very good at it.

Once when I was in my 20s I bump started a Maico motocrosser in the bottom of a ravine on a rocky creek bed, combination of miracle and the boundless ignorance and energy of youth.
 
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