G: Gearbox (Twin) Gearing - Series ‘C’ Black Shadow

Kiwi_Tim

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Fairly new to vincents and mine has stock wheels and sprockets: At what sort of speed would it could be expected to have the clutch fully released in first gear ? Likewise at what sort of speed would 4th become natural to motor in rather than 3rd
I suspect I have a tall 1st gear option.
 

Albervin

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Tall or intermediate first gear in Shadows ended about engine 2500. Many were replaced with standard because they are a PITA around town. If you have a standard front and rear sprocket you will need to feed a few revs in and then keep feeding them in until the clutch is fully home. How fast? Really depends on the lay of the land but probably at least 15mph. I too have high first gear and fitted a 48T rear sprocket to make life a bit easier. I usually do not select top gear (on the flat) until about 55mph but sometimes closer to 70 mph. The engines like to rev rather than lugged; about 3,500 rpm is a nice relaxed cruise.
 

Kiwi_Tim

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Mines a late one (Dec 53), and I need around 30mph to be comfortably off the clutch, any slower and the clutch needs to be feathered. I'm finding 50-70mph its happy in 3rd and top needs to be at the top of that range and top feels like an overdrive
 

Albervin

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Check the size of your sprockets. The rear is easy the front is not. Unusual for such a late Shadow to have an intermediate first gear unless it was retro fitted.
 

Bill Thomas

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Top is an overdrive, But not that much !, I have never looked at the speedo in first, But yours sounds wrong.
My Ex L/ning will come down to 40 mph in top on the flat.
I think you have a problem with the Carb's or ign', Maybe the ATD is not working right ?.
After all these years, Your gearing could be anything ?, I have one Twin with a high first gear, And one not,
Can't say it makes that much difference, Unless you, Have someone on the back ?, Or lots of stuff ?.
Can you give us what Spec' your Bike is ?, Carb's ign' etc. Cheers Bill.
 

Bill Thomas

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Tim, Any chance you could have a ride on another Twin ?, Just to see. Cheers Bill.
A very early memory of mine, Was my Brothers friend, Smithy, Bringing me home from Work, I was about 15 years old, On his Blue "D" Twin, He overtook a Car on a slow bend, Wrong side of the road, About 35 40 mph, And changed into TOP !!, I was always Big.
 
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Albervin

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Pulling away from Marcus's place with high first gearing was almost like riding a two stroke. On the road though it is just fine. It would be an utter bastard in a hilly town with stop signs and traffic lights though. Agree that the ATD should be checked as it could be sticking or just lazy. You do say it has STOCK sprockets Tim. Are you sure?
 

greg brillus

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Standard twin Front gearbox output 21 teeth rear wheel 46 teeth. No overdrive in top gear, one in one out.
 
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