Photo Help Photo 0190 - Do You Recognise Someone or Something?
Richardson is correct, but the Vincent racers all used 520 chains (Black Lightnings and Grey Flashes) and a 44T sprocket will fit on a brake drum without the chain hitting the drum. David Tompkins has a 44T sprocket for his racer to use at Daytona. I don't know what chain was used with the Edgar Black Shadow, but Rollie's Black Lightning would have used a 520 chain.
It makes sense to have a large selection of rear sprockets and the adaptor can be made as strong and as light as necessary, whereas the brake drum is what it is.
I believe that the tallest sprocket Alp used was a 29T rear sprocket on his Rapide, but I think his record came with a few more teeth.
David
Rollie Free was a true master of speed!!
Add to the calculation when running on Bonneville Salt Flats:
A more or less slippery salt surface, wind resistance, air density, jetting, and more.
FYI..I went the same speed (>145 mph) with 22/43 and 22/41 gearings on the same day.
Add to the calculation when running on Bonneville Salt Flats:
A more or less slippery salt surface, wind resistance, air density, jetting, and more.
FYI..I went the same speed (>145 mph) with 22/43 and 22/41 gearings on the same day.
Last edited:
Sounds to me like it was over geared ?,
I averaged 141.9 mph over a flying kilo in UK On my Road Bike Special,
22 gearbox and 48 rear, = Near standard gearing ?,
I shot back to the paddock and put a 46 rear on, But I could only then Average 136 mph.
We had 100 octane petrol in them days at the road side pumps.
I'm with you Bill........everyone thinks that with a big engine it will keep pulling forever. Simply not the case, you will bog it down. It actually takes a certain amount of power to achieve so much speed........better off letting the engine pull more revs, this will give you much better drive out of a corner........If you were to over rev it down a straight, it's most likely only for a couple of seconds which should do no harm to a well built engine. My single racer is still a bit over geared for the track we use here.......because it is so torquey, it seems unnecessary to rev it to the redline 7000 (7200) on the limiter.......It does it no problem on the dyno........But on the track I shift way before that........Its a work in progress.......Cheers.
On that day mine went way over 6000 rev's, But never bothered to work it out,
Not clever enough !,
Just thought one tooth bigger on the gearbox = two on the rear + or - a nats ?.
Being a dreamer I went for 150 with 22 x 46, But as you say it made it slower,
I was cheating a bit with a cut down MV Augusta 3/4 Fairing.
Funny how a lot of tweaked Vincent twins do just over 140,
Even the Terry Prince 1100cc I saw did 141 a long time ago ?.
Not clever enough !,
Just thought one tooth bigger on the gearbox = two on the rear + or - a nats ?.
Being a dreamer I went for 150 with 22 x 46, But as you say it made it slower,
I was cheating a bit with a cut down MV Augusta 3/4 Fairing.
Funny how a lot of tweaked Vincent twins do just over 140,
Even the Terry Prince 1100cc I saw did 141 a long time ago ?.
Attachments
There is no way Rolly Free would have gone over 150 in 1948 if he'd been sitting normally on that bike........Most bikes need a good 90 HP to do 150 MPH whilst sitting normally and with riding gear on..........i figure most "Hotted up twins" from back in the day (or even now for that matter) would be putting out no more than 80 hp at best, this at the stock 1000 cc engine size.
TouringGodet
Well Known and Active Forum User
VOC Member
VOC Forum Administrator
VOC Forum Moderator
Yes, Denis Minett actually records that the last test runs were made at Gransden, on 29 July, 1950. Petrol consumption measured as 8 MPG. A total of 158 miles were covered.
Makes one wonder then Greg how Russell and Bob did the 185 and 178 in Christchurch.