Amal carbs setup for SFC?

As far as I am aware, the parts to build a light SFC crank have become very rare.
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True - but a light and strong crank (even lighter than a late SFC one) can be made from two triple inner webs and turned down SF outers - using a custom made centre pin. - Regards - Phil
 
If Julian can do what he's doing building his race bike (or Red with his clutch/outrigger gearbox shafts and the rest), anything is possible re making SFC parts from scratch.
 
GregT said:
Given enough of a market, it's worth tooling up for remanufacture. Is the market there ?
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The top few percent have all the money. I think that Red does lightened SF cranks for lots of his 270 conversions, which would of course work with 360 cranks. Unless you are racing very hard you don't really need an SFC centre section. But if someone wants a "true" SFC copy, and the sky is the limit, then even making new gearbox shafts is within range, as well as making replica electronica frames. after all it is just fabricated metal. If they have that sort of money they would just buy the real thing, Paul's will be on the market soon unless he can get the highway pegs and ape hangers to fit. For 1200TS question about how can you "expose" a copy, I would say that in many cases you couldn't without stripping the motor.
 
Tippie said:
The top few percent have all the money. I think that Red does lightened SF cranks for lots of his 270 conversions, which would of course work with 360 cranks. Unless you are racing very hard you don't really need an SFC centre section. But if someone wants a "true" SFC copy, and the sky is the limit, then even making new gearbox shafts is within range, as well as making replica electronica frames. after all it is just fabricated metal. If they have that sort of money they would just buy the real thing, Paul's will be on the market soon unless he can get the highway pegs and ape hangers to fit. For 1200TS question about how can you "expose" a copy, I would say that in many cases you couldn't without stripping the motor.
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I bought mine with a broken valve springs, so top end was off. I knew what the crank and rods looked like.
Many little details will indicate what you're looking at.
Many bikes are documented so a purchaser needs to ask.

Quite a few years back, a friend asked me to come and have a look at an SFC for sale in an auction house, just over the border in Belgium. We went and from the other side of the room, you could see that it was an orange 750 Cafe racer. I had to convince the auction house that it wasn't an SFC though. The GT stamping on the lower left engine mount was decisive. The machine was taken out of the sale.
There's a French market Jota, aka 3CL complete with flat pistons and A12 cams but Jota cans, presently for sale in the States at around $23 000. Somebody is going to get done.

I'm having a crank re manufactured for my 8 cylinder Bugatti. I found a machine shop locally.

Paul
 
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Tippie said:
The top few percent have all the money. I think that Red does lightened SF cranks for lots of his 270 conversions, which would of course work with 360 cranks. Unless you are racing very hard you don't really need an SFC centre section. But if someone wants a "true" SFC copy, and the sky is the limit, then even making new gearbox shafts is within range, as well as making replica electronica frames. after all it is just fabricated metal. If they have that sort of money they would just buy the real thing, Paul's will be on the market soon unless he can get the highway pegs and ape hangers to fit. For 1200TS question about how can you "expose" a copy, I would say that in many cases you couldn't without stripping the motor.
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It would be interesting to have a look and see how expensive the gear box shafts are really to make, If there was interest I would get a price for them
 
From what I understand is that the gearbox difference raises 1st and 2nd gears so get rid of the big jump down from third which is a bastard in chicane type corners when racing my SF2, but there is no way I would want a taller 1st gear as I punish the clutch like hell getting off the line with the 19/40 std gearing I race with (I ran 42 tooth rear for ten years). Other than that it uses needle rollers in place of bushes? Red´s outrigger would have been a worthwhile mod from the factory. How many people actually "race" SFCs these days? Not many of us could even live with the ergonomics for more than a very short ride.
On my SF2 for long rides (1600km+ days) I used to have my sleeping bag and other soft stuff packed into my tank bag and I rested my chest on it, took all the weight off my hands, but that wouldn't solve Paul's cricked neck problem.
 
Tippie said:
From what I understand is that the gearbox difference raises 1st and 2nd gears so get rid of the big jump down from third which is a bastard in chicane type corners when racing my SF2, but there is no way I would want a taller 1st gear as I punish the clutch like hell getting off the line with the 19/40 std gearing I race with (I ran 42 tooth rear for ten years). Other than that it uses needle rollers in place of bushes? Red´s outrigger would have been a worthwhile mod from the factory. How many people actually "race" SFCs these days? Not many of us could even live with the ergonomics for more than a very short ride.
On my SF2 for long rides (1600km+ days) I used to have my sleeping bag and other soft stuff packed into my tank bag and I rested my chest on it, took all the weight off my hands, but that wouldn't solve Paul's cricked neck problem.
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There are 2 types of commercially available SFC gearboxes. The standard with 1st at 50% and the close ration box with 1st at 52%. Marnix will correct me if I'm wrong. Then there's the early ones with a 650 main shaft which has a 19 tooth fixed sprocket.
Only the 5th gear on main shaft has needle roller bearings. The others are steel/steel.

I much prefer the SFC gearbox on the track. SF is totally inappropriate with 1st gear too low and big gaps between ratios. You only get off the line once.

Paul
 
There were 4 different SFC gearboxes. Early SFCs had either a standard SF gearbox or indeed the somewhat closer ratio early GT gearbox, both with plain bearings on the sleeve gear.
Then there is the usual SFC close ratio gearbox which was available with a plain bearing version (bronze bushes) and needle bearing version. There also was an optional gearbox with an extra tall first gear. SFCs with this gearbox were stamped ‘CC’ (cambio corse).

Marnix
 
I much prefer the SFC gearbox on the track. SF is totally inappropriate with 1st gear too low and big gaps between ratios. You only get off the line once.
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I never liked the CR boxes for the racing that I did - it was usually short races and, if you didn't get away with the leaders, then you had little chance of seeing them again. I never found any problem with the std SF ratios, but I always went for a good spread of torque rather than ultimate BHP.
 
phil37 said:
I never liked the CR boxes for the racing that I did - it was usually short races and, if you didn't get away with the leaders, then you had little chance of seeing them again. I never found any problem with the std SF ratios, but I always went for a good spread of torque rather than ultimate BHP.
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That's because you're a fast rider Phil.
Whatever I do, whatever the gearbox, I'll be behind.

Paul
 
phil37 said:
I never liked the CR boxes for the racing that I did - it was usually short races and, if you didn't get away with the leaders, then you had little chance of seeing them again. I never found any problem with the std SF ratios, but I always went for a good spread of torque rather than ultimate BHP.
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In endurance racing your start depends more on athletics and the strength in your legs than the ratio of first gear. 😉
Marnix
 
I used 19/48 at Lydenn on TOG, barely broke 110MPH, but it did catch me out at the hairpin during a wet race, very easy to lose the rear wheel and I did, I have the pictures taken by a pro but they are on slides FFS
CLEM
 
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