SF 1 infomation

As mentioned on Facebook Fitz, if the photo of the carbs you posted there is from that bike, it ain't an SF1. You cannot fit 30mm VHBs on an SF1 head.

Paul
 
Fitz, I wouldn't be too concerned about the bike not coping with the rigors of racing, potentially spoiling it's heritage. After 14 seasons racing I stripped my SF2 to replace the rods (from concern for their age - 80,000 road km then all the racing). Albeit an SFC crank, but an SF with Carillo or similar would never cause concern. The only minor issue was the bronze bush in first gear a bit loose - from countless race starts no doubt. These are not fragile bikes either in the motor or the chassis and they are so very rewarding to race. My mate here has similar experience with many seasons racing. When I hear people fearing that a potential purchase might have been raced I know they can't be referring to an SF.
 
Crime of the century - Dave Fitz mistakes his new Lav model - it looks like its an early SF, big Lav drum brakes with air scoops, VHB flat slide carbs, f'''''g rivet counters !!!
 
Piranha Brother 2 said:
I really doubt you'd want to take an SF1 onto the track with the std drum brakes.
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Why not you?d be in historic p3 here I think racing the same sort of shit, racing is about extracting the most of whatever you?ve saddled within in your talent spectrum, not about being comfortable, there called track days....
 
Had a few rip snortin track days on my stock sf-1 up at Broadee... 8) no brake fade, just a stretched cable that was remedied during the day with the adjuster..... it?s all about the flow as you know  ;)
 
"750 swingers (excepting SFC) have the same bearing/frame dimensions as the 180? triples, all bits are interchangable.  Needle bearings unfortunately don't last forever either.  Bushes are better, but are usually shot through "over-maintaining" ::) by now.  Nought wrong with the rubber bushes (if fitted) if they aren't perished, except maybe for racing."

from Piet, this is easily proved as the triple disc brake swing arm is the same part number as the SF3 disc braked swing arm.

and Fitz 
"I am told there a lot of rare parts fitted, the brake hubs have air scoops to drag air into the hubs and brakes, all patented Laverda designs I am told"

look a bit more closely and you will see that cooling air is scoopd in at the front but passes over the hub and out through the radial slot inside the spoe circle and at the back the little gravel pit scoops get the air on to the outside of the drum before a similar exit not INTO the drum. It was a good idea at keeping the wet out of the drum under rainy conditions, but it didn't work in that respect and didn't provide much cooling either, no matter how well you set up that front brake, hard braking from say 80MPH will get you right down to about 20MPH (but only once) and from 20 to zero will as likely as not kill you. Been there and done that (six days unconscious and six months in hospital) if it had twin Brembo's thing would have definitely bee different.

CLEM
 
Thanks Clem, see you can't argue with that can you. It's funny when you read things about the fantastic Laverda this that and the other then you find somebody with actual experience

Has anyone used the extended clutch arm I have found on't Thebay from Giovanni motors, looks like a simple fix. I havent got round to inspecting it yet but it feels seriously heavy as it stands

Got the swing arm out and its quite a good design I think. The bushes are buggered and the spindle doesnt look too healthy but they are available. I like the scrolls on the spindle to help the grease get around. I don't see any need for needle rollers now I have seen it in my hands. The problem nwo is how to get the bushes out, I have already tried a little heat and a drift but that's obviously not the way to go - swing arm 1 Fitz nil
 
the extended clutch arm
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Sometimes checking the routing will solve the problem.
Disadvantage of the long arm is that you'll have to cut a slot.
Though there is also a type that doesn't need the slot:
https://damclassicracing.com.au/43301003-1-dam-easy-clutch-mk1_std/
I know that OCT (Germany) sells them, too. octeam.de

Ernesto
 
Fitz said:
Thanks Clem, see you can't argue with that can you. It's funny when you read things about the fantastic Laverda this that and the other then you find somebody with actual experience

Has anyone used the extended clutch arm I have found on't Thebay from Giovanni motors, looks like a simple fix. I havent got round to inspecting it yet but it feels seriously heavy as it stands

Got the swing arm out and its quite a good design I think. The bushes are buggered and the spindle doesnt look too healthy but they are available. I like the scrolls on the spindle to help the grease get around. I don't see any need for needle rollers now I have seen it in my hands. The problem nwo is how to get the bushes out, I have already tried a little heat and a drift but that's obviously not the way to go - swing arm 1 Fitz nil
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There a shedload of people on this forum with experience, Fitz. I can tell you practically anything you want to know about an SF1, 2 or 3. I can tell you that it's a piss easy fix to make the clutch lighter - if cutting a 3 or 44mm slot in your clutch cover offends, go with the dog-leg as found via the link to DAM Classic. i can tell you that you can slow down an SF1 with it's drum brakes, but if you want to race it in historic, there will be lighter drum brake bikes that will leave you for dead under brakes. I can tell you that I ran off the road as a 19yo on mine when it simply didn't scrub off enough speed before a bend. I raced it, but by then it had a 4 leading shoe Yamaha racing brake on it and I outbraked a green frame at the end of 180kph main straight in probably my second ever race. On the original brake I would have been half a lap down by that stage.

People ride these bikes for different reasons and at very different speeds, some tootle, I like going fast - but I don't like unnecessary risk. Sure, Cosi, we have ride to any bike's limits, but it's kinda nice if those limits are at least close to your competitors.

Is someone gonna pipe up and tell me all those fantastic pics of SFCs when the factory campaigned them in the early 70s show massive 4LS Fontanas or whatever they may have been because the SF brake was too good? Gimme me a friggin break.
 
Is someone gonna pipe up and tell me all those fantastic pics of SFCs when the factory campaigned them in the early 70s show massive 4LS Fontanas or whatever they may have been because the SF brake was too good? Gimme me a friggin break.
 
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:D :D :D
 
Ceriani, 230mm, 4ls, magnesium. Offered as an option, ex factory.

Friend of mine used to race a first series SFC first half of the 70s. He put a pair of discs on it.

Paul
 
Paul Marx said:
Ceriani, 230mm, 4ls, magnesium. Offered as an option, ex factory.

Friend of mine used to race a first series SFC first half of the 70s. He put a pair of discs on it.

Paul
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But I guess he kept the points ignition, seeing as he is still your mate 😂
 
Tippie said:
But I guess he kept the points ignition, seeing as he is still your mate 😂
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Wasn't much else available in 74/75. Boyer maybe?

The bike has since of course been restored with a drum at the front.

He doesn't ride any more. He got so badly smashed up racing that he has trouble walking now.
He has an endurance racing triple which he stopped using because it was being banned from the track due to noise limits.

Paul
 
Tippie said:
No good getting busted up. Yes noise limits on track here are stricter than road but we manage to get them quiet enough.
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Friend in question didn't want to quieten it so he just retired the bike.

Paul
 
I'm still pretty amazed at the noise produced by plenty of bikes on track here in Oz. The Irving Vincents, Red's Mule to name two ... it's nice that there are race days where they let you ride anything. Even track days at Broadford where Maurice says he can run his '74 SFC with the fully unfettered 2/1. Just don't go to a Ducati Club track day at Phillip iIsland - even your Lafranconis will fail the noise meter at the end of the main straight. Ask me how I know.

Making bikes quiet but breathing sweetly is a tricky affair - going through it myself at this very moment with the SFQ 2-1-2 system ... which may or may not be a success! An expensive and time-consuming exercise if the latter prevails.

Paul, I hope your friend didn't get injured because he ran out of brakes!!
 
My one and the only use of a TZ 4 leader was on a Bultaco improved tourer road race bike, the precursor of the Superbike class. Long term project of a mate, I wanted a ride. He had made himself 2 expansion chambers for it, a touque one and a top-end one. No idea what was on it, so on a nice quiet Sunday morning in leafy Grenich a Hourbour side upmarket suburb he let me do a lap of the block on this bearly muffled thing. So off I go in shorts and a T-shirt and typically ZERO warning on anything this bike might do. So I take off in 1st and it goes onto the pipe and really moves out, I was used to 2 strokes so expected this. I pass some old bloke walking along and he shacks his fist at me, ok its loud but so are lawnmowers. I then arrive at the right turn at the end of the road moving along pretty well, maybe 70 or 80ks and apply the brake. Nothing happens and I am still approaching this bend, so I go harder on the brake and then it happens. The forks dip hard and I am trying very hard not to end up kissing the front guard. Talk about grabby, it had nothing or full power and bt full power I mean rear wheel in the air stuff. Apparently they require some heat and then this servo as thing happens. I have no idea how many stops it had in it but my hell it was strong. I warning from the owner would have been nice, it got put away after that before the cops arrived. There would have been plenty of phone calls in the 5 minutes it was going.
 
Piranha Brother 2 said:
Making bikes quiet but breathing sweetly is a tricky affair - going through it myself at this very moment with the SFQ 2-1-2 system ... which may or may not be a success! An expensive and time-consuming exercise if the latter prevails.
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Take a look at the Britten Quentin.  I was simply amazed seeing it run at Daytona in the BoT race 1996.  Loud-as-fuck Guzzis and Ducatis hardly made it half-way up the banking for lack of power/speed, the Britten would whistle around at the very top, half as loud but twice as fast as the competitors (at least it seemed like it)!

Adapting anything from a state-of-the-art V-twin to our old clunkers would be a real challenge, but it's proof it can be done.

piet
 
sfcpiet said:
Take a look at the Britten Quentin.  I was simply amazed seeing it run at Daytona in the BoT race 1996.  Loud-as-fuck Guzzis and Ducatis hardly made it half-way up the banking for lack of power/speed, the Britten would whistle around at the very top, half as loud but twice as fast as the competitors (at least it seemed like it)!

Adapting anything from a state-of-the-art V-twin to our old clunkers would be a real challenge, but it's proof it can be done.

piet
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Too true, Piet. i think the Britten had some sort of boom box apparatus under the motor that exited under the seat? Clever motorbike that one - if anyone wants a great read, get the book 'Britten' - details the thousands of hours of flowbench development time that went into it. I'm guessing the exhaust received plenty of attention as well.

Vince, the TZ 4LS brake on the Lav was incredible when set up properly by a race experienced person, with new linings. It had great feel and power. As it wore the on-off thing began creeping in. Not so bad on a 200kg+ SF but on a light bike???  :o
 
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