History of SFC1000

[Laverdalothar]

Uwe Witt at that time offered sets of double springs for the valves and I think also a different cam (?!?), which they seem to have used on the TT1 racer most probably. With that, higher revs should have been possible. Never the less, on standard 1000 SFC's, I would assume they have a hard time hitting 8.000 or beyond.

 

[Vince]

Glancing at my phone GPS a few times at what I call high speed has put a lot of the high 200-plus stories I hear to bed. Just the time those glances took gave me the heby gebes. And ain't happening again with the state of road surfaces allegedly remote enough to allegedly hit 7k in top gear.

 

[andre g]

just made a foto of what my dashbord stored.
Max. speed was at Kemmel Straight in Spa, max. revs in any lower gear.
It was with my 1000cc SFC engine, P1 cams and 36 Dellortos.

 

[Laverda1000.de]

Guzzi of the same ilk with 16” front never had that issue, those manufacturers had that sorted.

But still rode like crap. LeMans IV was a big step backwards.

 

[piranha-bro2]

just made a foto of what my dashbord stored.
Max. speed was at Kemmel Straight in Spa, max. revs in any lower gear.
It was with my 1000cc SFC engine, P1 cams and 36 Dellortos.

Very odd combination of revs and speed, Andre. 23.2kph/1000 revs. 4,000rpm in 5th would give you 93kph. Something doesn't look quite right - unless you're running about a 48T 530 rear sprocket with a std 19T front.

And 9,700 on a triple? Seriously?

 

[Laverdalothar]

Very odd combination of revs and speed, Andre. 23.2kph/1000 revs. 4,000rpm in 5th would give you 93kph. Something doesn't look quite right - unless you're running about a 48T 530 rear sprocket with a std 19T front.

And 9,700 on a triple? Seriously?

As Andre wrote, the 9.700 was in a lower gear. Both values are peak values of that trip in SPA and the Straight is VERY long, the bike and the rider VERY fast and light... ;-)

 

[Tippie]

A very long straight with a very fast and light rider and in a lower gear to boot. Just like holding full throttle in neutral and seeing what might happen. Maverick Vinales?

 

[piranha-bro2]

A very long straight with a very fast and light rider and in a lower gear to boot. Just like holding full throttle in neutral and seeing what might happen. Maverick Vinales?

I think Lothar means that figure of 9700 was recorded during the recording period, so could have been 2nd gear somewhere (am I right Lothar?). So the readout is basically a data logger of max speed and max revs attained during a session? Sorry, I read it as 9,700 in 5th at 225kph!

But that's still conrod and engine destroying RPM in any gear.

 

[andre g]

Yes it was a 1000 SFC triple. This engine with P1 cams had a real race character. At about 8000 rpm it got a kick and turns up to 9000 + very quick. Did not really see when it does the 9700, but definitivly not in neutral, maybe in 3rd gear and I know it is to much for a triple. But the dashboard stored the highest rpm ever. Normally I turned it up to 9000 rpm. max! On a test bench it had 102 HP at 9000 rpm at the back wheel.
Highest speed was on Kemmel straight with a slope between 4-6% uphill.

And yes, one day the crank was gone :-(…..

It was repaired, crank lightened and balanced by Gijs, Carrillo Rods, 78 mm pistons, same head and cams- but the character is gone. I did not find key so far.

 

[iis_iis]

There was a known to all usual suspect in Victoria ( Australia ) whom reported to me the iis was "cutting" out.. his RGS instrument pod ended up with me, it was reading 25% or better low on the rev counter, he was hitting the 8250rpm iis rev limiter ( used a staged recovery ramp out of the rev limiter ) my estimate it was shooting through the rev limiter on crank inertia to a guess of 9Krpm.

The 120 motors would regularly hit a rev limiter in the 4 lower gears, have no knowledge about 5th however. The 180 motors seemed to self rev limit, rarely if at all banged the rev limit on modified 180 motors, as the revs rise they sound like about to self destruct and the right hand does promote fear and spares the 180... besides the 180 "seems" to have plenty of torque though may well be less than a 120 motor... perception is reality.. j.

 

[piranha-bro2]

Glad I ran the 5000rpm test of the ZXR tacho using the Ignitech function - very accurate - was over-reading about 5% so the correction function sorted that - if only their cylinder advance correction function left/right worked. Set rev limiter to 8,200.

 

[Laverdalothar]

I think Lothar means that figure of 9700 was recorded during the recording period, so could have been 2nd gear somewhere (am I right Lothar?).

You are, that was my understanding of what Andre wrote.

 

[3CBRG]

There was a known to all usual suspect in Victoria ( Australia ) whom reported to me the iis was "cutting" out.. his RGS instrument pod ended up with me, it was reading 25% or better low on the rev counter, he was hitting the 8250rpm iis rev limiter ( used a staged recovery ramp out of the rev limiter ) my estimate it was shooting through the rev limiter on crank inertia to a guess of 9Krpm.

The 120 motors would regularly hit a rev limiter in the 4 lower gears, have no knowledge about 5th however. The 180 motors seemed to self rev limit, rarely if at all banged the rev limit on modified 180 motors, as the revs rise they sound like about to self destruct and the right hand does promote fear and spares the 180... besides the 180 "seems" to have plenty of torque though may well be less than a 120 motor... perception is reality.. j.

I ran a stock RGS to the limiter in 5th when cops were chasing me on freeway. Thought they were thugs. Turns out I was right.

 

[rocketonarail]

I remember Richard Slater presented me with a couple of bent valves half way through the rebuild of the Mirage ........ Must have hit some sort of rev limit at sometime or other , although had no particular recollection of it .......missing a gear accelerating down the M4 slip road on one occasion maybe , but can`t be sure ........

 

[iis_iis]

"Kissing" poppet valves, seen a few, ding marks on the valve edges, big valve heads for one. j

 

[rocketonarail]

These weren`t visible to the eye ........ and not sure about any ding marks ....... he reckoned they only came to light when he stuck them in an electric drill ........ After 112,000 miles they were going to be replaced anyway .......

 

[chrisk]

I remember Richard Slater presented me with a couple of bent valves half way through the rebuild of the Mirage ........

That reminds me ….. I used to knock around with a bloke that repaired washing machines.

Bern carried a burnt out timer in his toolbox, part way through the repair he’d present it to the lady of the house and the repair price escalated accordingly.

 

[iis_iis]

I ran a stock RGS to the limiter in 5th when cops were chasing me on freeway. Thought they were thugs. Turns out I was right.

Mazing, same all over the world, ditto on my Suzuki GT750K, night time chase, thought the idiots behind me were bikers, they were, Bankstown Highway patrol ( for the locals here ), outran their poxy Honda 4 Kwhatevers, i stopped quicker than they could, they kicked my bike over, beat me up, threw me in local lockup and beat me up one more time for good measure, real hero's of our police force. Then held me over for court the next day, speed dangerous and driving in a manner dangerous to the public, mandatory 6 months goal, nice.... had a solicitor turn up in his Maserati...the rest was history, section 256 ( 10 these days ), offence proven no conviction recorded, or slammer for 6 months... j

 

[chrisk]

Mazing, same all over the world, ditto on my Suzuki GT750K, night time chase, thought the idiots behind me were bikers, they were, Bankstown Highway patrol ( for the locals here ), outran their poxy Honda 4 Kwhatevers, i stopped quicker than they could, they kicked my bike over, beat me up, threw me in local lockup and beat me up one more time for good measure, real hero's of our police force. Then held me over for court the next day, speed dangerous and driving in a manner dangerous to the public, mandatory 6 months goal, nice.... had a solicitor turn up in his Maserati...the rest was history, section 256 ( 10 these days ), offence proven no conviction recorded, or slammer for 6 months... j

One of the pitfalls of trying to evade the cops on a twostroke, is that, while they may not be able to see you, they can smell where you’ve been.

 

[piranha-bro2]

Know all about the chase - knew they were cops but could have been thugs in an unmarked car - Darwin 1975, speed dangerous to the public, manner dangerous to the public. Didn't beat us up but a night in the pen and they rode our bikes back to the cop shop. Didn't attend the court hearing - was already in Perth by then.