Elvington 1.25 mile top speed run, 11/12 Oct

sfcpiet said:
I'd give it a try without the stacks... or use shorter ones. Check out the shape of Reds racing intakes, way to go!

An hour or 2 with the carbs on a flow bench will most probably unleash a couple of ponies.

piet
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Its going on the dyno soon, so i may get the chance to try and optimise both setups.

There's a lot i could have done but at least i came home with a running motor which is a priority.
Rob
 
I suspect it's now a case of needing more HP in order to obtain a higher speed and that presumably will invoke the law of diminishing returns in the attempt to find the 10 extra mph you were after?
I hope you manage it - and manage to keep the engine in one piece.
 
Hi Andy
I cant create enough horsepower but i have some options.
Red pointed out, one "now" obvious point. Keep the same gearing 19/38 but increase the rev limit. I have my reasons atm not to but thats a logical step, see attachments.

Piets comments also as valid.

Build a more streamlined fairing ( probably too much work for a small improvement ( the frontal area is already pretty good for a triple. Mudguard changes.
Check power at Dyno but likely its there already.
 

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I said a bit earlier, in the 125GP days, they used to send riders to Japan to learn how to sit in an aerodynamic way using wind tunnels. This was probably before those big back arches appeared on race leathers. Apparently, lifting your arse off the seat and arching your back helped reduce drag. Long, smooth seat rear tails also helped; check out cycling stuff as well. Aro is really counterintuitive. Lots of pre-WW2 aro looked effective but proved not to be. It's cheaper than blowing up engines. Well, probably not Dust Bin fairings, but they got banned
 
Vince said:
I said a bit earlier, in the 125GP days, they used to send riders to Japan to learn how to sit in an aerodynamic way using wind tunnels. This was probably before those big back arches appeared on race leathers. Apparently, lifting your arse off the seat and arching your back helped reduce drag. Long, smooth seat rear tails also helped; check out cycling stuff as well. Aro is really counterintuitive. Lots of pre-WW2 aro looked effective but proved not to be. It's cheaper than blowing up engines. Well, probably not Dust Bin fairings, but they got banned
Click to expand...
Probably because the Guzzi wind tunnel was too expensive to rent.
Paul
 
when we raced at The Bend last year in South Australia we ran a 19/40 sprocket combination, on a circuit track you gear for the corners at the back of the circuit, not so much the straight
We recorded a top speed of 241 klms, or 149.75 mph on the straight in our third race there

Rob, go to the dyno and see where your power curve starts to roll over, ours rolls just below 9,000 rpm so we have the rev limiter set at 9,500 rpm
There is more in your engine yet

I'll look at sending you some bits that may help, be cool to see you run 160 mph

Good luck
 
I can get the dual springs ok that you recommended but Im reasonably sure they wont work with the spring caps and seats that i use.
Do you have any pictures Red, of those parts ( caps and seats) that you use and availability?

Im running single springs and thats my reticence for going higher with RPM, might work great or might get messy.

What is the normal redline on the later motors for example sfc1000 and did they have dual springs from the factory?

Thanks.
 
Jota Rob said:
I can get the dual springs ok that you recommended but Im reasonably sure they wont work with the spring caps and seats that i use.
Do you have any pictures Red, of those parts ( caps and seats) that you use and availability?

Im running single springs and thats my reticence for going higher with RPM, might work great or might get messy.

What is the normal redline on the later motors for example sfc1000 and did they have dual springs from the factory?

Thanks.
Click to expand...
My SFC 1000 does not have dual springs but it revs up to 9000 rpm easily with P1 cams. The normal upper red line is 8500.
 
andre g said:
My SFC 1000 does not have dual springs but it revs up to 9000 rpm easily with P1 cams. The normal upper red line is 8500.
Click to expand...

In top gear at those sort of revs, my 81 Jota was rounded up by a club members Ducati 748 like I was standing still ☹️ …. the Barry Sheane arse wave as he went past was just plain demoralising 🙄
 
chrisk said:
In top gear at those sort of revs, my 81 Jota was rounded up by a club members Ducati 748 like I was standing still ☹️ …. the Barry Sheane arse wave as he went past was just plain demoralising 🙄
Click to expand...
Thing is Ducatis are not all the same, cooking versions are a mile from tuned or top spec variety.
 
I just had another look at your full fairing. How is it fitting and removing the lower section? The full fairing I had needed the front wheel jacked up, and it slid under the wheel. The whole thing started way low, so I cut the under engine bottom out and added approximately 100mm so I could get it high enough to be more comfortable. So much work, as I said, never again. It got replaced by a bevel Ducati one. Typically, still couldn't leave it alone. I had it made with twice the typical race thickness to avoid it being wobbly, approximately 3mm instead of the typical paper thickness. Is that a removable headlight plug on yours? That's bloody tidy.
 
Vince said:
I just had another look at your full fairing. How is it fitting and removing the lower section? The full fairing I had needed the front wheel jacked up, and it slid under the wheel. The whole thing started way low, so I cut the under engine bottom out and added approximately 100mm so I could get it high enough to be more comfortable. So much work, as I said, never again. It got replaced by a bevel Ducati one. Typically, still couldn't leave it alone. I had it made with twice the typical race thickness to avoid it being wobbly, approximately 3mm instead of the typical paper thickness. Is that a removable headlight plug on yours? That's bloody tidy.
Click to expand...
Hi Vince.

Thanks yes, i kept the cut out for the sfc headlight rubber, last used 2011, and last week, turned it into a 4 bolt plug that fits the headlight flange so theyre interchangeable.
Those sfc rubbers dont like duct tape stuck over them, i remember from before.

I did all the mods on the fairing. First involved cutting chunks out where Laverdas stick out, alternator, frame cradle, lower engine brackets, lower l/h primary cover. Then the whole floor since it simply sat too low.
Yes is thin in places, id say two ply and now 2 and 3 ply.
The bottom fits with dzus fixings. It can be removed or fitted in minutes, rear wheel on paddock stand, front wheel on a block 100mm. It'll slide out to the right between motor and front wheel.

The bars have to sit low down as a compromise to having a lower frontal area. I wanted it to look compact.
I have 2 steering lock plates so i can swap a regular in for a reduced lock plate ( for fairing).
 
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