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Discussion Starter #1 (Edited)
Finally got my bike onto a track where it could really stretch its legs. My normal track is Toronto Motorsports Park, which is on the tight side. I can get pretty deep into fifth gear on the straight, but most of the track is second gear with brief moments into third.

Yesterday I ran at Mosport with the Ducati Owners Club of Canada. Mosport is a *serious* track where they run American LeMans cars, etc. Very fast and flowing, lots of big elevation changes. It was actually kind of thrilling to run there because it holds a lot of memories for me as a spectator, watching Can-Am cars and the like back in the late 70s and early 80s with my Dad.

Anyway, I never used lower than third anywhere at Mosport, and most of it is fourth and fifth. And, at the end of the very long back straight (which actually isn't that straight...), I am just approaching the rev limiter in 6th, but it's not going any farther. I am running a fairing and 14/41 gearing. I think a skinner guy with a better tuck could just hit the limiter with that setup, given enough space. In fact I think I could too if I really tried.

So, whatever 14/41 @9000 rpm is...that's how fast it can go with my setup. I had my speedo taped over.

What a weird experience though - that is so fast it just feels surreal. The bike is absolutely wailing at over 8000 rpm for many, many seconds and the scenery is going by like mad. I guess it *should* be fun but the whole time I am just thinking "if this thing decides to swallow a valve right now I am a goner". Way too scary to be enjoyable. However, I was keeping track of my lap times to see how I was improving, and there's no point doing that if you aren't going to pin it all the way up the straight. So pin it I did.

For the folks worried about "losing top speed" by shortening the gearing....a) you won't, and b) it doesn't matter. You aren't going there anywhere but on the track unless you are certifiable.
 

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Sounds fun. I was at Autobahn Country Club Racetrack this past weekend. I think the temperature was higher than my highest speed on the South Track..it was 100F.
 

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Discussion Starter #5
Sounds fun. I was at Autobahn Country Club Racetrack this past weekend. I think the temperature was higher than my highest speed on the South Track..it was 100F.
Never heard of that one, so just looked it up. That looks like an awesome track! 15 turns, 2.1 miles, and 40 feet wide. Up to 3.6 miles if they link the North and South. Wow. How's the surface?

I don't think we have anything in Canada that can really compare to that, except maybe Calabogie. Haven't been there yet.
 

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You are about right on. I've been followed and filmed at around 145. I run similar gearing. I'm headed to the dyno this week and will comfirm many things, one of which is a top speed without wind...

I'm adding DucShop velocity stacks and hoping to elminate the serious lean condition I have with the rear cylinder. Adding the PC5 unit. I hope the 14-003 unit is the correct unit as I've had it ordered. Dynojet shows no crossover for the PC V on this bike model but we know many have used it on SC and Hypers.

Once the work is done I will post all dyno results before and after. I had some head work done, minor P & P with 5 angle valve job and tremis with DR flashed ECU from Gotham. The most recent dyno yielded 77hp but the rear cylinder was way out of stioch and very very lean at mid-max rpm/max hp. Also is was excessively lean at lower rpm.
 

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Hi,
I Like the Autobahn-Club very much! The PS with its big screen is perfect for full-speed-left-side-riding for many miles. My free breathing beauty goes with stock gearing in the 6th gear a little bit more than 8000 rpm, that means around 150 mph.

Sent from my HTC HD2 using Motorcycle.com Free App
 

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I'm told (ex- racer and mechanic who preformed the work) my bike with existing setup should be good for 155mph. I've yet to see that, I'll soon find out with a GPS lap timer and a good launch out of T10 at Summit Main. I think 150 will be pushing the limits. Gearing may help, I think the stock tall gearing may be a requirement. It just sucks on the street having too tall a ratio around town.
 

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I rarely use 5th or 6th gear on mine, even on our local track I am throwing the anchor out at 115 on the main straight! From the first service I have been running 14/39 on my SC Mono as it was an easy mod.. I am due a new chain soon; how does the 14/41 you are running compare for street use?

Thanks

R
 

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Holy cow guys! What are you doing to get a DS1000 up to 150? My S2R1000 hits the wall at about 135. Are you talking mph or kph. :)
 

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Holy cow guys! What are you doing to get a DS1000 up to 150? My S2R1000 hits the wall at about 135. Are you talking mph or kph. :)
I've seen 145mph on the clock with more to go and backed off - these are very strong motors - I suspect the gearing on a monster is very different to the SC - which is very stable incidentally at those speeds!
 

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I've seen 145mph on the clock with more to go and backed off - these are very strong motors - I suspect the gearing on a monster is very different to the SC - which is very stable incidentally at those speeds!
I think internal gearing is the same. I run a 15/42 final gear. I thought you guys were talking real mph as opposed to speedo mph. My bad. :)
 

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I think internal gearing is the same. I run a 15/42 final gear. I thought you guys were talking real mph as opposed to speedo mph. My bad. :)
LOL :D Yeah, I'd like to see those +120mph numbers backed up by radar or laser.
 

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Discussion Starter #14 (Edited)
Personally, I was talking real mph, not indicated. It might be off a tiny bit depending on rear tire diameter, or if the tachometer is off somewhat. The 142 number was calculated from the rpm and gearing ratios, using the Gearing Commader. I'll bet it is close.

I am running an Airtech fairing similar to the PS / 1000S units, and have some typical intake and exhaust mods, I can't believe an SC making near stock power could go anywhere near that fast without a fairing. Aerodynamics are *really* important at that speed. A monster with the same motor would suffer in that regard.

I was very close to aero-limited top speed at the end of the straight in sixth (i.e., throttle pinned and speed only increasing *very* slowly if at all), which was also just a tick off the 9000 rpm limiter (DP ECU). I wonder if taller gearing would actually be better (?) since the motor would then be at its power peak, rather than past it, at the point that acceleration ceased due to aerodynamic resistance? I admit that I am not clear on that.

The importance of aeordynamics was made clear to me recently when I gained over 3 s per lap at my home track just by putting the fairing on - and that is a slow track with only one straight that lets me get into 5th at all, let alone 6th.

So yeah, I'd be surprised to see an S2R1000 do much over 130 mph without a more substantial fairing.
 

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Personally, I was talking real mph, not indicated. It might be off a tiny bit depending on rear tire diameter, or if the tachometer is off somewhat. The 142 number was calculated from the rpm and gearing ratios, using the Gearing Commader. I'll bet it is close.

I am running an Airtech fairing similar to the PS / 1000S units, and have some typical intake and exhaust mods, I can't believe an SC making near stock power could go anywhere near that fast without a fairing. Aerodynamics are *really* important at that speed. A monster with the same motor would suffer in that regard.

I was very close to aero-limited top speed at the end of the straight in sixth (i.e., throttle pinned and speed only increasing *very* slowly if at all), which was also just a tick off the 9000 rpm limiter (DP ECU). I wonder if taller gearing would actually be better (?) since the motor would then be at its power peak, rather than past it, at the point that acceleration ceased due to aerodynamic resistance? I admit that I am not clear on that.

The importance of aeordynamics was made clear to me recently when I gained over 3 s per lap at my home track just by putting the fairing on - and that is a slow track with only one straight that lets me get into 5th at all, let alone 6th.

So yeah, I'd be surprised to see an S2R1000 do much over 130 mph without a more substantial fairing.
Yes, I think I could see the fairing making 140 or so possible. On my monster even wrapped around the tank so tight I can't see where I'm going it takes forever to gain any speed much past 125 or so.
 

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It's all about airflow. Having switched from an unfaired biposto to a faired Paul Smart I can vouch for at least +15mph of comfort at speeds over the ton, and I've accidently hit 125 a coupla times with plenty of rpm to go. I'm sure she'd do well over 140.
 

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It's all about airflow...
Exactly, which is why race bikes have aero-packaging. And YD made another important remark, the top speed that is limited by aerodynamics. I can't believe a stock, Paul Smart faired SC could go past 140-150mph and certainly not an unfaired bike.

I wonder just how accurate our speedometers are, particularly when the needle wanders into that higher speed territory on the gauge. That's what I was talking about with radar/laser backup. The Gearing Commander et al. are mathematical so I don't doubt the speed it returns. A dyno could give the top-speed as given by the limits of the engine/drivetrain but it would be higher than what would be possible on the open road due to aerodynamics in general (this goes for any vehicle).
 

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From previous experience, I'd say that most speedos (except German ones) are slightly optimistic, ...and the UK laws allow +/- 10% (+ 3mph) on speedo accuracy when it comes to fines...
 

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And we can add this

We Have Data For That
I have a tire-slip question. If a typical sportbike is running down a straight section of paved road at 150 mph, how fast is the surface of the rear tire likely to be moving?
Robbie O'Rourke
Los Angeles, CA

On a race-prepped Suzuki GSX-R1000 with Pirelli Supercorsa DOT race tires, our Racepak data acquisition shows tire slippage of about 5 percent at 150 mph on Willow Springs' front straight, for a rear wheel speed of 157.5 mph. We calculate slip by comparing GPS speed with wheel speed, although to be accurate the bike must be upright (because of the changing tire circumference at lean angles) and tire deformation can be a factor. Here are some additional numbers for thought: Heading up the hill toward turn 6 at Willow, tire slip with the bike vertical is greater than 10 percent at 85 mph. In some turns, taking into account wheelspin as well as the smaller tire circumference, slip can be as much as 40 percent. Under braking, we typically see negative slip between 15 and 20 percent.

Read more: Ask The Geek: Aluminum Alloy Materials - Sport Rider Magazine
 
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