Comments on: Ducati is Stuck (News)

By: Jonwawa

Jonwawa — Tue, 23 Aug 2011 12:28:16 +0000

Put Simoncelli on the Ducati with Rossi, The crown will thus pass to the new italian champione….. and the world will be much hairier!!!!

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By: Norm G.

Norm G. — Tue, 16 Aug 2011 01:11:33 +0000

re: “It hasn’t been easy or cheap in aerospace.”

nor should it be. nothing of value ever is. it’s why i’ve contended from the very first valencia test to NOT look for anything out of ducati nor rossi during transistion year 2011. they have neither the time nor resources to successfully conduct the R&D in the unrealistic timetable given by rabid fans and laymen. here we are 1/2 way thru august and i’m batting 1,000.

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By: Norm G.

Norm G. — Tue, 16 Aug 2011 00:58:07 +0000

re: “BTW, Dymag sucks.”

whose talking about dymag wheels…? i’m talking specifically about a little known C/F swingarm prototype designed for the 1st generation R1′s that actually never went into production. be wary of “throwing the baby out with the bathwater”. it’s how we miss things. it’s how we overlook the answers to our problems that are often right in front of us.

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By: Norm G.

Norm G. — Tue, 16 Aug 2011 00:50:28 +0000

re: “You say the superiority of the motor is being masked by a recalcitrant chassis, I say the motor’s layout is what’s preventing the chassis from working- it’s essentially the same thing. The combination of the L-4 with the frameless carbon chassis is not working.”

well then the answer comes down to “what’s cheaper to tool up for”…? molds and an autoclave…? or scrap 25 years of data PROVEN successful, millions if not billions (with a B) dollars invested, design an engine from scratch and start all over again taking bets on how it all comes out…?

mind, not a trick question. you don’t need to hold a CPA to answer this.

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By: Bob

Bob — Mon, 15 Aug 2011 17:10:57 +0000

Norm, you said a whole lot but actually haven’t said anything. You make references to “it”. “It” has been done by BMW, the A109, Dymag… Ok, take a look at what? What the hell is “it?” What did any of these guys do besides fabricate something out of CF? What is this technique you speak of? And what is the problem you speak of that this technique is employed to? You don’t mention any of that at all other than pointing out names of companies that use CF.

Any joker can make something out of CF. I’ve done it. My first CF parts were full sets of bodywork for my landspeed bikes. After that, some smaller parts. Not a big deal at all.

None of the sources you cited ever made a motorcycle chassis to handle and engine that revs to 19000 rpms, so any solutions to a problem they ever dealt with were not the same problems nor solutions. So you can’t say that Ducati needs to look at these companies for a specific solution to their problems.

BTW, Dymag sucks. I’ve seen a dozen of them come apart from the hubs at the track, causing the rider to crash and completely destroy the bikes and seriously injure the rider. For normal street riders, they’re not trustworthy, because after 10s of thousands of miles on a bike that weighs 100 lbs more than a racebike and riders who likely weight 50+ pounds more than a top level racer and on roads that are a lot rougher than a track, the average street rider doesn’t have the equipment to x-ray the wheels to check for delamination between layups. You don’t see CF wheels in MotoGP for a reason.

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By: Dave

Dave — Mon, 15 Aug 2011 15:07:14 +0000

That’s the tricky part of CF. It’s not a material with set properties the way metals are. With alumuinum and steel you have properties that must be designed around. With CF, the engineers have a lot of control over the properties of it (lay up schedule, resin types, etc.). It’s literally rocket science so it’s going to take a while to figure out. Ducati’s aches are caused by having to develop it in competition (and losing).

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By: kirk66

kirk66 — Mon, 15 Aug 2011 13:52:33 +0000

I (not an engineer) believe the issue of feel is directly related to the fact that the material used in the CF doesn’t transmit enough force/flex/vibration for the rider to understand what the bike needs in the turns. Since motors don’t bend the feel is left to very small sections of the frame connected to it. CF has a kind of “tunable” flex, but if you can’t get any “feel” then you don’t know where to tune the frame. The cost of a traditional aluminum frame is much less than the CF and there is a way to tune it in similar ways to the CF.
I think Ducati could use a combination of Aluminum and the Ducati faithful trellis design. The trellis hanging the motor could be the trick in tuning the frame. If the main spars are rigid and the trellis has flex it may help the riders get the “turn in” feel that they are looking for and the traction needed upon exit. But I’m not an egineer. So, I may be overlooking some obvious faults in this idea.

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By: Ruefus

Ruefus — Mon, 15 Aug 2011 08:58:41 +0000

Gee…since I’m not no engineer, I muss-be a billy bob speakin’ out his butt. Really? It’s more expensive to manufacture? Gawrsh…I had no idea.

Never said carbon was more predictable or even AS predictable. I said it’s fabricated to a specific purpose. Metal can be as well, but not in nearly the range that carbon can be ‘tuned’. Given the millions of parameters, getting it ‘right’ is much harder with carbon.

Now, to your ‘obvious’ statement.

Considering I’ve been around the fabrication of carbon fiber, the various lay-up procedures, the application of resins, vacuum bagging and the use of autoclaves etc. but don’t have a degree makes me just a billy bob, right? Or is it obvious someone besides myself is a billy bob here?

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By: Kit Halsted

Kit Halsted — Mon, 15 Aug 2011 07:30:00 +0000

Okay, let me rephrase…

IF you want to make a “frame” from a short carbon fiber box and an engine,

AND you want that “frame” to emulate two long, skinny aluminum spars,

THEN your engine’s layout must be compact enough that its position can be tuned with the other parameters.

That was my takeaway from the article.

The Ducati L-4 may be superior in some ways to the other motors, but it is decidedly inferior in flexibility of placement, and flexibility of placement is exactly what they need from it in order to work with the CF “frame”.

You say the superiority of the motor is being masked by a recalcitrant chassis, I say the motor’s layout is what’s preventing the chassis from working- it’s essentially the same thing. The combination of the L-4 with the frameless carbon chassis is not working.

As for Stoner riding it to victory, well… Can’t say I’m a big fan of his, but I have to give him credit. He’s winning by seconds, not tenths, on the Honda this year.

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By: kpaul

kpaul — Sun, 14 Aug 2011 22:57:02 +0000

See below several of us engineers have talked about the differences between CF and metal. If you mean feedback as in deflection rate than CF doesn’t deflect as much with the same force applied. I had one of the early CF frame Trek bikes. It definitely had a duller less road feed back feel compared to my aluminum bike. “In general, Carbon Fiber is stronger, and is lighter than aluminum, steel, or titanium. It can be produced in a variety of shapes, but at much greater cost compared with sheet metal parts. Carbon fiber must be molded, set, epoxied (about equivalent to aluminum), then autoclaved, cured and assembled. So it costs a great deal more in terms of the facilities required to produce it, as well as the time required to assemble it. The upside again is it’s strength and light weight. In addition to this fact, however, Carbon Fibre has a certain natural damping quality to it. Vibrations are not transmitted through carbon composites with the same fidelity as with metals, making it useful as something of a shock absorber in the wings.’ From an aerospace expert

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