Comments on: Ducati Cries Uncle . . . Will Test Japanese-Style Twin-Spar Aluminum Frame Next (News)

By: Norm G.

Norm G. — Tue, 04 Oct 2011 01:02:43 +0000

re: “Trellis can never compete with ’shell’ type structure”

trellis has already won a GP title… and did so while dominating.

Report this comment

By: Norm G.

Norm G. — Tue, 04 Oct 2011 00:53:03 +0000

re: “There’s a huge difference between production based Superbikes and Grand Prix machinery.”

WCE (worst comment ever)…! maybe 20 years ago in the 2-stroke era.

Report this comment

By: Norm G.

Norm G. — Mon, 03 Oct 2011 23:55:14 +0000

re: “There is a word in racing for people who think about the past. The word is loser.”

checa didn’t get the memo…

Report this comment

By: DynoSoar

DynoSoar — Mon, 03 Oct 2011 11:44:03 +0000

Actually Raymond, seems to work OK on Checa’s Superbike and a few other world championship winning motorcycles – be careful about your absolute statements when it comes to the balanced compromise that is motorcycle Engineering.

Steel has some advantages as the flex member in a chassis. The high fatigue loads it can withstand and the small volume of material needed to carry the loads around other components often make it easier to acheive a desired flex response and damping characteristic within a limited space and geometry, especially when prototyping.

I strongly suspect that the challenge here is that the relationship of flex and damping to feel is still something of a black art in motorcycle design. With tyre technology changing continuously, and a (currently) conventional aluminium beam chassis being the level playing field that offers the same performance compromise to every team, I applaud Ducati’s efforts to find some breakout approach that will move us forward to the next level. Unfortunately, they have clearly found some blind alleys the last couple of years.

Let’s not forget that people laughed at Colin Chapman and his ilk when they suggested that all chassis movement in a car should be in the suspension, but that idea opened the door for precision geometry and wider tyres. The fact that a similar approach patently won’t on a motorcycle is what makes bike chassis design so much more complex and interesting – and with so much more opportunity remaining for breakthrough changes. I have to wonder what the team would be building now if John Brittan had lived a little longer…….

Report this comment

By: joe b

joe b — Sun, 02 Oct 2011 18:19:42 +0000

sad to hear rossi say it wasn’t his fualt he fell, blaming Lorenzo and Spies, in the first turn at Motegi. dont they know, to get out of his way?

Report this comment

By: Raymond

Raymond — Thu, 29 Sep 2011 22:54:01 +0000

Steel trellis is too inconsistent to manufacture, and is too heavy, but most of all it is too stiff. Frames NEED to be laterally flexible (side to side, not length wise) for it to perform well when the bike is on its side in a corner. A motorcycles suspension does not work very well when going over a bump when the bump is leaned over at 50 degrees lean angle or more. Instead, the frame acts as the suspension, and if it is so stiff to not be able to flex while hitting a bump, this results in loss of traction.

Report this comment

By: Pete

Pete — Mon, 26 Sep 2011 17:34:56 +0000

There’s a huge difference between production based Superbikes and Grand Prix machinery Norm. Having ridden and raced both I can vouch for that.

Report this comment

By: brinskee

brinskee — Mon, 26 Sep 2011 00:44:57 +0000

Pit lane AND a time delay of 10 seconds. There’s only so much you can do while being caught in traffic. Even if you’re Vale. I’m not saying the changes to the bike were good, but a penalty like that would be tough for anyone to overcome. What was the expectation, that he fight all the way to the top five? Come on.

Report this comment

By: Denny

Denny — Sat, 24 Sep 2011 15:19:42 +0000

Absolutely: your rationel seems to be thought out. Trellis can never compete with ‘shell’ type structure, be it aluminum or steel. It’s beautiful and looks traditional, that’s about all. What is offering itself is a spacious tube-like structure. Steel is too heavy, so what is left is aluminum or composite while the former one has more chance to be stiffer. If I was to tackle this task it would look like extended ‘goose-neck’ (nothing to do with your nick) bolted right onto engine case. In fact I believe the best would be if the casing and frame was one and identical piece. That way the ‘stiffness’ would attain its highest value in given space. Conversely, to weaken it predictably for purpose of flex is well within current engineering tools capabilities. Some material to read on frame design is here:
http://www.docstoc.com/docs/76698788/Motorcycle-Frame-Structure—Patent-7845451

Report this comment

By: Norm G.

Norm G. — Sat, 24 Sep 2011 03:44:00 +0000

re: “Also see Casey Stoner’s opinon on the steel trellis frame”

just one man’s opinion (which he is of course entitled to), though he’s only won a SINGLE title with a half-frame design. why not more…? who knows, maybe casey simply couldn’t get on with steel…? much the same way vale NOW can’t get on with carbon…? guess it all evens out.

but don’t stop there, we should probably seek the opinion of 7 others. especially those who HAVE won multiple titles. 4 have won 2, 1 has won 3, and 2 who have won a whopping 4 each. that’s 13 repeat titles all bagged with the supposedly inferior performance of steel tubing welded together. where some point and say “inconsistent”, a simple review of history shows nothing but “CONSISTENT CHAMPIONSHIPS”…!? the stats are overwhelmingly positive.

just imagine if a compliant steel trellis had been wrapped around a 500 2-stroke engine that was competitive with the NSR’s V4…? honda’s grandprix history might look very different than it does today.

Report this comment