MotoGP Forum  

Go Back   MotoGP Forum > MotoGP Forum > MotoGP

MotoGP MotoGP Forum - MotoGP Class Motorcycle Racing Forum


Reply
 
LinkBack Thread Tools Display Modes
September 19th, 2011, 12:57 AM   #21
Senior Member
 
Joined: Oct 2010
From: Vancouver

Posts: 1,187
Likes: 8

Quote:
Originally Posted by birdman View Post
Well it was actually in downhill mountain bike that I was looking at buying CF. Its made to take big hits, and yes that includes scratches. They have to be reliable and durable, and it is a potential legal minefield because a frame failure in downhill equates to a broken neck, so no cycle manufacturer can afford to go through that.



A carbon cycle frame was once $20k or more, now its down to $3k and used by many companies much smaller than Ducati. Therefore the future as I see it would be a CF Ducati 1198 that weighs in a good 10kg less, say in the 165kg range. If they cant achieve that no use in using carbon.


Well crap. The last time I looked at a CF bike frame it was a street bike, it was about 12k (frame only) and weighed about as much as a peice of paper. But the dude at the store told me (price aside) the drawback was if you take a spill that's it, frame over. I guess they've since crossed that bridge.



The issue as I see it for a MC frame in MotoGP is the frames are constantly being changed and updated and with CF this is a slow expensive proccess. That and Ducati still don't have a design that works, the only time they won a WC was with steel. I get that they tried to steal a march and jump ahead, but it didn't work and they are now well behind.



Like I said before, maybe one day CF is the answer but it's not today IMO. It's still just a good idea on paper, but so was ultra low center of gravity bikes and eight valve,dual con rod, oval cylinders....
bluegreen is offline  
 
September 19th, 2011, 01:58 AM   #22
 
Joined: Nov 2010
From: Somewhere near Málaga

Posts: 49

Quote:
Originally Posted by birdman View Post
It is by far in cycling, as i found out recently. In amateur comp level bikes even the cost is about the same, and my alloy bike is like a coke can, so thin it sounds like a rock will punch a hole right through. CF better.


The problem is when we start throwing around absolutes like 'better'. CF is better for some things, worse for others, and the trade-off for Ducati does not appear to have been worth it. My dad was a club cyclist and two of his good friends were frame-builders with workshops near where I lived, we talked about this a lot and got lots of hands-on examples. If we compare steel, CF and aluminium frames for road racing, they behave and feel so different that eventually you are forced to pick the material that provides the characteristics that you need for the particular competition you're in, then just put up with its disadvantages.



CF is stiff and light, and is perfect for time trial and short-distance track events as far less pedalling energy is lost through frame flex. But it makes for a very unforgiving frame. That is why if you follow the Tour de France they use CF frames for the time trial stages but not for longer days, even in the mountains where their advantages would be put to good use. If you ride a CF bike for long days at high speed it quickly becomes unbearable. Of course if for an amateur rider with more money than sense who never rides long distances at high speed but has to have 'the best', it is an ideal material.



Aluminium frames used to be considered a woeful compromise as the primary benefit, lightness, was balanced out by a curious combination of far less rigidity but quite high apparent rigidity - the frame would flex heaps but due to its snap-back would feel very unforgiving (I remember that on two bikes with nearly identical setups and geometry I always finished feeling more tired and sore on my very nice Vitus ali frame than on my steel frame, and I was no quicker either). This all changed with the advent of oversized tubing, which as you say allows the use of large diameter but paper-thin tubing which is less prone to flex and feels less whippy.



The comfortable choice, and used by many teams up to the mid-90s, was a good carbon steel frame (with manganese and molybdinum) using Reynolds 531 or 753, or an equivalent from Columbus or one of the other tube-makers. Stiff but forgiving, much more comfortable and fun to ride, and not much heavier than alloy frames. I've tried all three, titanium as well, and my main bike is still a hand-made criterium frame made of Columbus SLX.



All that was just to say that I can imagine exactly what the advantages of CF are, and can imagine exactly how its properties can work against the rider. But if we've learned anything from this weekend's results and Rossi's subsequent comments, it is that the inherent problem is not the material but the design. As for Burgess, I'm sure he's doing the best he can with the parts he's given. Same as Nicky's crew. Same as Stoner's crew in previous seasons.
corinthian is offline  
September 19th, 2011, 03:28 AM   #23
Senior Member
 
birdman's Avatar
 
Joined: Jul 2011
From: Dont Know

Posts: 1,404
Likes: 813

Damn. Bluegreen and Corinthian called my bluff on CF. Truth is I know little about it, but now thanks to your info I know more.



This was what I was looking at:



"IMP™ – Integrated Molding Process

Our engineers have developed IMP™, the newest technology applied to carbon production. The top tube, head tube and down tube are produced in a single step using a top-secret process. Our proprietary process allows for lighter construction by removing 11% of the material from the head tube intersection while increasing strength by utilizing high modulus HMF composite fibre, now in combination with our brand new HMX composite fibre. IMP™ also increases strength by utilizing high modulus stressed fibers with more precise fiber placement in critical areas. The result of this exclusive combination is a truly unique stiffness/weight ratio. Complimenting the IMP process, our frames benefit from our Naked External Tube set (NET™) finish, which eliminates the cosmetic carbon layer to shave precious grams."







Ok ok its better than what I would ever need, but shit I'm turning 37 and unlike my wife dont believe in re-incarnation, so i said to hell with it, I want it now. But I didnt buy this. I got a Giant Reign 0 made from 6061 alloy I believe. To those wondering if it makes much difference, compared to my old $1k bike, this Giant is so good its not funny. With my limited skills I can do gnarly downhill runs with no brakes and almost float over the terain. Its an orgasmic feeling. Whoops running to the bathroom...................................



Ok I'm back. Did some CF research. In the early days it was a difficult material to get right and very expensive. Now days it seams they can make CF mirror any material you want (with flex) with a high weight advantage. For example tour de France. Looking at the bikes you would never know what is CF because they make it look the same. http://www.bikecycli...com/frames.html





Thats apparently a CF frame joined by lugs.



The cycle progression has been steel to alluminium to CF.



So I get where Ducati were heading. A long time ago sports bikes had steel frames. They sucked and were replaced with alloy delta box. Ducati tried to skip alloy and go straight to CF. After all CF has come a long way. They were very, very close. Stoner went pretty good with it, won races.



With my limited engineering understanding, in mechanical terms Stoner found a way to make the CF Ducati work. So in outright grip it works. Feel? Well someday all riders may equate CF to the best "feel" but that day may still be a ways off.
birdman is offline  
September 19th, 2011, 03:49 AM   #24
Senior Member
 
Joined: Jun 2007
From: Norah Head

Posts: 9,436
Likes: 978

I Ride: Many
CF is great for fishing rods! ( Rog. knows this because I told him so )



CF is crap for violins.



CF is crap for bike mufflers





Oh and No JB is not trying to get fired, he's trying to get Ducati "fired up".
BarryMachine is offline  
September 19th, 2011, 04:27 AM   #25
 
Joined: Jul 2007

Posts: 545

Quote:
Originally Posted by birdman View Post
Well it was actually in downhill mountain bike that I was looking at buying CF. Its made to take big hits, and yes that includes scratches. They have to be reliable and durable, and it is a potential legal minefield because a frame failure in downhill equates to a broken neck, so no cycle manufacturer can afford to go through that.



A carbon cycle frame was once $20k or more, now its down to $3k and used by many companies much smaller than Ducati. Therefore the future as I see it would be a CF Ducati 1198 that weighs in a good 10kg less, say in the 165kg range. If they cant achieve that no use in using carbon.


I dont think you can compare the use of CF on a downhill bike to that of a motorcycle. A DH bike made from CF has to be stiff and light, thats about it. CF used on a motorcycle needs to flex and thats where the problems are occuring.



Where do you ride btw? Do you race?
spooky is offline  
September 19th, 2011, 04:54 AM   #26
Tom
Senior Member
 
Joined: Feb 2006
From: West Yorkshire, UK

Posts: 9,351

I don't think JB is trying to get fired but it seems that the whole crew, and even the eternally patient Nicky Hayden are getting fed up with that lack of progress with the bike. Obviously these things take time, but i think the Rossi side of the garage at least have called for a conventional twin spar chassis and are probably frustrated with the stop gaps and half way houses between Ducati's innovative ideas and what they feel is the simple, and most productive solution. This year has been the worst possible nightmare and it must be worrying for everyone, things need to get a whole lot better next year.
Tom is offline  
September 19th, 2011, 05:11 AM   #27
Senior Member
 
birdman's Avatar
 
Joined: Jul 2011
From: Dont Know

Posts: 1,404
Likes: 813

Quote:
Originally Posted by spooky View Post
I dont think you can compare the use of CF on a downhill bike to that of a motorcycle. A DH bike made from CF has to be stiff and light, thats about it. CF used on a motorcycle needs to flex and thats where the problems are occuring.



Where do you ride btw? Do you race?
Just comparing the way materials have generally progressed: steel -> alluminium -> CF.



No racing only ride for fun. Never been serious and usually had no money until recently. Riding has been where-ever i lived at the time - Blue Mountains, Wollongong, now ride around at Kemps Creek or Menai (Sydney).
birdman is offline  
September 19th, 2011, 05:13 AM   #28
 
Joined: Nov 2010
From: Somewhere near Málaga

Posts: 49

During his commentary Dennis Noyes said that it's possible Burgess won't be with Ducati next season, in part due to his wife's ongoing treatment for cancer. Today Noyes has posted an interesting rumour: 'Hot paddock rummor centered on Rossi testing "conventional" FTR frame in Jerez this weekend. Lots of catch-up for D this winter'. If this rumour is true then Ducati will need him more than ever as his prior experience with twin-spar frames will no doubt be invaluable.
corinthian is offline  
September 19th, 2011, 05:32 AM   #29
Tom
Senior Member
 
Joined: Feb 2006
From: West Yorkshire, UK

Posts: 9,351

What is Erv Kanemoto doing these days? That'd be a real shame if JB left, for whatever reason
Tom is offline  
September 19th, 2011, 07:22 AM   #30
 
Joined: Jul 2007

Posts: 545

Quote:
Originally Posted by birdman View Post
Just comparing the way materials have generally progressed: steel -> alluminium -> CF.



No racing only ride for fun. Never been serious and usually had no money until recently. Riding has been where-ever i lived at the time - Blue Mountains, Wollongong, now ride around at Kemps Creek or Menai (Sydney).


Cool. I'm not saying carbon wouldnt work but with such a small structure, building flex into it is going to be very hard. A conventional twin spar CF frame may work though...



Nice 1! Been racing DH for years, plenty of good tracks within a couple of hours of Glasgow, Ft Bill is only 2.5hours away...
spooky is offline  
Reply

  MotoGP Forum > MotoGP Forum > MotoGP

Tags
burgess, fired



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
If you don't win the Championship...you're fired. xx CURVE xx MotoGP 32 August 19th, 2006 01:09 AM
burgess frosty58 MotoGP 27 September 27th, 2005 06:16 AM


Facebook Twitter Google+ RSS Feed



Copyright © 2005-2018 Powerslide. All rights reserved.
MotoGP Forum is a MotoGP enthusiast's forum, but it is in no way affiliated with, nor does it represent MotoGP or Dorna Sports, S.L. of Madrid, Spain.