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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 10:12 am 
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Location: Geeeelong! / YURP
jooo, never siad there was an issue with Crumpton. I'd love one, just not sure they float his boat. He was too excited when I mentioned them :(

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 10:25 am 
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Posts: 231
If it was my money it would be going down on a Strong. But if a Crumpton doesn't float his boat I doubt the Strong would either.

The IF Corvid is too ornate for my tastes but has a similarly stellar reputation (to the above) from those whose opinions I value. Probably too heavy for consideration in these parts.


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 Post subject: Re: Lightest Frame
Posted: Mon Oct 01, 2012 10:25 am 


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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 11:07 am 
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Posts: 534
Location: Insjön, SWEDEN
There´s some main differences here.

Monocoque OR tube to tube (commonly called tube to lug).

Tube to tube construction is easily done with small investment.

1. Buy or make tubes.
2. Buy or make lugs.
3. Glue them together
4. If neccessary add carbon weave on joints and critical areas.
5. Sand it, paint it.
6. Sell it.

Monocoque.
BIG investment for molds often in 2 or more parts, separate molds for each size, some manufacturers take shortcuts here and making moulds for headtube and then seat and toptube and lower half of seat tube and downtube maybe chainstays.

1. Make moulds.
2. Buy carbonfiber (prepregged to your spec).
3. Read layup howto for each customers needs.
4. Do it in one pass.
5. Put in oven and then make minor finish adjustements for parts, glue them together.
6. Sell it.

Monocoque is in my eyes a perfect solution IF and only IF it was done for a big part of frame not making shortcuts and do universal fitting.

I walked around in Eurobike and could see raw and cutted up frames in flesh, not impressed of the finish when comparing to the price tag.

In this case Rolo has succeeded, why?

I assume they use a front triangle mould, a chainstay mould and last a seatstay mould.

Three big parts, easily replacable if you crash or damage the frame, BUT in same time you can get a finetuned frame due to different layup, as there´s possibility with different layup, adding and subracting carbon fiber for a desired performance.


With that said, in a tube to tube frame you are not free to make such options, as the tubes are PREmade, or bought in bigger volumes to your spec or standard, not economically good to have a lot of detailed tube spec in stock, only a very few can do it.
You all know whose they are and they are so good, no namedropping here.

If a specialist frame maker would do the tubes from prepreg weave rolls ground up to a finished frame, what would it cost?
Seriously?, in my eyes very time consuming work with too small profit in this business.

For me as amateur carbon butcher it would be a lot of workhours invested then I need to have a competitive pricing quotes too.


Main flaws with lugged frames or separate part monocoque frames is:

Lugs arent flexible as fillet brazed steel joints.
Too big difference in degrees for example 50 cm frame to 56 cm frame gives visible holes in lugs.
Solutions:
1. Separate lugs for each frame size or 2 sizes = expensive.
2. Moving over to no lug construction = time consuming.

Monocoque universal frame parts:
Main flaw with them like GURU and many other that boasting about full monocoque frame construction yada yada.
1. Separate moulds for lower parts of seat tube and BB and headtube.
2. Separate mould for headtube and front toptube, of course upper part of downtube.
3. Upper seat tube and rear toptube.
4. Chainstay and seatstay mould.

Pro: swap out a mould to a smaller or bigger: another size.
Faster production, all layup is same for this specific mould.
One big investment, better payoff.

Con: stack and reach not consistent and flexibility/stiffness ratio is not consistent for each frame size, small is rock solid, bigger is flexy.
BIG glue joints give a unpredictable manner for this tube, what´s the point with expensive good carbon fiber when you splash on 30% of this surface area with glue that have stiffness numbers 1/10 or worser of your $$$ prepreg roll of carbonfiber when you are gluing together the frame for a random customer.


Hope I made it readable from my view of things.
I have no university exam so don´t take my words as truth.
My view is based by EXPERIENCE with making these things for living.

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 2:41 pm 
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Posts: 7404
Location: San Francisco, CA
The big issue with ultra-light frames now is the difference to production frames is so small, the latter more optimized then they used to be, the cutting-edge frames not much lighter since they've long been hitting up against the limits of materials and UCI-sanctioned frame design.

I've been running a lot lately and on a recent run I weighed myself before and after, having drunk or eaten nothing. 11,3 km run = 800 grams lost in sweat, not counting sweat saturating my clothes. So if you invest $3000 to save 150 grams on your frame, that's similar to 2.1 km of running, or around 10 min at the pace I was running that day. So you're investing $3000 to have the bike be as fast now as the old bike would have been in 10 minutes on a warm day (assuming you don;t fill your bottles during that time).

Not that these super-light frames aren't very cool.

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 3:49 pm 
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Joined: Fri Sep 23, 2005 6:34 pm
Posts: 534
Location: Insjön, SWEDEN
djconnel:
You mean the lighter weight from last model is not neccessary for the main evolution?

I see a clear trend here.

Lighter AND better performing frames at LOWER price.

Yes!, the pricing has gone down technology wise as the state of art technology has dripped down to cheaper models all the time, look at any performance industry.

I want my Cannondale SuperSix Himod be a better frame next year, painting does not matter so much but with the same chararestics the weight WILL go DOWN not up!.

Carbon fiber as material have nearly endless limitations, the real limitation is how we use it, you can easily tie up a loose 3K carbon fiber group of strands and hang it all the day with your weight and possibly all your family in a sack if needed to, it´s the resin and manufacturing process that have many tradeoffs nowadays.

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 3:54 pm 
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Joined: Thu Oct 23, 2003 5:18 pm
Posts: 724
Location: Austin
With all due respect, you have it wrong on what I do in "'tube-to-tube" construction.

My tubes are made for me per order, in the US, material(pre-preg), laminate is unique in each tube. My investment in stay molds is also unique to my brand, my design and was also expensive. My joints are wrapped with very high quality UD prepreg sourced in the US with the same resin system as the tubes. My joints are meticulously laid by me and only me. OOAC Vacuum bag cure with assisted pressure distribution in a process outlined in 3 US patents pending(unpublished). The results speak for themselves.

I am sure you have seen many "tube-to-tube" processes and see low quality and low technical processes but I assure you not all are created equal just as in your world of bladder molded monocoques.

You can take a queue from the picture here. Right out of the oven. No sanding needed, only the texture of the "peel ply". Only need to file off the flash just as in your molding. This joint was layed in one shot with no secondary cosmetic layer after sanding(like so many). This is a well consolidated void free laminate co-molded to the tube junction. In all of my destructive testing I have never been able to create and instance of cohesive or adhesive failure between the substrate and wrap. Load to failure always is drawn far from the joint and generally takes dynamic loads of well over 1200lbs to failure in a front impact on my typical 900g frame. If you know bike engineering, you know this is a very excellent.

My question for you is "weave" throughout the laminate?? This is not so good IMO. And given the weight of your frames, I worry about interlaminar sheer between layers of woven fabric as well as the overall lower tensile strength of crimped woven broad goods in the laminates I see in the posts. Can you address this? They do not look like spread tows. Why no UD in there?

Regards,
Nick

Image

Mattias Hellöre wrote:
There´s some main differences here.woven

Monocoque OR tube to tube (commonly called tube to lug).

Tube to tube construction is easily done with small investment.

1. Buy or make tubes.
2. Buy or make lugs.
3. Glue them together
4. If neccessary add carbon weave on joints and critical areas.
5. Sand it, paint it.
6. Sell it.

Monocoque.
BIG investment for molds often in 2 or more parts, separate molds for each size, some manufacturers take shortcuts here and making moulds for headtube and then seat and toptube and lower half of seat tube and downtube maybe chainstays.

1. Make moulds.
2. Buy carbonfiber (prepregged to your spec).
3. Read layup howto for each customers needs.
4. Do it in one pass.
5. Put in oven and then make minor finish adjustements for parts, glue them together.
6. Sell it.

Monocoque is in my eyes a perfect solution IF and only IF it was done for a big part of frame not making shortcuts and do universal fitting.

I walked around in Eurobike and could see raw and cutted up frames in flesh, not impressed of the finish when comparing to the price tag.

In this case Rolo has succeeded, why?

I assume they use a front triangle mould, a chainstay mould and last a seatstay mould.

Three big parts, easily replacable if you crash or damage the frame, BUT in same time you can get a finetuned frame due to different layup, as there´s possibility with different layup, adding and subracting carbon fiber for a desired performance.


With that said, in a tube to tube frame you are not free to make such options, as the tubes are PREmade, or bought in bigger volumes to your spec or standard, not economically good to have a lot of detailed tube spec in stock, only a very few can do it.
You all know whose they are and they are so good, no namedropping here.

If a specialist frame maker would do the tubes from prepreg weave rolls ground up to a finished frame, what would it cost?
Seriously?, in my eyes very time consuming work with too small profit in this business.

For me as amateur carbon butcher it would be a lot of workhours invested then I need to have a competitive pricing quotes too.


Main flaws with lugged frames or separate part monocoque frames is:

Lugs arent flexible as fillet brazed steel joints.
Too big difference in degrees for example 50 cm frame to 56 cm frame gives visible holes in lugs.
Solutions:
1. Separate lugs for each frame size or 2 sizes = expensive.
2. Moving over to no lug construction = time consuming.

Monocoque universal frame parts:
Main flaw with them like GURU and many other that boasting about full monocoque frame construction yada yada.
1. Separate moulds for lower parts of seat tube and BB and headtube.
2. Separate mould for headtube and front toptube, of course upper part of downtube.
3. Upper seat tube and rear toptube.
4. Chainstay and seatstay mould.

Pro: swap out a mould to a smaller or bigger: another size.
Faster production, all layup is same for this specific mould.
One big investment, better payoff.

Con: stack and reach not consistent and flexibility/stiffness ratio is not consistent for each frame size, small is rock solid, bigger is flexy.
BIG glue joints give a unpredictable manner for this tube, what´s the point with expensive good carbon fiber when you splash on 30% of this surface area with glue that have stiffness numbers 1/10 or worser of your $$$ prepreg roll of carbonfiber when you are gluing together the frame for a random customer.


Hope I made it readable from my view of things.
I have no university exam so don´t take my words as truth.
My view is based by EXPERIENCE with making these things for living.

_________________
www.crumptoncycles.com


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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 3:55 pm 
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Posts: 724
Location: Austin
ps, I am also not limited to shape or size. No small, med and large here.

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 4:09 pm 
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Joined: Fri Sep 23, 2005 6:34 pm
Posts: 534
Location: Insjön, SWEDEN
nicrump: good you chimed in here, as I mentioned in very end in my post, my experience has shown me what I seen in good and bad ways.

You and a few others are doing that from ground up and can make it in large quantities which keeps it all more economical.
Regarding in depth details of Rolo, I´m not a part of the team who builds them so I cannot answer your question, in general they do a good stuff which Zedler has shown.

I need to know how you can KNOW the frames ride quality when you use a large amount of the surface area in the ends in glue surface on the lugs.

Let us assume there´s a new glue type which is 30% stronger than your present, will the frame ride 30% stronger or what?

A another question, if you specialordered the tubes for you, are they up and down dependent, i.e twist the tube 90 degrees will you get a different ride feel?

I was more speaking about how Guru and Colnago make their frame in general and they are not unique, many others use the very same technique, I can maybe write down more than 10 companies of each type, some of them do blend tube to tube and monocoque type manufacturing process.

A last one thing, if I want a 600 gram frame, how do you do it?
Make new lugs and tubes from prepreg or do you reuse your lugs?

These in depth details is exciting for me to know and share.

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 4:32 pm 
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Joined: Wed Sep 26, 2007 1:57 pm
Posts: 7404
Location: San Francisco, CA
This is consistent with my point that the production frames have gotten lighter faster than the ultra-light frames. The ultra-lights are more expensive then they were previously, while the mid-range carbon frames at the same weight, are cheaper. So the weight gap has fallen.

I can't comment on ride quality: I've not ridden enough bikes. My Fuji SL1 from 2008 rides quite nicely. Personally I think stiffness numbers are over-rated for any but the most powerful riders competing in events where instantaneous power is critical. But I don't contest carbon production frames ride better than they used to.

Mattias Hellöre wrote:
djconnel:
You mean the lighter weight from last model is not neccessary for the main evolution?

I see a clear trend here.

Lighter AND better performing frames at LOWER price.

_________________
http://djconnel.blogspot.com/
Fuji SL/1
\


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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 4:52 pm 
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Joined: Sun Dec 16, 2007 9:33 pm
Posts: 713
Location: Luxembourg / Sweden
Don't want this to turn into another this versus that discussion.

We are a very, very small startup company and obviously Nick Crumpton has a vast experience in the field.
We have of course nothing but the utmost respect for him, Bob Parlee or for that matter my friend Marc at SPIN, all builders of
top tube to tube bikes.

I count myself fortunate to own both a SPIN and a Parlee Z1, maybe one day if we are successful I will be able to buy a Crumpton...
We chose to do things differently because we feel it is the best way to go about constructing bicycle frames in carbon, thats all.
Nick does it his way, Bob does it his and Marc does it his. It all comes down to what customer chooses, I hope there is room for us to
all live and prosper.
We feel we do the very best frames and so does all these other guys, and rightly so!

One of the best things about the bicycle industry is the warm reception we've had by people that are veterans and legends in the industry,
guys like Marcus Storck, Gerhard Vroomen, Heinz Obermayer all took time to come over to our little booth at Eurobike to wish us welcome to the industry.
Really sweet and heartwarming for a bunch of middle aged guys trying something new, we would like to keep it that way!

Best,

/a

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 Post subject: Re: Lightest Frame
PostPosted: Mon Oct 01, 2012 5:17 pm 
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Joined: Sun Dec 16, 2007 9:33 pm
Posts: 713
Location: Luxembourg / Sweden
Reading through Nicks post again I want to make sure there is no misunderstanding. We make our frames in our small facility in Linköping Sweden.
We have engaged Mattias (Experimental Prototype a separate company ) to manufacture prototype parts at his facility 500km away from Linköping.
While he does not speak for us he has been extremely helpful in producing top quality parts like drop outs for us, sometimes under crazy time constraints.
He does not make our frames and he is not intimately familiar with the process.

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 Post subject: Re: Lightest Frame
PostPosted: Tue Oct 02, 2012 1:32 pm 
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Joined: Wed Sep 26, 2007 1:57 pm
Posts: 7404
Location: San Francisco, CA
andy2 wrote:
I count myself fortunate to own both a SPIN and a Parlee Z1, maybe one day if we are successful I will be able to buy a Crumpton...
We feel we do the very best frames and so does all these other guys, and rightly so!

/a


Okay -- I get a SPIN, Z0, Crumpton, one of your impressive frames, and I still have my 2008 Fuji SL/1. I put the same components and parts on all of them. I weigh 57 kg. I have custom geometry on the customs, but the contact points are the same. Maybe the trail's a bit long on the Fuji, but I can deal with that, and for some descents it's even nice. The Fuji's 860 grams frame + 360 grams fork but the others are 720 + 310. The difference is the same as the difference whether my bottle is full or half full. I weigh 57 kg, so the weight difference total is less than 0.2%, no more than 6 seconds per hour of steep climbing. I can sustain maybe 350 watts over short climbs, so I don't flex the Fuji in any noticeable fashion, especially with its small main triangle.

Am I glad I got these high-end frames?

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 Post subject: Re: Lightest Frame
PostPosted: Tue Oct 02, 2012 1:46 pm 
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Location: Canada
Come on DJ, where did you scientific approach go ?

Don't let arbitrary, affective stuff like dough get in the way of the ONLY thing that really counts: Numbers (and weight :twisted: ) !!!! :wink:

Louis :)


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 Post subject: Re: Lightest Frame
PostPosted: Tue Oct 02, 2012 2:37 pm 
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It's not all in the no:s DJ!
We will have a bike for you in Palo Alto in about a week. PM me and you can haveit for a couple of days, see if we can change your mind! :?
/a

PS Our frame is 640 + 240 btwy, don't lump us up with those portly 720+310's! :mrgreen: .. Happy you're so in love with your bike though! DS

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 Post subject: Re: Lightest Frame
PostPosted: Wed Oct 03, 2012 12:37 am 
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Location: San Francisco, CA
andy2 wrote:
We will have a bike for you in Palo Alto in about a week. PM me and you can haveit for a couple of days, see if we can change your mind! :?
/a

PS Our frame is 640 + 240 btwy, don't lump us up with those portly 720+310's! :mrgreen: .. Happy you're so in love with your bike though! DS


:shock:

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 Post subject: Re: Lightest Frame
Posted: Wed Oct 03, 2012 12:37 am 


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