Carbon Frames - How light is too light !

pipsqueak

Just seen Ribble advertising the Scuro carbon frame at 870 grammes !!!
Is this too light ? Is their such a thing as too light ?
I figure their must be a point at which the strength and longevitiy of these frames at this weight, is seriously compromised.
Or is this not the case, Does new technology and carbon frame making techniques ensure that the weight will constantly reduce.
I was told by bloke at Ribble that its all in the weave, and that they are extremely strong.
I know "sweet fanny adams" about frame building but am intereted in buying a new carbon frame. and am just concerned that this frame is just ...too light.

Any advice / veiws appreciated.
Thanks.

Kléber

Cervelo and Scott both make frames at the same weight, in fact they subcontract the manufacture of their frames to the same Chinese company.

Ribble isn't a frame designer or builder, this will just be a generic frame with some Ribble stickers on it. I don't know the frame but it's possible that it's a sloping frame in size XS that weighs 870g? The Scott Addict and CR-1, along with the Cervelo R3 are all great frames with excellent reviews and lifetime warranties. They are all some of the stiffest frames you can get, the R3 is incredibly stiff in the BB area for a sub-1kg frame.

In other words, an 850g frame is fine. Of course, it has its limits, if you crash it or drop a large spanner on it, expect problems. That said, Scott make the Scale MTB with the same thin tubing as the Addict and that's fine for offroad thrills and spills.

andylav

These frames are made by Dedacciai and resold as Ciocc, Bottechia, Kona, Ribble and Condor branded items

I have a medium frame and it weighs 957 grammes.

Being returned for exchange for a large as there is no layback on the seatpost - something to be aware of when considering top tube length and your normal reach

I'm expecting the large will be 1000 - 1050 grammes, which is similar to my Giant TCR frame, but hopefully the Scuro will be stiffer, particularly around the bottom bracket

passout

It's fine - unless it breaks in which case it isn't.

aracer

andylav wrote:

there is no layback on the seatpost

Glad I didn't go for one of those then - it's a custom post so nothing else will fit in one of those? I like to sit well back, so no frame size would fit me. Just ordered one of http://pedalforce.com/online/product_in ... cts_id=348 instead - 1050g in 55cm (equivalent to a large in Scurro sizing) but a lot cheaper!

Plenty of <900g frames around in normal sizes, and most of them don't break. They're just generally rather expensive - the technology involved to make something that light and still strong costs money.

677.5g for a frame is too light (though not as bad as some of the other stuff on this bike)!
http://weightweenies.starbike.com/phpBB ... b03b291139

Down the Road

Light Strong Cheap PICK 2

simple philosophy but it always works. There are some rules of engineering that cannot be altered.

Remember SCOTT insist you return the frame to them every year for inspection at your cost.

bryanm

Don't forget the ballast for these supadupa light bikes if you want to be UCI legal!

aracer

I don't think anybody posting here has to actually worry about the UCI commisaires declaring their bike too light.

Meanwhile that much abused KB quote has to be kept in context - see http://www.cyclingnews.com/tech.php?id= ... /bontrager for his comments on it. It's an engineering trade-off, but you have to bear in mind that light and strong tends to get cheaper every year and also that expensive and light may not be any stronger than cheap and light - you may just be paying for a brand name and/or increased distribution layers (see other threads on here).

Monty Dog

It's well within the bounds of modern materials technologies to make a frame that's light and strong enough, the difficultly typically comes to make the process repeatable enough to make sure every one is consistent. There's also the question of durability, because increased resin content makes the materials tougher, but heavier. There's probably an argument to say that the greater volume in production, then the more likelihood of a composite frame being better made as it is more process dependent than say a welded frame, which is more reliant upon operator skill. If you read some of the articles about Aerogel recently, I expect we'll see sub-500g frames at some stage and we'll all be laughing at those 900g 'lumps that we used to ride years ago. By all means, buy one of these 'flyweights' but don't expect to jump back on it if you crash.

aracer

Monty Dog wrote:

increased resin content makes the materials tougher

Not convinced by that - the resin surely does nothing more than holds the fibres in the right place. If you want tougher that does mean heavier, but due to more fibres (or potentially different fibres), not more resin.

socrates

Question for Down the Road - Is that all Scott road frames or just the Addict

andylav

Scott rule -BLIMEY

Been considering one of their frames for a while now and had been tempted by a few offerings on Ebay but was hesitant because of the lack of a replaceable hangar. Now that some of the frames have this functionality, I'd started to consider one again but glad I didn't do anything as I'd never heard of this requirement (to maintain warranty presumably ?)

Down the Road

Just the addict But then we are discussing low weight frames.

sevenofeleven

Was in LBS this week and got round to talking bout the Scott Addict on display and was told Scott are now working on 500g frame this winter!! as predicted by Monty Dog in his crystal ball! "pea and ham from a chicken! now that is clever!!!"