# Could I be too HEAVY for an older Look frame?



## emoney (May 9, 2009)

Ok, I'm new to the whole cycling community, and have recently purchased and built an older Look KG121. Here's my question;

Can a person be too heavy to ride an older carbon bike?

The reason I ask is because of a "they said" thing. I had a guy I ride with who told me a horror story about a guy my size, <6'2", 225lbs> riding an older KG96 and the carbon tubes separated from the lugs. I'm not even real sure what that means, but is this a concern for real, or just another horror story? 
If I am too heavy, which I'm working on btw, is there a way to know if the lugs/tubes are stressed on my bike now? If there's a problem, what's a person to do? Do regular LBSs repair carbon bikes like this (I know I can just call them) and if not, is there a specific place that people go to have them repaired?
I'm one of those ounce of prevention, pound of cure people and if there's even a remote concern, I'd rather have someone who knows what they're doing make sure I don't have a problem and correct it before I'm riding 20mph around a sharp bend and the bike wipes me out.
Thanks for any and all help


----------



## dmar836 (Nov 17, 2007)

My only experience is with the Trek 2200/2300s of the early 90's. They can flex under load as the technology wasn't as developed. In other words they used carbon tubes in the same way as they would have used steel tubes. You'll notice there is an entirely different appearance to the bottom bracket and head tube areas of a modern carbon bike.
My father in law T-boned a Mercedes on a 2300 and he showed me a carbon tube(actually aluminum wrapped in carbon) that had separated from the lug cleanly. 
I sold my 2200 as there were small areas of delamination. I still trusted it but it would shift on occasion when I would hammer up a steep grade(>10%) and I'm only 160-165 lbs.

As far as repair, there is unlikely to be a local shop that is able or willing to repair carbon, much less on a vintage bike. Besides, it's the joints b/w the carbon tubes and the aluminum lugs that would likely be your issue - and that's sort of a subspecialty.
Look might offer that service so I would give them a call. There are specialists that can repair modern carbon bikes. Sorry I can't offer you more info. 
Dave
KC


----------



## old'n'slow (Sep 4, 2007)

For whatever it's worth - I'm a larger guy (approx. 230 lbs.) currently riding a Look 381i (it's either an '03 or '04, I'm uncertain). I've had the frame since late last year and put a little over 2000 miles on it without a single issue. 

My version has material that smooths the transition between the lugs and carbon fiber tubes. I've read about cracks forming near the transition area, but so far, so good. 

My other bike is a titanium Serotta and quite frankly, I'm not sure I could choose which one I'd part with if I had to make a choice. Luckily, I don't have to...


----------



## dmar836 (Nov 17, 2007)

I purchased an old KG76 on Ebay. I'll let you know how flexy it is compared to my Trek once I receive it.
I have read that most failures on these bikes are not catastrophic as a tube might come unglued but not likely come completely out of the lug. If my Trek was any indication, you should quickly feel such a change strange handling and/or ghost shifting.
Dave
KC


----------

