Aluminum frames
 

I have a quick question, is there a weight capacity for aluminum frames, and a aluminum frames generally stronger than carbon??

Frames don't hold your weight, the wheels do.

Well i just purchased a caad9-6 with the shimano wh-500 wheelset, I am 6,2 240 lbs, am i gonna f@!#ck the things up cause of my weight??

I would say you will be fine. Cannondale makes some of the stiffest and strongest frames in my opinion. Also if you purchased the bike through a bike shop and they did not make you upgrade the wheels, etc. then you should be good. I hope this helps.

The frame won't be a problem. The wheels might, but not right away, ride them and have them trued and tensioned after a couple hundred miles.

Thats the plan, i am going to ride the wheelset and the compenents into the ground, then upgrade...

The material itself won't be an issue; the bike designs may vary. I mean, bike designers could take any material and make a frame as strong or as weak as they wanted to.

I'm 260lbs and have an alu bike for the first time and feel like I'm gonna snap it, i don't feel comfortable riding it at all so it's up to the rider too. I'm gonna shed some weight before I go on it cos its such a lovely bike I don't want to break it! i've always had steel bikes, they feel better to me. just my 2 cents

Aluminum will serve you well for years. You have the right idea. Ride that baby untill the miles wear her compnenets and wheels down and then go an upgrade spree. Of course, just replacing things as they wear out works too.

BTW, as they say in the Roadie forum, "This thread is useless withought pics!"

I undertand being concerned and not wanting to hurt a new bike. They are kind of like our kids, lol.

You will be fine though. Bikes are meant to be ridden, so just ride.

I'm 270lbs and ride an aluminum CAAD9. I can sprint, stand up on hills, go for hours without any feeling of flex or weakness. If for some reason something happens, Cdale warranties their frames.

The wheels are the weakest part, and like everyone has said. Ride it a few hundred miles and have the rims trued by someone that knows what they are doing. I have over 5000 miles on my aluminum frame and wheel set. A few broken spokes in the beginning, because they needed to be trued and proper torque to even and minimal problems since.


Good luck and pictures would be good.

Most decent frames, fall into 2 categories, normal frames, which tend to be designed extra strong. Normal frames have been ridden by folks north of 180kg (~400lbs), and most have no strict limit. There are also super light frames which are designed to be as light as possible, in todays litigious society these will always have a published weight limit, typically around 80kg (~175lbs)

Not sure which is stronger, AL or Carbon fibre reinforced plastic (CF). CF is made in a similar manner to fibreglass, the carbon fibre itself is a thread which is a continuous chain of carbon molecules, this chain is then woven into a cloth. This cloth is then coated with a plastic resin in layers, to build up the actual material. Part of the issue with strength is every cloth has a bias or grain, and is generally stronger in one direction then the other. This means for the strongest material alternates the grain direction, just like plywood is made by alternating the grain in layers of wood. Problem with CF in doing this is that you need to cut the cloth to fit, and cutting each layer in a different direction can lead to wasted material, and the CF cloth is very expensive. This is less of an issue with factory frames where they turn out dozens or hundreds of identical frames every day.

To sum up, a frame that does not have a weight limit, is generally suitable for a rider of any weight, where as a frame or bicycle that has a weight limit, should generally have that limit respected. Mind you a lot of riders who are a few kilos over that limit are generally okay.

Thanks for the info guys. I ordered the bike a couple of days ago, and when it arrives i will show some pics...

Then check with Shimano about the weight limitation on that wheelset. The shop you ordered it from should know.

Carbon fiber *sounds* flimsy ... but we build fighter jets from aluminum and CF... Manufacturers design their products taking into account product weight, cost and load/performance ranges they wish to meet.

I ride a women's CF bike and as an Athena/Clyde girl I am sure I weigh more than their typical dainty 125-lb rider. I also commute with this bike so I put another 15# on it with a seatpost rack/pannier. So far I have 1500 miles on this bike and I believe I just have a little more wear on the rear tire than usual. However, I am careful to get up off the saddle on bumpy road surfaces, avoid potholes, and otherwise try to treat the bike nicely. I did swap out the CF seatpost for alloy just because it was not designed for the type of forces a beam rack places on it.

I'm 220 lbs and have been riding my featherweight alu Kona ***** bike frame for ten years without issue... I went through a period of broken spokes, after which I changed to Continental Gatorskin tires. Problem solved.

I have no business being on a sub-20 lb bike like my Kona, but it still likes me.

Well here it is, my caad9 6. Im loving it.http://www.bikeforums.net/attachment...2&d=1242269981

Beautiful bike, not sure if you saw mine in the roadie forum.

http://i162.photobucket.com/albums/t...m/IMG_7625.jpg

We also build race cars and use use carbon fiber in lots of applications where lightweight and high stress meet. However this is not exactly and apples to apples comparison in this case. The biggest concern with carbon fiber is not if it can withstand the weight of a clyde (most can), but rather when it will fail. Carbon Fiber frames tend to go snappy snappy when they fail with next to no warning whatsoever. Aluminum can crack a little bit before failing, steel can be in much worse shape and still be ridable.

*Whistles a cat call at the shiney new CADD 9* nice bike!

Ya i saw it, thats a rival crank you have on there right, the your bike looks nice. I am going to upgrade to rival, and throw all my tiagra, on an old steel frame that i have.

Yeah rival crank, it works well with the Tiagra. I'm gonna upgrade to Rival soon though. I'm ordering a pair of Neuvation wheels when i get back from vacation. I've been ebaying stuff and the first thing to swap are the wheels. The swap will take about a lb off the bike. The rival is just the best bang for the buck groupset on the market. I'm also gonna swap out the stem and bars with 3T ergosum bars and a shorter 90mm stem.

Yeah, carbon fiber could just suddenly fail at literally any time. Keep some water handy to cool it on long descents, or else BOOM.
:rolleyes:

Hendrick, grats on the C'dale! Ride the snot out of that wheelset! I'm a couple lbs short of 250 and have that wheelset on one of my bikes. They have been true and trouble free for many miles. I'm also building up an aluminum framed fixie/single speed to train on, and I'm picking up my new carbon frame and fork that will be the center of my next build on Tues.! Bottom line: Don't fear the material. If the gov't and all of it's little entities haven't cleared a material as safe, then it probably isnt. Good luck and enjoy!

Carbon Fibre Reinforced plastic frames do not simply collapse, what happens is that the carbon fibres get damaged, usually in some kind of crash, which weakens the material. Not much research has been done yet on repairing it, so bicycle manufacturers tend to replace. Steel has been around for Millennia so repairing it is common, even AL can be repaired with the right materials and equipment and so can Ti.