RollCNY

Currently, I ride a flat bar road bike built around an aluminum Nashbar frame. It has been a very nice ride for the $80 I spent on it. At the time, I eyeballed their carbon chainstay / seatstay alum frame, but thought $200 was too big a plunge on screwy looking geometry (the frames are really short and really tall).

Well, last night in the wee hours of the morning I impulse bought the frame, for $120 plus shipping (love it when coupons and sales collide). My sleep deprived brain said that I blow that on family night out to eat and the movies, so go tangible.

So here's the question: in changing frames, of identical geometry and construction, with the carbon rear triangle being the only variable, will I notice any difference? Would "Captain America" and the Olive Garden been a better choice?

wi.flash

I would say weight for sure.

ibis_ti

I doubt you will notice a difference, there is more deflection in the tire than in the stays. Anyway, you're not exactly out $120 as you still have the old frame and can sell it. Also, finding out the difference for yourself is worth some amount of money. Let us know the results.

justkeepedaling

Screw Captain America and Olive Garden XD. Neither are worth as much as a nice bike. I mean, Olive Garden? LOL

Seattle Forrest

Probably a small difference in road buzz.

RollCNY

It's funny in that I really don't expect a perceivable difference, but I had to know. I am not sure if it will weigh less or more, as I have heard opposing claims. I will have to figure out how to weigh it accurately enough to know.

Selling the old frame isn't a bad idea. I thought of stashing it in my shed in case the new one turns out to be frail, and then I could be up and going with no down time.

My biggest hope is that the black chainstays show less drivetrain lube than the current bone white, and are easy to keep clean.

Seattle Forrest

Does the new one have a warranty?

mmmdonuts

I think you'll notice more flex in the rear triangle. Weight difference, if any, won't be noticeable.

RollCNY

Excellent question.. I have no clue. For the money spent, I didn't even think of it.

For those interested, here is my attempt at posting the link:

https://www.nashbar.com/bikes/Product...1_10000_202389

RollCNY

More flex would be bad. Any thoughts on how to measure?

mmmdonuts

At home you could flex it at the rear dropouts (squeeze/spread) to compare the frames. If you have a sturdy trainer mount them and flex at the BB and then the seat cluster. Unless you have a good fixed point it will be hard to get accurate measurements but you should be able to compare how they feel and how much visible movement you can detect.

RollCNY

Okay, the frame arrived, and the parts transferred.

New Build



Old Frame


The results: Old frame with DR hanger, cable guide, water bottle bolts weighed 3.66 lbs. New frame 3.44 lbs. I was surprised the carbon rear frame was lighter. I expected it to be heavier based upon the joints.

Ride results: I hate to say it, but with almost 100 miles on the new frame, the carbon rear feels like it dulls down road noise. I thought it would all be hype, but it definitely feels different. The all aluminum frame would let you feel the texture of the surface you are on, not necessarily in a bad way, but I could "feel" the grain of the road I was on. If I road over seams or cracks, I would feel them crisply. The carbon rear end cuts down on the transmitted feel. I didn't expect it, but I seriously think that it does, on this specific frame design.

Stiffness results: From a power transfer stand point, I don't know yet. My plan is to put it on a Tacx Fortius trainer at the bike shop, and pound it. I have baseline numbers from the all aluminum build, and want to compare. From a road ride standpoint, it feels as stiff. On the frame I road prior to the Nashbar all aluminum, I would feel as if the bike had a flat on hill climbs, and all sorts of things would rub when the frame was stressed. The carbon / alum frame feels identical to the all alum on climbs so far. I was worried that it would be drastically reduced, and it hasn't been.

So on two frames with identical geometry, the carbon rear does change the ride. I honestly didn't think it was. It was definitely worth more than Captain America and the Olive Garden, which was the original question.

RollCNY

And please don't tell me that the pictures show the bike cross-chained. I know that, it was not ridden that way, I had just finished tuning DR's and wanted to make sure chain length was okay as a double check.

CNY James

nice pick up, i've been curious about that frame...

RollCNY

Thanks. There are several threads cooking on this Nashbar frame at the moment, so I thought I would post the conclusion.

Of course, I am still ogling the Felt F4's and 5's, but it really did surprise me how much it changed the rides. And it amazes me that, with shipping, I have 2 frames to play with for $230 total investment.

motobecane69

if you really don't like the geometry go to the bike island website and you can get one of the motobecane aluminum frames with carbon seat stays that have a little more normal geometry (longer top tubes int he larger sizes than the nashbar frames) they are only carbon seat stays tho, the chain stays are still aluminum.

halfspeed

The differences in weight and perceived feel may have more to do with the new one being a just plain better frame than it does specifically with the carbon.

RollCNY

For me, I like the geometry. Others may find it odd, hence my comments about it at times. I broke my collar bone years ago, and my shoulder goes numb if I am too stretched out. So short but tall works in my situation. It may not work for others, so individual results may vary.

RollCNY

Possibly, but both frames have identical geometry, made in the same place, identical welds, so I am assuming all tubing the same except for the rear. I have always believed the carbon rear to be marketing BS, and everyone has said that frame design may make more difference than the materials. This was the closest experiment I could step into with the smallest variable change. Closest to Apples to Apples I could get.

And honestly, my results are totally subjective. As I ride the new build, I keep asking myself if it really feels smoother, or do I just think it is. Every situation that I can force, it feels smoother. I pick coarse chip seal routes that I have a clear mental image of the ride on the all alum frame, and the feeling is different. But darn I want objective data.

hyhuu

FWIW, of the two bikes I have, one is all aluminum and the other has a carbon seat stay. The latter one ride much smoother than the first. It's highly noticeable after 50 miles on the saddle. However, it's difficult to compare because they are different brand with slightly different geometry. But one thing I can tell is the carbon seat stay is more flexible when I squeezed it compared to the aluminum one.

Syncmaster

Looks sweet! I posted the build I did on the same frame a little while ago. I am absolutely loving my nashbar frame as well. Couldn't be happier! At $150 it's really a steal. I see you got it for even less! Wish I'd gotten in on that coupon code....

justkeepedaling

I may be picking one up, so I'm wondering if anyone's tried a Rocky Mountain Solo AC:70. Columbus Al tubing and carbon