ColaJacket

Cool, then I can gain at least 8mph once I lose all the weight I need to lose.

GH

calimtb

Yikes!

You can do it. You might lose that weight before I drop the 5 lbs. I want to lose.

rpenmanparker 

That's about right as far as I can tell.

rpenmanparker 

As the miles pile up, my initial opinion is being confirmed. Great frame. Rides great except for a slightly higher amount of shock transmission up to the rider than I am accustomed to. Perhaps that is just the necessary trade off to get more lateral stiffness that I simply am unaware of and disinterested in. Dunno.

Stucky

Glad to hear it!

Just [STRIKE]to be a pain[/STRIKE] for curiosity's sake, how does it compare to your steel bike?

BoSoxYacht

Your reviews are what I expected. Nothing bad about the frame in particular, it's just not the most comfortable. This is pretty common for very lightweight frames.

If the manufacturer uses a lot of Hi-Mod CF, less of it is needed to produce a stiff frame, so the result is a very light and very stiff frame.
The problem is that the frame isn't very comfortable, and is a bit fragile and easily damaged by non cycling-impacts.

Derailleured

Rpen: I applaud your message threads. At the very least, it is nice to read about a person that has intellectual curiosity about their hobby.
Have given some thought to the push back, especially from the person with quality control experience in the auto industry. Gosh, how well did
that work for Volkswagen? A close friend bought a BMW new and the engine didn't last 30,000 miles. Don't be so certain that German engineering
is light years better than Chinese engineering. China has more Chinese honor students that the US has total number of all US students.

Here is a conclusion from your experiment: the major bike manufacturers make a profit selling CF frames for thousands of dollars. The Chinese manufacturer
that you bought from makes a profit selling the frame for around $500. So, kudos to you for building a bike with no added profit in a situation where that profit could be considered
padding to the manufacturer. Quality control should not add hundreds or thousands of dollars to a bike frame cost.
Turning our attention to safety, let me say this: I ride an aluminum frame TREK. Therefore the quality control should be at
a certain level of dependability. Still, when I exceed 30 mph going down hill, I feel both exhilaration and trepidation. I trust the bike and it does feel stable
at speed but I still have apprehension about ending up dead or in a wheelchair. SO...I ride the brakes and any of you can call me gutless. For those of
you that go down hill very fast, what bike do you trust?

Rpen: How far do you trust your Chinese frame? How fast will you go downhill
on your new bike? Again, I have only compliments and look forward to reading
about your next experiment.

Side note to Rpen: how have you learned your bike assembly skills? Do you refer to specific
non fiction bike books or Park Tool guidance, etc.?

rpenmanparker 

I have donated all my hamers to Goodwill. Thanks for the comments.

rpenmanparker 

Little by little over three decades. After about 3 years of doing what maintenance was needed, as needed, I started building wheels and switching parts to new frames. That was about 30 years ago. It just grew from there. Just about everything you need to know is included in the package insert with a new part like a derailleur for example. But Parks website is excellent for jobs you need help with. Also many, many You Tube videos.

rpenmanparker 

Very good question. Actually my steel bike is very stiff. Heavier than necessary stays and lugs, investment cast bottom bracket shell, etc. though the tubing is light. Both the Giant and the Merlin were/are more comfortable than the steel Romic. The new Chinabike is very similar to the Romic. Maybe not precisely the same road feel, but the transmission of impacts feels very similar. I will need to take the Romic out for a spin soon to get a more conclusive comparison. It has been a while since I rode it.

Maelochs

VW had no QC issues ... they were deliberately gaming the testing system with software which changed the engine performance when it ran government test loops.
Absolutely, going very fast downhill can be scary (for some riders, like myself.) However, being reasonable, I have to admit that tires/tubes are a far more likely source of equipment-related wipeouts on a fast downhill versus frame failure. Rider error is Always the leading cause on accidents--maybe getting scared and squeezing the brakes too hard, maybe not seeing some road debris or pavement imperfection, maybe pushing too hard on a corner, whatever.

If I had rpenmanparker's bike, I would take my speed up slowly on those fast downhills and figure out if anything felt wrong. If not, I would then trust the frame as much as I would, say, a Nashbar carbon frame.

If rpen had bought a counterfeit (a frame pretending to be a name brand) I would have cautioned him against it--a company that will deliberately lie and cheat to make a buck isn't likely to care a lot about QC. However, there is no reason to suspect that every smallish factory in China is building dangerous merchandise just because they have maybe reverse-engineered some well-known western product (ref. the entire Chinese auto industry.)

I understand his frame is not a Cervelo Rca (or whatever,) even if it looks very similar and weighs about the same. I also understand that it could be a competently made frame which will provide years of safe performance and pleasure.

Equally, it could be unsafe at any speed--not likely IMO, but the possibility exists. But then there is also the (much rarer) possibility that he could have bought the random Cervelo frame which had some invisible flaw and which cracked at speed and wrecked him. Stuff happens.

People who buy knock-offs to get the label are getting exactly that--the label. But sometimes, people who shop around for a bargain get exactly that. Not quite as good as a real Cervelo frame, but a small percentage of the price for a large percentage of the performance.

We shall see what is said a couple years from now when he sells the thing for a fair price and reports that he got several thousand highly enjoyable miles out of it and is now ready to build something new---or when he posts here about its failure.

Either way, a really entertaining thread, an experiment I am considering for myself someday (because I love putting together bikes, not because it would be the best performance bang for the buck,) and I look forward to reading about his feelings about the bike as he logs more miles.

Stucky

Thanks. I think that's what it all basically comes down to: Road feel, and which one the rider personally likes. I dopubt we'll ever get the same road feel from CF that we can get with real metal- but the fact that these modern CF are matching the characteristics of good quality vintage frames in every other way, is a sign that the engineers are doing their jobs! I'll be interested to hear your take on the Romic vs. the Charlie Chan Special.

I wish that I had more interest in modern CF bikes, 'cause I enjoy building bikes too, and I could see myself building one of these Chinese frames, just "because". (and to give it a nice custom paint-job)

rpenmanparker 

In response to Stucky's inquiry I rode the steel Romic today over the same course as I have taken the Chinabike, and it was just as I remembered it. Very quick and agile, no flex to speak of, and a little sharp over the bumps. Now keep in mind I rode this frame for almost 20 years with never a thought that it was uncomfortable. On the contrary I would have defended its comfort to great lengths. But that was before I experienced the Giant CF and Merlin Ti frames. While I still love the Romic, now I know that it is possible to have a much softer riding frame without undue flex.

I would estimate that the Chinabike is just a little softer riding than the Romic over the road defects and just about as quick in the front end. You should know that the Romic is the quickest handling bike of any I have ever had, so that is saying something. Stable but very responsive.

That is all.

Stucky

Thanks, RPenn.

Wow....that review makes me think very highly of both the Chinabike and the Romic! Very impressive for the Chinabike though- considering the price and weight..... I'm almost tempted to try that one myself. (Might just do it....)

ColaJacket

Well, I am a regular poster in the Clydesdales/Athenas forum.

GH

Jarrett2

That reminds me of that Chet Atkins quote where someone came up after a performance and said that his guitar sounds good. He put it down on the guitar stand and said, "how does it sound now?"

Jarrett2

Steel.

Plus it weighs like 5,000 lbs. (because its steel) so it goes down the hill SO fast

rsilvers

Using the same tooling would not mean the same product if they used lower modulus CF or didn't orient the directions correctly. But on the other hand, I think there is a significant chance it would be just as good.

But if the odds are 25% that it would be just as good, and then why not just buy a one-year old Giant Propel for $1200 and be done with it?

I considered making a Chinese generic bike, but then I added up the cost and it was about $1800 in all. And then I saw small companies selling such bikes already build for $1300 slightly used 2015 models, and thought it would be better to just buy one already assembled from them. And then I realized I could just buy a Fuji all-carbon bike for $1500 new on sale with Ultegra at the local bike shop. And then I realized I could buy a Giant Propel-A2 new for $1900. And then I realized I could just buy a dream bike used for a few months at 1/2 price. The more I looked at the options, buying a frame from China and building it made less and less sense.

rms13

None of those options will be close to 15 lbs let alone 13 lbs

rms13

So I decided to swap out my Ritchey WCS carbon seat post for the one that came with the frame and it actually made the bike more comfortable. Combined with my 90/80 psi tires even the fresh chipseal I road today wasn't bad.

I also hit 39.6 mph descending today without any kind of shuttering from the bike or front end. I could have got over 40 but I'm a wuss

rsilvers

True. UCI should lower the limit to 12-13 lbs due to how such bikes are possible to be safe now if built correctly using the latest advances in carbon fiber.

rpenmanparker 

I want to share a rather bizarre impression with you all as an update to my Chinese frame build. You will remember I described Ford's ride as harsher than the Giant TCR Advanced it replaced and also rougher than the Merlin Ti bike I also have built up very much the same way.

When I reported that, I had been testing it out with the 25 mm tubular tires inflated to 75/90, very soft by some standards, but probably okay for tubulars which can't pinch flat despite my 170 lb current weight. Certainly the 25 mm width suggested fairly low pressure would be in order. Anyway I decided to make a change. Would you think lower pressure to try to soften the ride some? This may shock you, but no, I actually decided to pressure up a bit. So I have been riding the bike at 85/100, and don't ask me why, but for some reason it seems more comfortable. I can't explain it, but there it is. I like it better at the higher tire pressure. Go figure.

Bunyanderman

For some weird reason, this is my favorite post over the last month or so.

rms13

Interestingly, I decided to replace my Ritchey WCS carbon seat post with the generic carbon post that came with the frame and my bike became much more "vertically compliant"

BoSoxYacht

As I would have expected. The generic carbon post has more goodly flex.