Thursday, October 24, 2013

Disc-Brake Road Bike (Part 1: Frame Research and Sourcing)

Behold the beginning of a new bike build.
Notice the little nubs near the dropout on the NDS chainstay.

Yes, I have decided to build a disc-brake road bike. I have used disc brakes on my mountain bikes (of course) for years; this past year I have done most of my day-to-day riding on a disc-brake equipped touring/cross bike (which is setup pretty much like an all-weather road bike). Ultimately, I am convinced of the value of disc brakes on the road. Not just for the wet days. Sure, disc brakes stop better when its wet, but they also stop better when it's dry. They also solve the problem of carbon clinchers and brake heat -- and the inferior braking on carbon brake tracks, in general. I love the idea of not worrying about taking carbon clinchers on rides with significant descents.

There are many that say that disc brakes on road bikes are unnecessary; I agree with that, but this same argument could be made for any number of cycling innovations over the past hundred years (indexed shifting, 10-speed cassettes, 11-speed cassettes, electronic shifting, etc.). Disc-brake systems are (still) heavier and give up some aerodynamics, but the technology is indisputably better at one thing: stopping the bicycle. It is clear that discs are here for the long haul on road bikes. You don't have to look much further than the current cover of Bicycling magazine to see that this is an idea whose time has come.

Of course, disc brakes are still not UCI-legal for racing, and the marketing machine for bicycles is heavily driven by the pro peleton.  So buying a disc-brake road bike now is jumping the gun a little, because despite there being an option from most of the bike manufacturers, the market hasn't quite exploded yet and some of the components are still a bit pricey (hydraulics, for example) .  And because they're not UCI legal yet, the vast majority of the frames that are out there are "endurance road" which basically split the difference between a road and a touring frame (longer stays, taller head tubes, clearance for larger tires, etc.).  While I don't need a pure race bike, I definitely want something more race-y than my commuter.  This bike won't need fenders or tires larger than 25mm.

Frame Research

I do love titanium, but my only marginally affordable titanium option is [somewhat ironically] building a custom frame through Habanero -- or custom frame direct from China. No, for this first foray into disc-brake road bikes, I am going to purchase a stock carbon frame direct from China.

I started by surveying the market to figure out what the options were and which frame was going to be the closest fit.

There are a few few main / "big-name" (relatively speaking) frames and then a few additional ones that can be found on; I'll just address the main ones here. Also I'm only looking at frames which offer a 60cm size or similar reach (the stack/reach numbers vary quite a bit), which definitely narrows the field.

Hongfu/Dengfu (Flybike factory) FM166

Hongfu and Dengfu are just distributors here; the FM166 is the same frame. Ordering from Hongfu or Dengfu seems to be more a question of customer service than anything else.

Here is a good youtube review of this frame:
Hongfu/Dengfu FM166 Geometry  
(The headtube angle appears to be wrong in this table.)

On the whole this frame was near the top of the list for me.

Hongfu/Dengfu (Flybike factory) FM079

For 2014, there is a new bike available from these guys which looks very similar to the FM166; however, it has significantly different geometry options. If the FM166 does not fit, you might wish to check this one out.
Hongfu/Dengfu FM079 
This frame provides more reach but also more stack with a 200mm headtube (for size 60); I want the flexibility to have a slightly more aggressive drop without a -17-degree stem.

FlyXii FR-320

At time of writing, this is the only Chinese disc-brake road frame that is available on ebay.  This one doesn't come in a size 60; I briefly considered it anyway, since the geometry matches my Motobecane frame almost exactly (and with a short headtube the reach is comparable to some of the 60cm frames).  The deal breaker for me is the 402mm chainstay length. For comparison, the other frames here have 410mm or 412mm stays (even that may be pushing it, we'll see).  I cannot fathom how the heel of my size-48 shoe would not be hitting the calipers (or the chainstays) with 135mm rear spacing.  It's close enough on my 405mm chainstays with 130mm rear spacing.

Carbonal Talia Disc

I don't know much (anything) about this company, but I came across their products and they seem legit enough to mention here.

The geometry on this one is fairly short, though; the 60cm has a 58cm ETT.  So that was pretty much dead in the water.

Yishun FM145

Yishun is primarily known for their wheels, but they also make (or distribute) frames and they've been in business for at least a few years. Their frames come with a 2-year warranty, which is a little less helpful when shipping is over 10% of the frame price, but it's something. The reviews I could find were generally (but not all) positive; that seems to be about par for the course with these better-known mainland manufacturers. Gavin Wu responded to my email to their sales department and he and I were in regular communication through the ordering process.

FM145 60cm

(Note that there is an error in the schematic; the rear spacing is 135mm on this frame. Gavin was quick to respond that the schematic was wrong; hopefully the factory knows that too...)
One of the primary reasons I decided to go with Yishun was the excellent communication -- both in terms of responsiveness and in terms of language skills and bicycle knowledge / understanding (which definitely puts one at ease when ordering something sight-unseen like this).

I decided to not opt for any decals or painting. I'd kinda like to personalize it, but I honestly couldn't think of anything specific, so I ordered it in the [quite trendy] matte black UD finish.

The size I wanted was not in stock with the BSA bottom bracket, so a new one had to be ordered from the factory. It is scheduled to ship out this week, so I should have it in a couple weeks.

More to come!

Update: See part 2 for a look at the received frame or part 3 for the final build & impressions.