[cs1]

Anyone build a bike with the Motobecane Phantom Cross frame? I'm not talking about a complete bike but your own build using their frame. $389 shipped with a fork isn't too bad a price.

I've got most of a Campy group in the parts bin and was thinking about building one up. Any thoughts?

cross posted on bikeforums.

 

[OnTheRivet]

Personally, I'd go with the Performance frame (3.6lbs) 225.00 with fork and headset. And use the extra dough to get a good carbon steerer fork like the one listed.

Frame

Fork

 

[cs1]

Personally, I'd go with the Performance frame (3.6lbs) 225.00 with fork and headset. And use the extra dough to get a good carbon steerer fork like the one listed.

Frame

Fork

Does a CF steerer really save that much weight? I'd rather have a stronger steerer tube, especially in an area as highly stressed as the fork.

 

[krisdrum]

How much stress does a steerer really have on it? Those Moto's build up pretty heavy for what they are if I understand correctly (check out the Fuji frame and bike weights). The Performance frames are supposedly Redlines. The issue I've encountered with the Scattante, is in smaller sizes, the compact front triangle is too small to shoulder. At least that is what I have found with the 48. So the Moto could be worth it if you need the smallest size.

 

[PeanutButterBreath]

I have the Scattante, and the stock fork weights about 650g, IIRC. That's close to a 1/2 pound heavier than the Origin8 fork that was linked to.

CF in a steerer should be as strong or stronger than Al. Assuming proper manufacture and installation, its main vulnerability is to crash damage, from which a fork steerer is insulated by the frame's head tube and the stem/spacers. The normal stresses that apply to a steerer should not pose a challenge to CF.

 

[Dynastar]

I have that frame and race it, but I have to admit it is a little heavy.

 

[tron]

I picked up a redline conquest pro frameset for 399. It was surprisingly light

 

[Will Be Was]

I have race the that Moto, it is a contender.

 

[cs1]

CF in a steerer should be as strong or stronger than Al. Assuming proper manufacture and installation, its main vulnerability is to crash damage, from which a fork steerer is insulated by the frame's head tube and the stem/spacers. The normal stresses that apply to a steerer should not pose a challenge to CF.

 

[krisdrum]

You have no idea what the circumstances are behind those crash images. Everything breaks eventually, especially when an immovable object is involved.

 

[cs1]

You have no idea what the circumstances are behind those crash images. Everything breaks eventually, especially when an immovable object is involved.

Just saying.

 

[PeanutButterBreath]

Hincapie.

 

[krisdrum]

Just saying.

Sorry, my analytical nature doesn't compute. Saying what? That carbon steerer tubes break? Of course they do. I'm sure if you look, you can find some sheared alloy steerer tube pictures too. Are carbon tubes more prone to break than alloy? Maybe. But I don't see any data to support that. I know one thing, they seem to take a nice chunk of weight off the front end of my bike and make it easier to portage. Until mine snaps off and leaves my family cursing cloth and epoxy, I think I'll keep using mine.

 

[OnTheRivet]

Hincapie.

Hincapies steerer was aluminum. The used a star nut to install the headset, when they tightened the top cap the star nut spun scoring the inside of the headtube, presto "look ma, no hands"

 

[PeanutButterBreath]

Hincapies steerer was aluminum. The used a star nut to install the headset, when they tightened the top cap the star nut spun scoring the inside of the headtube, presto "look ma, no hands"

My point, exactly. Al steerers can break too, even when installed by pros.

Can a star nut be installed without scoring the steerer? If it is loose enough to spin when the headset is pre-loaded, how can it be allowing pre-load to be applied? Weird.

 

[cs1]

You have no idea what the circumstances are behind those crash images. Everything breaks eventually, especially when an immovable object is involved.

The Trek in photo 2 is described here. It's not an isolated incident either.
http://velonews.competitor.com/2010/06/news/steered-wrong-racers-concerned-about-broken-carbon-steerer-tubes_121389

 

[Coolhand]

The Trek in photo 2 is described here. It's not an isolated incident either.
http://velonews.competitor.com/2010/06/news/steered-wrong-racers-concerned-about-broken-carbon-steerer-tubes_121389

Its not a cross bike either.

 

[PeanutButterBreath]

So buy steel fork -- its only an extra pound and a half or so. You'll be faster if you aren't paranoid about your fork breaking.

 

[cs1]

So buy steel fork -- its only an extra pound and a half or so. You'll be faster if you aren't paranoid about your fork breaking.

Good point.

 

[weltyed]

nor does it have the required 5mm spacer above the stem.

Its not a cross bike either.