[Dresden]

What's the concensus of the experts? Opinions seem to range from "If the tire isn't rubbing, it's fine." to "You need quite a bit of clearance or some gravel will get stuck between the brake/fork and tire, lock it up, and you'll fly over the handlebar and die."

 

[tihsepa]

On the road? I am in the "minimal" camp. If it dosent rub, it will be fine.

I love that "picking up gravel" story. Heard it a bunch of times, seen marks on the bottom of a fork crown, never seen it happen where someone went OTB.
Keep in mind a bike with that tight of clearance shouldnt be ridden in the gravel anyway. i am not saying a road bike cant handle gravel but not when the clearance is that minimal.

 

[wim]

On the road? I am in the "minimal" camp. If it dosent rub, it will be fine.

I agree. When you design a performance bike, you just have to put aside some considerations about remotely possible worst-case incidents.

As an aside: Not saying it happens a lot, but the possibility of going over the bars because a foreign object blocked the front wheel is real. The reason it appears to be so rare is because the unfortunate rider usually reverses cause and effect and blames a sudden fork failure for going over the bars.

But a foreign object can wedge itself between the tire and fork and instantaneously block the front wheel. When the rider and the bike has rotated up about 45 degrees to the road, the now-cantilevered fork is loaded beyond its strength and usually breaks as shown in the photo below. The foreign object often falls away and is never found, so it's understandable that the rider will blame "fork failure" for what was actually caused by a momentary front wheel blockage.

 

[Mike T.]

The unit of measurement, back in the '70s & '80s, in the UK for close-clearance racing frames (usually TT frames) was "*** paper".

The "*** paper" measurement was the thickness of the paper used in hand-rolling cigarettes (very thin). "***" at that time was the slang term for a cigarette.

And yes, with some frames, it was hard to see daylight between tire and seat tube. I'm happy to see that it went out of fashion.

Edit - Hahahaha, RBR's famous filth-filter filtered the word f-a-g.

 

[tihsepa]

The unit of measurement, back in the '70s & '80s, in the UK for close-clearance racing frames (usually TT frames) was "*** paper".

The "*** paper" measurement was the thickness of the paper used in hand-rolling cigarettes (very thin). "***" at that time was the slang term for a cigarette.

And yes, with some frames, it was hard to see daylight between tire and seat tube. I'm happy to see that it went out of fashion.

Did you say ***?

 

[Mike T.]

Did you say ***?

No, I typed it. But it was in a "good" context and it was quoting a term. Even newspapers are allowed to use filthy words like ******* if they're used in a quote. Hopefully I won't get a lifetime ban form RBR. If so, I'll try a bribe.

Edit. Haaaa, I just saw your sig. Toooo ******** funny!!

 

[Alaska Mike]

You also have to factor in wheel flex and rider weight. I tend to prefer more clearance, because I've had spokes break and the wheel deformed into the fork. Granted, it was with a low-spoke count wheel (16), and that problem is mitigated somewhat by higher spoke count wheels. That's one of the reasons my training wheelsets have 28 spokes or more.