Bicycle Mechanics - top of tire rubs fork - wrong fork, wrong tire, or...

http://i289.photobucket.com/albums/ll203/spiritrider_2008/IMG_4464.jpgI recently inherited a 2004 or 2005 Trek carbon bike. On my first ride, I could hear rubbing, so kept checking the brakes. I finally determined that the rubbing is caused by the top of the tire rubbing against the front fork. I can eliminate the rubbing by deflating the tire somewhat, but think that the tire/rim shouldn't fit so tightly in the fork. Could it be that the bike was built with the wrong fork? Are the wheels the wrong size for the bike? Here are the particulars: frame = 52, wheels = Mavic SSC (622 x 13), tires = Performance Pro Roubaix (700 x 23/ 23-622). Any insights into this problem and how to solve it would be much appreciated.

That's weird. Generally the limiting factor on a front wheel is the brake caliper, not the fork.

Pics? I gather it's rubbing on the top of the tire, or is it the sides?

Yes, it's the top of the tire, not the sides. There is very little clearance between the top of the tire and the fork.

HA! I believe your tire is a Specialized Roubaix Pro. It should say Specialized on the side. If I'm wrong about this, then I'm wrong about the rest of it. I have the exact same tires, and even though they are marked as 700X23, the casing is actually 25mm wide. I'm not sure why Specialized did this, but my guess is your fork is very sensitive to size. If this is correct, the only fix is to get a true 23mm tire. Hope this helps.

I'm wondering about the fork. That bike should be able to handle a 700 X 23 or 25 mm tire with room to spare. Something's not right.

Al

Some forks are like that. Choose your tires carefully.

You are SOL. Your fork/caliper combo looks like it only takes 23c or lower tires.

Brake caliper not damaged, bent down, etc?

Yes, I'm concerned about the fork, too, but how could it be wrong? Did a fork for a women-specific get built on this bike? I can't figure out why there is so little clearance. My husband's TREK is from the subsequent year and there is a LOT of clearance between the top of his tire and his fork. I'm mystified.

But I have that size tire on the bike now.

No problem with the calipers. The rubbing is on the underside of the fork. If I get the tiniest bit of asphalt on the tire, it causes the tire to "stick" under the fork and presents quite a drag.

are you using the same tires? Can you ride the bike no handed? If you can't, the forks are tweaked, but carbon fiber shouldn't really bend, it'll break. If you and your husband are using different tires, try swapping front wheels and check the clearance. What model is this?

A women's specific fork wouldn't be designed with less clearance. Either your tire is just too big or your fork was manufactured poorly.

HA! I believe your tire is a Specialized Roubaix Pro. It should say Specialized on the side. If I'm wrong about this, then I'm wrong about the rest of it. I have the exact same tires, and even though they are marked as 700X23, the casing is actually 25mm wide. I'm not sure why Specialized did this, but my guess is your fork is very sensitive to size. If this is correct, the only fix is to get a true 23mm tire. Hope this helps.

O.K. This will be an easy test. I'll switch out the tire tomorrow and will post the outcome. I hope that you're right, because this will be an easy solution. But the tire is so tight in the fork that I am still concerned that the problem is in the fork, but I can't figure out how the fork could be wrong - unless it was really meant for smaller women's specific bike - or some such.

Thanks for the suggestion.

A women's specific fork wouldn't be designed with less clearance. Either your tire is just too big or your fork was manufactured poorly.

Ah, this is helpful, because that has been my biggest concern - that the fork was meant for a different frame size or some such. I'm switching out the tire tomorrow. With luck that will solve the problem.

Thanks.

the only size differences for road forks are ones that fit 700 wheels and ones that fit 650 wheels. If you had a 650 fork, you couldn't even cram that wheel into it. I'm still going with a tight tolerance fork and ridiculous sized tire. (I only say this because I run the same ones :D )

are you using the same tires? Can you ride the bike no handed? If you can't, the forks are tweaked, but carbon fiber shouldn't really bend, it'll break. If you and your husband are using different tires, try swapping front wheels and check the clearance. What model is this?

I'm fairly certain the fork isn't tweaked. We are using different tires. This is an even easier test to run. I'll switch wheels tomorrow. If that does the trick, then I'll change the Performance Roubaix that is on the bike at the moment.

Thanks for the suggestions. You've been very helpful.

I have a 2004 Trek 5500 that came with a Race X Lite fork with minimal vertical clearance for the front tire as well. The fork would just barely take the old Conti Grand Prix 3000 tires in a 700*25, but it won't take a Grand Prix 4000 in a 700*25, which is several mms taller than the old 3000. So I run a 25 on the back and a 23 in the front.

Regarding your Specialized Pro Roubaix tire, here is what it says on the Specialized website: <<Comfortable large volume 25c casing, merged with fast-rolling 23c Dual Radius Tread (DRT) ensure a supple ride that rolls fast and corners extremely well, all in one tire.>> So I don't think that tire comes in a legitimate 700*23 size. It is probably a nice tire though. Too bad it won't fit.

FWIW, Specialized tires seem to run larger than branded. Sheldon had an article on tire sizing that's interesting.

Yeah, tire sizes are pretty much like shoe sizes and clothing sizes (and frame sizes for that matter). one manufacturer's 23 is anothers 25.

are you using the same tires? Can you ride the bike no handed? If you can't, the forks are tweaked, but carbon fiber shouldn't really bend, it'll break. If you and your husband are using different tires, try swapping front wheels and check the clearance. What model is this?

Many thanks, UnsafeAlpine. I followed your advice and swapped my husband's wheel for mine - it provides considerably more clearance. I'll buy a new tire.

are you using the same tires? Can you ride the bike no handed? If you can't, the forks are tweaked, but carbon fiber shouldn't really bend, it'll break. If you and your husband are using different tires, try swapping front wheels and check the clearance. What model is this?


I have a 2004 Trek 5500 that came with a Race X Lite fork with minimal vertical clearance for the front tire as well. The fork would just barely take the old Conti Grand Prix 3000 tires in a 700*25, but it won't take a Grand Prix 4000 in a 700*25, which is several mms taller than the old 3000. So I run a 25 on the back and a 23 in the front.

Regarding your Specialized Pro Roubaix tire, here is what it says on the Specialized website: <<Comfortable large volume 25c casing, merged with fast-rolling 23c Dual Radius Tread (DRT) ensure a supple ride that rolls fast and corners extremely well, all in one tire.>> So I don't think that tire comes in a legitimate 700*23 size. It is probably a nice tire though. Too bad it won't fit.

You were right - it's the Roubaix tire. I followed UnsafeAlpine's advice and switched my husband's TREK front wheel for mine and there is plenty of clearance.

Yeah, tire sizes are pretty much like shoe sizes and clothing sizes (and frame sizes for that matter). one manufacturer's 23 is anothers 25.

You're right, Tellyho. Although this tire is marked as a 23, it is a oversized. I swapped my husband's TREK wheel (with a different tire) and it fits just fine. Whew! Just a "bad" tire.

I'm glad that was an easy problem to solve. Stay clear of Specialized tires because they all seem to be oversized (which is unfortunate because I've had great performance on mine.)

Aww... I was hoping that this was some kind of super freak bike thing.