i switched to 700x25 tires from 700x23. Looks like the top of my front tire makes contact with the bottom of my brake caliper while riding. It’s just a slight rub and I still rode 55 miles fine yesterday but maybe the tire ended up getting a little shaved. Any way to fix this?
Switch back to 23mm?
No other way?
Try a different “25mm” tire. Some are taller (GP4000) than others.
Or go with a 24!
Try a different “25mm” tire. Some are taller (GP4000) than others.
These are GP4000s ii… I guess I need a different less taller tire?
What bike is that ? My pal rides a Tarmac s works with 25mm contes and Red calipers ?
if you haven’t yet, try opening the brake caliper a little (with barrel adjuster or quick release lever). should give you a little more clearance, as long as you can still pull the brake all the way to the rim.
Try swapping out your brake. There has to be one that “sits” higher than the one you have. David K
That tire is mounted backwards 
.
This if you must run the 25mm.
For instance, Omegas allow for vertical adjustments to the caliper body.
What bike is that ? My pal rides a Tarmac s works with 25mm contes and Red calipers ?
Its a tarmac sworks with 25mm gp4000sii and red calipers… I think I will try to open up the brakes a bit see if I can add 1mm clearance.
I may be totally wrong, but this looks like the same sh------ problem I have had with a small QR CDO.1 frame using TRP brakes. When you widen the calipers for more clearance (Zipps and 25 mm Conti 4000’s), the arm actually moves down toward the tire. It seems counter intuitive but to gain clearance above the tire, you have to squeeze the caliper arms closer together to make them arch higher. I was able to do this by replacing the wide “wobble washer” between the pad holder and the caliper arm with a thin stainless steel flat washer. Some people have also suggested grinding down the brake pads (no effect on braking ability - just less mileage on the pads) so you can set the arms closer before contact. I finally decided that they were just too close and went back to 23 mm tires. With the thin washers, they gave a good clearance.
Hi, yes I gave it enough clearance by doing what you said. First, I swapped out the brake pads for swissstop low profile black prince pads, which is less bulky. I then adjusted the calipers closer to the wheel by squeezing on them and locking them in place; and that looks to have given enough clearance to not rub. Will test this out next week on actual ride!
I may be totally wrong, but this looks like the same sh------ problem I have had with a small QR CDO.1 frame using TRP brakes. When you widen the calipers for more clearance (Zipps and 25 mm Conti 4000’s), the arm actually moves down toward the tire. It seems counter intuitive but to gain clearance above the tire, you have to squeeze the caliper arms closer together to make them arch higher. I was able to do this by replacing the wide “wobble washer” between the pad holder and the caliper arm with a thin stainless steel flat washer. Some people have also suggested grinding down the brake pads (no effect on braking ability - just less mileage on the pads) so you can set the arms closer before contact. I finally decided that they were just too close and went back to 23 mm tires. With the thin washers, they gave a good clearance.
Weird. The sl4 copes just fine with those tyres.
Weird. The sl4 copes just fine with those tyres.
it’s an issue with older sram brakes–low brake arch.
I was going to ask if you had Red Aerolink brake… and now I can see you do from the pic. That’s the problem, very little clearance with that brake and the GP4000 II S tires are a bit taller tires. I put on some new tires recently after I had upgraded to the Red brake before a race… bad idea. I wore a groove into the brake and the tire, they were still rubbing.
I had my bike shop toss an older DuraAce brake on, the clearance is just too tight on that SRAM brake IMO.
Get a Dremmel to take care of that.
One other thing I noticed on going back to a 23mm tire is that the height of the tire, when in the wide Zipp wheel, is considerably reduced. Visualize the cross section of the tire and spread the bead and sidewalls farther apart. The top (tread) of the tire will move down. The 23mm and 25mm could have the same height at rest, but when you stretch the 23 wider to fit the wider wheel - the top comes down to make a less tall tire. This allows you to open (and thus lower the clearance) of the brake arms/pads but still easily clear the tread.