rosefarts

I got some new tires on my bike. 30mm wide, which definitely weren’t a thing when this bike was new. I have to inflate the tires when they’re on the bike, I’m ok with that.

I have heaps of fork (and frame) clearance. They’re pretty much perfect in the back.

Up front, the manufacturer mark on the center of the tire just barely touches the underside of my calipers. I can hear it in a quiet garage. It doesn’t seem to slow the wheel at all.

I’m sure that in time, the tire will wear just enough to stop this. Ideally though, I’d like a squosh more clearance so every grain of sand I ride over doesn’t make noise.

I will not be replacing the calipers. Nor will I file the underside.

I have two ideas, unsure if they’ll work. One is to use a couple washers and extend the calipers a few mm from the fork. This might give me a little clearance because geometry. Then it’s just a simple pad adjustment.

My other idea would be to install some sort of spacer, not more than a mm thick, into the fork ends. It would still give me plenty of space to clamp the qr and should open up the space a tiny bit. Basically I’d put a teeny bit of a soup can in the top of the fork ends. Seems a little fiddley to me though.

Are there other more convenient or obvious alternatives? I’m not married to these tires. They’re new, I got them from someone on marketplace along with some other higher value items, so whatever. Still, I’m kinda in love with that rowdy look and would like to try them if I can.

Pics show how tight the clearance is up front and one pic to show that these calipers have more than enough room in the rear.

Aubergine 

TBH I would simply not use those tires.

smd4

Well, on the plus-side, you won't need to install a tire-saver on the front.

Iride01 

Wider is better. Now that you can't get any wider on that bike, you'll never have better!

13ollocks

Yikes - that's tight. Certainly try a spacer as a quick and cheap approach to move the caliper forward a few mm, but I don't think it's going to buy you any meaningful increase in clearance. Since you appear to have a few mm of leeway in your brake pad adjustment, could you adopt a drop bolt to move the caliper up a few mm? This is a vintage Campag drop bolt to give you an idea, although this was intended to adapt 27"-fit calipers to 700C wheels - and I don't know if I'd trust my front brake to a jury-rigged vintage part. In your shoes, I'd be inclined to simply put a 28mm on the front - you're still getting some benefit, and your arse will appreciate the 30mm on the back.
I'm in a similar boat - I'm limited to 25mm tires - I might fit a 28 on the back (and I know my Campag calipers will accommodate 28s - just) but anything more than 25 in front would have the tire brushing something - that's too tight for my comfort.

Koyote

The best solution is different tires.

Troul 

fork washers & caliper spacer might be the best work around... otherwise, toss the entire wheel in the dryer on high for an hour to shrink it?

grumpus

I wonder what would happen if you could place a sliver of shim under the front of the brake bolt, and another over the back of it, or even just wedge something under the brake as you tighten its bolt. Otherwise geometry works - it's little effort to see if you gain worthwhile space without it looking crap or getting wobbly - might need a longer nut. I think shimming the axle down would require careful fitting of the part, probably starting with a slice of 10 mm round bar and a file, and some sort of bonding agent to be sure it stayed where it should, if it wasn't tight enough to wedge in place.
Running such a close clearance is potentially dangerous for the tyre - if a sharp piece of road debris gets picked up by the tyre and jammed under the brake it can slice the tyre, so a thorn catcher would probably be a good idea.
[edit]I just thought, if you make a steel shim for the dropout, you could solder it to a washer to hold it in place.

rosefarts

Did Benjamin Franklin give up so easily at Gettysburg?
Did Albert Einstein say we can't go to mars?
Did the Wright Brothers fly coach?
Did John Connor say "I'll be back"?

Hell no brother!! Who's with me?

Koyote

Very cute reply.


Now get new tires.

Iride01 

Did he? Maybe so. But wasn't the T-800 Terminator the fist? John Conner hadn't been born yet.

rosefarts

You gotta admit, a handbuilt steel bike from 2001 rocking a pair of 30mm balloons would be really cool.

Its so close.

rccardr 

You gotta admit, there’s virtually zero visual difference between 30mm and 28mm tires. Both look cool.

On the other hand, there can be significant difference in your face between riding tires too large for the fork and ones that won’t jam and lock up the front wheel.

FBinNY 

Tire clearance isn't horseshoes. Close doesn't matter. If the OP is talking about the molding flash or risers touching he can safely ignore it. Or he can spin the wheel against a razor knife to trim it in lieu of waiting for it to wear off. As for the actual tore touching, that would be a nono, but ANY clearance is enough.

I have a front brake on my street use track bike, and it's tire clearance is near zero. It's so close that I can hear the zzzzt of momentary contact on hard bumps, and any grit carried up on the tire squeezes by and gets pinged out the front at high speed. It's been that way forever, and you can see trace wear on the brake, but not enough to fret over.

Steve B.

This ^

I’d try a 28

prj71

Nothing like shoving 10lbs of crap in a 5 lb bag.

BF never ceases to amaze with the weird things people want to do.

70sSanO

Make sure you carry a spoke wrench.

John

JohnDThompson 

Upside-down "drop bolt?"

I'd be concerned in running with clearance that tight on the front wheel. Something that sticks to the tire could jam under the caliper and lock up the wheel, causing a crash.

Looks like plenty of clearance on the back; maybe just run a narrower tire on the front?

rosefarts

Molding flash seems like a good term. Yep, new tires and what rubs is the rubber that’s leftover that isn’t actually the tire.

FBinNY 

Mold flash and/or risers (those little whiskers on new tires) are artifacts of the manufacturing process. In other applications they're removed at the factory, but nobody bothers on tires because they'll wear off so quickly in service.

Feel free to ignore them, along with the advice to make any kind of change.

veganbikes

Benjamin Franklin's America hating ass was a draft dodger during the Civil War. He had the courage to play with his kite but when America needed him to serve he was nowhere to be found. "Oooh look at me I have time to put my face on money but not enough time to serve our country"

rosefarts

Thats just what this thread needed.

FBinNY 

Seriously hope you were being facetious, but these days we can never know. So just in case ---------
Franklin wasn't young at the time of the Revolution, and would have been well over 100 during the Civil War, had he lived that long.

FBinNY 

FWIW--

You come here for free advice, and certainly have no obligation to listen

However, it's bad form to tell those who've you came to for help, that you don't like what they suggest.

squirtdad

not me....get 28mm