I don't think that will work. The spacers would give you more room between the tire and the top of the brakes, but the brake arms are probably not long enough to reach the brake track after that. You would/will need long reach brakes.

Yeah, this was to avoid the long reach brakes. I had thought about that. We're talking $40 vs. over $250 for brakes.

The stock brakes have the pad shoe screw that isn't recessed, so you could probably gain a mm or two there in that slot no problem.

I wound up finding someone who did this for this type brake on another bike.

I resisted a long time but eventually bit the bullet for the Fouriers brakes, and they are absolutely worth it. In addition to the added clearance it's a simplified design with fewer bolt types. With the stock TRP brakes I was, after a year, having to tear them down and clean/grease every few rides, especially in the wet, to keep them centered and working properly. Fouriers = zero maintenance required after 2-3 years of operation, still work absolutely great. They are expensive, but they are a great product. Should have been included on the bike from the start.

I would have done the Fouriers already, but my stock brakes have given me ZERO problems so far.

Early in ownership I disassembled and cleaned them once and lubed them up really well and have kept them clean and lubed well and haven't had to touch them. They stay perfectly centered and work great.

These are clearly Giant stamped on them, but I haven't had any trouble at all like you describe. This bike has well over 7000 miles on it.

Oddly enough the rear looks like it could do it as-is right now without a modification. But the front appears a touch closer to the wire to me than the back.

Glad to hear they are working well. As I recall my experience was similar in that one brake (I forget which) was significantly closer than the other.

If it ain't broke, don't fix it, though running 25's doesn't hurt.

I threw a shim in last night using some scrap........dropouts aren't deep enough to do it. Not even close.

So, this is officially dead.

yes, have them on a NP3 that has a dropout screw broken off at the frame. they work well, although are a pain in the ass when you want to install/remove the rear wheel.

Are you sure you need the full 5mm to use the 25s? I kinda doubt it.

I recently cut a dropout width of a ziptie and put that in each of the front dropouts on my Allez sprint for a gravel/road race. Gave me an extra ~1mm clearance that let me run 28s a bit more comfortably. I'd suggest trying that, basically spacing the wheel 1mm at a time until you either clear your tire, or run out of dropout space.

I have had some 28mm gators on the original alloy aero wheels from the bike to use on my cross bike.

I threw those on the Propel tonight, 28’s, and they fit.

Literally a zip tie width on both will work. I think I already have the updated Giant version of brakes for 25mm tires. Hence why it seems so spacious already. The 28s fit without a zip tie and you could spin them but the wire would touch barely when you pull the brakes.

Given that a 28 is a zip tie away from fitting I may research some 26mm tires for mixed road gravel use and call it good. Specialized Turbo Pro in 26mm may be the medicine.

25c will fit the propel no problem
Had 28c GP4k and one of them was too close (forgot if it was front or rear)
I resisted for years before forking out $100 for the fourrier, when I did I regretted not doing it earlier.

Same here. I think Giant/TRP is on the 4th generation of the propel brakes and they're all terrible. I found I was spending a couple of hours every month adjusting them, on regular brakes it would be about 30 mins a year.

I spent $80 on a Fouriers for the rear. Works great, and will easily clear a 29 mm tire.

I've built up the dropouts on a steel bike before and just adding 2 mm made an enormous clearance difference. 5 mm might be too much. One can file down the surly spacers or build up the dropouts with a shim or jb weld. I'd be reluctant to do this on a carbon dropout though - unless it had been damaged and you're restoring it.

I think it depends on when it was made. My Propel is a ‘17’ (I think) and it came with 25mm tubeless on giant SLR RIMS. Brakes work great and have never given me any trouble but I think there where different brakes on previous versions that got a lot of complaints.

The 28mm Gators made it great through 54 miles of hilly mixed surface riding. I made a lap course of Umstead big loop but taking Ebeneezer rd back instead of Turkey. Was nice.

I can go faster down a few gravel hills on the cross bike but flat or road, this was faster.

No issues! So, now I know.