It's been my experience and I've seen reported that 25c michelins usually run close to 27 on standard width rims. Did you caliper them to see actual width on the Flo wheels? I think it may be worth pointing out that some 25s may work, just not this combination(large volume tire on wide rim).

I've got 25c Conti 4000s tires on my 404 FC wheels that I use for road racing. I also use them on my TT bike for training so I don't have to mess around with the brake adjustments from my normal TT wheels.

On my road bike a BMC SLR01 with SRAM Red brakes the clearance is extremely tight. Vertical, not side to side. So tight in fact that at the Mt. Hamilton RR this last weekend my front wheel picked up a small rock that stuck to the tire until it got to the brakes and jammed. I basically skidded to a halt and had to spin the front wheel backwards to clear it and then chase back on. Lots of fun. Thankfully it didn't happen on the descent.

Similarly, when I used to use 23's the 404's were no problem in my Shiv (TT version), but the front 25 rubs on the fork so I can't use that wheel and tire on the TT bike and I've been using my 808 FC clincher for training rides.

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Kevin

http://kevinmetcalfe.dreamhosters.com
My Strava

That is strange. I was running 25c conti gp4000sii on flo 30 rims with atleast an inch of clearance on my 2015 mens slice. Didn't know there was a difference. Can you show a picture of it?

Also what kind of front derailleur are you running?

As others have said, 25c Pro 4's run at 27mm+. Use a different tire.

She is 5'4" so the bike is a 51 maybe? Not sure, whatever the LBS said fit. It is the Ultegra build, and the problem is where the cable leaves the derailleur and goes into the frame. For some reason it crosses right in front of the back tire.

I did notice that the tires have a very tall aspect compared to the 23C on my bike when I installed them, but I thought that was just an optical illusion since they are all black, no colored sidewall at all, unlike my Turbo Cottons. The LBS caught the problem yesterday while changing the aero bars to ski-bends, the first time they had seen it in full race dress. The rubbing is very light. You don't notice or hear it unless it is on a stand in the shop, or you look closely. She has been riding the bike for several months and 100's of miles and it has only slightly abraded the tire. I'm tempted to leave it alone, but since my wife is riding it...

I went with 25c because she only weights 110 lbs. so she had trouble pumping up tires. That rim and tire combo, with her weight, allows her to easily run 90 psi safely, probably less if we wanted. Plus she isn't the most proficient at tire changes, although she can and has done it before, so that time and pressure should have given her a little extra margin.

I don't have a picture, but this link shows what it looks like. It is 2011 model, but the cable routing is very close to the same on my wife's bike:

http://cycnut.com/...5c-front-derailleur/

I'll look at it again tonight. Maybe I missed something.

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"...the street finds its own uses for things"

At 110, she should probably around 90psi with 23c tires.

I was using Sram Red front derailleur with 52t chainring and it worked great. I'm looking at the shimano ultegra and 105 and they seem to have the cable join the derailleur kind of high up which would in theory cause the cable to come back toward the tire. The Cable will join FD clamp slightly lower which will bring the cable forward when tension comes on. Notice in my picture that the cable has joined the derailleur and lined up to be between the two water bottle cage screws. Then look at the shimano 105 on the womens version. It joins slightly higher, lining up with the top water bottle cage screw and comes back toward the tire. Not sure if this is 100% the problem but this is where I would start making adjustments

Agreed, I'm also a small-ish woman and I run my 23c tires at around 90 (mind you I'm on 650c wheels). How is it that your wife has trouble pumping up her tires? With a good floor pump it's pretty easy to get at least 100 or so in there?

I pumped tires no problem at 106 lbs (me) to 120 psi.
The secret is to get a good floor pump with sturdy base. One that allows her to place her feet on the supports either side of the pump (for stabilizing the pump) Get her upper body weight directly over the pump and push. technique is everything!