Tire advice needed

[bskaje]

I bought a Trek Lexa SL at the end of last year and like it so far, but I'm pretty sensitive to road vibration. I've switched the saddle, wear cycling shorts and gloves, but I still feel it quite a bit. Now my riding distance is expanding and I'm finding riding on well-maintained crushed limestone (gravel) trails is going to be unavoidable at least part of the time. Also, I live in Wisconsin, which means we have some crappy roads due to freeze/thaw as well as sealcoat often used on roads for patching (though my concern is mostly with trails). Anyhow, I'm thinking of replacing my 700c x 23 tires with either 25's or 28's. I want more comfort and better handling on those trails (admittedly I haven't ridden the trails on my 23's much), but I also started to do triathlons and road races and am beginning to be somewhat competitive so I'm worried about how much speed/efficiency I'll sacrifice. Finally, I'm quite petite - 5'1" and 105 lbs, and I have an impossible time pumping my current tires up to 110 psi using my floor pump - I have to have my husband do it for me (not very practical). Any advice on 25's vs. 28's? Also, should I look at any tires specifically or just pick up the Bontragers at the Trek store? Would it be a stupid hassle to switch out 28's for training and 23's for events? Thanks for any advice!

[Sky King]

Riding a wider tire will definitely improve the ride however not sure your fork will accommodate a wider tire. A quick call to the LBS will answer that question. If so then also consider two sets of wheels so you can quickly switch out depending on what it is you want to do with the bike. For full disclosure I think a 28 tire is "narrow" as I ride a touring bike with a 650B wheel and about 40 mm wide tires.

[bskaje]

I did stop into the LBS yesterday and they said the bike can accommodate up to 28. I guess I just don't know if going up to 28's will sacrifice too much performance?

[Sky King]

Where's Mimi Some great articles about width and performance out there. Not sure how geeked out you want to get but here is just one of many articles in Bicycle Quarterly
In racing, a skinnier tire will come off the line faster, however, once up to speed a wider tire has no less performance and will roll just as fast. I am not a racer but have often caught up with a pack of roadie's and been able to ride with them on our local "bikeway" on my touring bike with my 650b x 40's. Going from a 23 to a 28 isn't going to drop your performance and hopefully will make your ride way more fun as you won't be bounced all over the place.

[indysteel]

In addition to a wider tire, I would also try lowering your PSI. At your weight, 110 psi, even for a 23cc tire, is arguably too high. There are some past threads on that issue if you'd like to read more about it.

As for changing out tires before a race, it's really not that big of a job, and it's a skill you need to know anyway. Think of it as good practice.

[Grits]

I don't race, but I ride with some racers and tri-people, and I know they would not want to give up speed when coming off the line. Two sets of wheels might be the answer. I wouldn't want to change tires for different events, although I guess you would get really good at it!

And +1 for Indysteels advice on PSI. At your weight, you probably don't need 110 PSI. In fact, riding a lower PSI would make your ride more comfortable.